Enable motor pins only for classic esp32 by default

Also simplify flix2 config code.
Docs fix
2026-08-16 00:38:56 +00:00 · 2026-08-16 01:26:34 +03:00 · 2026-08-16 00:10:19 +03:00 · 2026-08-14 09:41:35 +03:00 · 2026-08-14 06:18:17 +03:00 · 2026-08-14 06:11:43 +03:00
69 changed files with 1722 additions and 472 deletions
@@ -10,28 +10,38 @@ on:
 jobs:
  build_linux:
    runs-on: ubuntu-latest
+    env:
+        ARDUINO_SKETCH_ALWAYS_EXPORT_BINARIES: 1
    steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v7
    - name: Install Arduino CLI
      run: curl -fsSL https://raw.githubusercontent.com/arduino/arduino-cli/master/install.sh | BINDIR=/usr/local/bin sh
-    - name: Build firmware
-      env:
-        ARDUINO_SKETCH_ALWAYS_EXPORT_BINARIES: 1
+    - name: Build firmware for ESP32
      run: make
+    - name: Build firmware for ESP32-C3
+      run: make BOARD=esp32:esp32:esp32c3
+    - name: Build firmware for ESP32-S3
+      run: make BOARD=esp32:esp32:esp32s3:CDCOnBoot=cdc
+    - name: Build firmware for ESP32-S3 with QSPI PSRAM
+      run: make BOARD=esp32:esp32:esp32s3:CDCOnBoot=cdc,PSRAM=enabled EXTRA=--output-dir=flix/build/esp32.esp32.esp32s3.qspi
+    - name: Build firmware for ESP32-S3 with OPI PSRAM
+      run: make BOARD=esp32:esp32:esp32s3:CDCOnBoot=cdc,PSRAM=opi EXTRA=--output-dir=flix/build/esp32.esp32.esp32s3.opi
+    - name: Build firmware for Flix2
+      run: make BOARD=esp32:esp32:esp32s3:FlashSize=4M,CDCOnBoot=cdc,PSRAM=opi FLAGS=-DFLIX2 EXTRA=--output-dir=flix/build/esp32.esp32.flix2
    - name: Upload binaries
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v7
      with:
        name: firmware-binary
        path: flix/build
-    - name: Build firmware for ESP32-S3
-      run: make BOARD=esp32:esp32:esp32s3
+    - name: Build espnow-proxy
+      run: arduino-cli compile --fqbn esp32:esp32:esp32 tools/espnow-proxy
    - name: Check c_cpp_properties.json
      run: tools/check_c_cpp_properties.py

  build_macos:
    runs-on: macos-latest
    steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v7
    - name: Install Arduino CLI
      run: brew install arduino-cli
    - name: Build firmware
@@ -42,7 +52,7 @@ jobs:
  build_windows:
    runs-on: windows-latest
    steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v7
    - name: Install Arduino CLI
      run: choco install arduino-cli
    - name: Install Make
@@ -62,8 +72,8 @@ jobs:
        apt-get update
        DEBIAN_FRONTEND=noninteractive apt-get install -y curl wget build-essential cmake g++ pkg-config gnupg2 lsb-release sudo
    - name: Install Arduino CLI
-      uses: arduino/setup-arduino-cli@v1.1.1
-    - uses: actions/checkout@v4
+      run: curl -fsSL https://raw.githubusercontent.com/arduino/arduino-cli/master/install.sh | BINDIR=/usr/local/bin sh
+    - uses: actions/checkout@v7
    - name: Install Gazebo
      run: |
        sudo sh -c 'echo "deb http://packages.osrfoundation.org/gazebo/ubuntu-stable `lsb_release -cs` main" > /etc/apt/sources.list.d/gazebo-stable.list'
@@ -74,7 +84,16 @@ jobs:
      run: sudo apt-get install -y libsdl2-dev
    - name: Build simulator
      run: make build_simulator
-    - uses: actions/upload-artifact@v4
+    - name: Run simulator
+      env:
+        GAZEBO_MODEL_PATH: ${{ github.workspace }}/gazebo/models
+        GAZEBO_PLUGIN_PATH: ${{ github.workspace }}/gazebo/build
+      run: |
+        OUT=$(timeout -k 10s 120s gzserver --verbose gazebo/flix.world 2>&1 | tee /dev/stderr)
+        if echo "$OUT" | grep -Pq "\[Err\](?! \[RenderEngine)"; then
+          exit 1
+        fi
+    - uses: actions/upload-artifact@v7
      with:
        name: gazebo-plugin-binary
        path: gazebo/build/*.so
@@ -86,7 +105,7 @@ jobs:
    steps:
    - name: Install Arduino CLI
      run: brew install arduino-cli
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v7
    - name: Clean up python binaries # Workaround for https://github.com/actions/setup-python/issues/577
      run: |
        rm -f /usr/local/bin/2to3*
@@ -8,6 +8,7 @@ on:

 permissions:
  contents: read
+  actions: read
  pages: write
  id-token: write

@@ -15,7 +16,7 @@ jobs:
  markdownlint:
    runs-on: ubuntu-latest
    steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v7
    - name: Install markdownlint
      run: npm install -g markdownlint-cli2
    - name: Run markdownlint
@@ -24,19 +25,57 @@ jobs:
  build_book:
    runs-on: ubuntu-latest
    needs: markdownlint
+    env:
+      BINARIES: ${{ github.event_name == 'push' && (github.ref_name == 'master' || github.ref_name == 'dev') && github.repository == 'okalachev/flix' }}
    steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v7
    - name: Install mdBook
      run: cargo install mdbook --vers 0.4.43 --locked
    - name: Build book
      run: cd docs && mdbook build
+    - name: Wait for Build to complete
+      if: ${{ env.BINARIES }}
+      uses: lewagon/wait-on-check-action@v1.9.1
+      with:
+        ref: ${{ github.sha }}
+        check-name: build_linux
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
+        wait-interval: 30
+    - name: Find firmware binaries
+      if: ${{ env.BINARIES }}
+      id: build_run
+      run: |
+        RUN_ID=$(gh api "repos/${{ github.repository }}/actions/workflows/build.yml/runs?head_sha=${{ github.sha }}&per_page=1" --jq '.workflow_runs[0].id')
+        echo "id=$RUN_ID" >> $GITHUB_OUTPUT
+      env:
+        GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+    - name: Download firmware binaries
+      if: ${{ env.BINARIES }}
+      uses: actions/download-artifact@v7
+      with:
+        github-token: ${{ secrets.GITHUB_TOKEN }}
+        repository: ${{ github.repository }}
+        run-id: ${{ steps.build_run.outputs.id }}
+        name: firmware-binary
+        path: docs/build
+    - name: Create shortcuts for firmware binaries
+      if: ${{ env.BINARIES }}
+      working-directory: docs/build
+      run: |
+        for FQBN in esp32.esp32.*; do
+          zip -r $FQBN.zip $FQBN
+          BOARD="${FQBN#esp32.esp32.}"
+          ln -s "$FQBN/flix.ino.merged.bin" "flix.$BOARD.merged.bin"
+          ln -s "$FQBN/flix.ino.bin" "flix.$BOARD.bin"
+          ln -s "$FQBN/flix.ino.bootloader.bin" "flix.$BOARD.bootloader.bin"
+        done
    - name: Upload artifact
-      uses: actions/upload-pages-artifact@v3
+      uses: actions/upload-pages-artifact@v5
      with:
        path: docs/build

  deploy:
-    if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/master' }}
+    if: ${{ github.event_name == 'push' && github.ref_name == 'master' }}
    concurrency:
      group: "pages"
      cancel-in-progress: true
@@ -48,4 +87,4 @@ jobs:
    steps:
      - name: Deploy to GitHub Pages
        id: deployment
-        uses: actions/deploy-pages@v4
+        uses: actions/deploy-pages@v5
@@ -10,7 +10,7 @@ jobs:
  csv_to_ulog:
    runs-on: ubuntu-latest
    steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v7
    - name: Build csv_to_ulog
      run: cd tools/csv_to_ulog && mkdir build && cd build && cmake .. && make
    - name: Test csv_to_ulog
@@ -22,13 +22,13 @@ jobs:
  pyflix:
    runs-on: ubuntu-latest
    steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v7
    - name: Install Python build tools
      run: pip install build
    - name: Build pyflix
      run: python3 -m build tools
    - name: Upload artifacts
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v7
      with:
        name: pyflix
        path: |
@@ -37,7 +37,7 @@ jobs:
  python_tools:
    runs-on: ubuntu-latest
    steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v7
    - name: Install Python dependencies
      run: pip install -r tools/requirements.txt
    - name: Test csv_to_mcap tool
@@ -46,3 +46,23 @@ jobs:
        echo -e "t,x,y,z\n0,1,2,3\n1,4,5,6" > log.csv
        ./csv_to_mcap.py log.csv
        test $(stat -c %s log.mcap) -eq 883
+  sloc:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v7
+    - run: sudo apt-get install -y cloc jq
+    - name: Print source lines of code
+      run: cloc --by-file-by-lang flix
+    - name: Checkout previous revision
+      uses: actions/checkout@v7
+      with:
+        ref: ${{ github.event_name == 'pull_request' && github.event.pull_request.base.sha || github.event.before }}
+        path: prev
+    - name: Annotate total source lines
+      run: |
+        SLOC_CURR=$(cloc flix --json | jq -r '.SUM.code')
+        SLOC_PREV=$(cloc prev/flix --json | jq -r '.SUM.code')
+        DIFF=$(printf '%+d' "$((SLOC_CURR - SLOC_PREV))")
+        echo "* Current SLOC: $SLOC_CURR" >> $GITHUB_STEP_SUMMARY
+        echo "* Previous SLOC: $SLOC_PREV" >> $GITHUB_STEP_SUMMARY
+        echo "* Diff: $DIFF" >> $GITHUB_STEP_SUMMARY
@@ -4,9 +4,10 @@ build/
 tools/log/
 tools/dist/
 *.egg-info/
-.dependencies
+.core
+.libs
 .vscode/*
-!.vscode/settings.json
+!.vscode/settings.default.json
 !.vscode/c_cpp_properties.json
 !.vscode/tasks.json
 !.vscode/launch.json
@@ -6,18 +6,18 @@
 				"${workspaceFolder}/flix",
 				"${workspaceFolder}/gazebo",
 				"${workspaceFolder}/tools/**",
-				"~/.arduino15/packages/esp32/hardware/esp32/3.3.6/cores/esp32",
-				"~/.arduino15/packages/esp32/hardware/esp32/3.3.6/libraries/**",
-				"~/.arduino15/packages/esp32/hardware/esp32/3.3.6/variants/d1_mini32",
-				"~/.arduino15/packages/esp32/tools/esp32-libs/3.3.6/include/**",
+				"~/.arduino15/packages/esp32/hardware/esp32/3.3.10/cores/esp32",
+				"~/.arduino15/packages/esp32/hardware/esp32/3.3.10/libraries/**",
+				"~/.arduino15/packages/esp32/hardware/esp32/3.3.10/variants/d1_mini32",
+				"~/.arduino15/packages/esp32/tools/esp32-libs/3.3.10/include/**",
 				"~/Arduino/libraries/**",
 				"/usr/include/gazebo-11/",
 				"/usr/include/ignition/math6/"
 			],
 			"forcedInclude": [
 				"${workspaceFolder}/.vscode/intellisense.h",
-				"~/.arduino15/packages/esp32/hardware/esp32/3.3.6/cores/esp32/Arduino.h",
-				"~/.arduino15/packages/esp32/hardware/esp32/3.3.6/variants/d1_mini32/pins_arduino.h",
+				"~/.arduino15/packages/esp32/hardware/esp32/3.3.10/cores/esp32/Arduino.h",
+				"~/.arduino15/packages/esp32/hardware/esp32/3.3.10/variants/d1_mini32/pins_arduino.h",
 				"${workspaceFolder}/flix/cli.ino",
 				"${workspaceFolder}/flix/control.ino",
 				"${workspaceFolder}/flix/estimate.ino",
@@ -33,7 +33,7 @@
 				"${workspaceFolder}/flix/parameters.ino",
 				"${workspaceFolder}/flix/safety.ino"
 			],
-			"compilerPath": "~/.arduino15/packages/esp32/tools/esp-x32/2511/bin/xtensa-esp32-elf-g++",
+			"compilerPath": "~/.arduino15/packages/esp32/tools/esp-x32/2601/bin/xtensa-esp32-elf-g++",
 			"cStandard": "c11",
 			"cppStandard": "c++17",
 			"defines": [
@@ -53,18 +53,18 @@
 			"name": "Mac",
 			"includePath": [
 				"${workspaceFolder}/flix",
-				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.3.6/cores/esp32",
-				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.3.6/libraries/**",
-				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.3.6/variants/d1_mini32",
-				"~/Library/Arduino15/packages/esp32/tools/esp32-libs/3.3.6/include/**",
+				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.3.10/cores/esp32",
+				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.3.10/libraries/**",
+				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.3.10/variants/d1_mini32",
+				"~/Library/Arduino15/packages/esp32/tools/esp32-libs/3.3.10/include/**",
 				"~/Documents/Arduino/libraries/**",
 				"/opt/homebrew/include/gazebo-11/",
 				"/opt/homebrew/include/ignition/math6/"
 			],
 			"forcedInclude": [
 				"${workspaceFolder}/.vscode/intellisense.h",
-				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.3.6/cores/esp32/Arduino.h",
-				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.3.6/variants/d1_mini32/pins_arduino.h",
+				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.3.10/cores/esp32/Arduino.h",
+				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.3.10/variants/d1_mini32/pins_arduino.h",
 				"${workspaceFolder}/flix/flix.ino",
 				"${workspaceFolder}/flix/cli.ino",
 				"${workspaceFolder}/flix/control.ino",
@@ -80,7 +80,7 @@
 				"${workspaceFolder}/flix/parameters.ino",
 				"${workspaceFolder}/flix/safety.ino"
 			],
-			"compilerPath": "~/Library/Arduino15/packages/esp32/tools/esp-x32/2511/bin/xtensa-esp32-elf-g++",
+			"compilerPath": "~/Library/Arduino15/packages/esp32/tools/esp-x32/2601/bin/xtensa-esp32-elf-g++",
 			"cStandard": "c11",
 			"cppStandard": "c++17",
 			"defines": [
@@ -103,16 +103,16 @@
 				"${workspaceFolder}/flix",
 				"${workspaceFolder}/gazebo",
 				"${workspaceFolder}/tools/**",
-				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.3.6/cores/esp32",
-				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.3.6/libraries/**",
-				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.3.6/variants/d1_mini32",
-				"~/AppData/Local/Arduino15/packages/esp32/tools/esp32-libs/3.3.6/include/**",
+				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.3.10/cores/esp32",
+				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.3.10/libraries/**",
+				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.3.10/variants/d1_mini32",
+				"~/AppData/Local/Arduino15/packages/esp32/tools/esp32-libs/3.3.10/include/**",
 				"~/Documents/Arduino/libraries/**"
 			],
 			"forcedInclude": [
 				"${workspaceFolder}/.vscode/intellisense.h",
-				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.3.6/cores/esp32/Arduino.h",
-				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.3.6/variants/d1_mini32/pins_arduino.h",
+				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.3.10/cores/esp32/Arduino.h",
+				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.3.10/variants/d1_mini32/pins_arduino.h",
 				"${workspaceFolder}/flix/cli.ino",
 				"${workspaceFolder}/flix/control.ino",
 				"${workspaceFolder}/flix/estimate.ino",
@@ -128,7 +128,7 @@
 				"${workspaceFolder}/flix/parameters.ino",
 				"${workspaceFolder}/flix/safety.ino"
 			],
-			"compilerPath": "~/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2511/bin/xtensa-esp32-elf-g++.exe",
+			"compilerPath": "~/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2601/bin/xtensa-esp32-elf-g++.exe",
 			"cStandard": "c11",
 			"cppStandard": "c++17",
 			"defines": [
@@ -1,6 +1,7 @@
 {
 	// See https://go.microsoft.com/fwlink/?LinkId=827846 to learn about workspace recommendations.
 	"recommendations": [
+		"dangmai.workspace-default-settings",
 		"ms-vscode.cpptools",
 		"ms-vscode.cmake-tools",
 		"ms-python.python"
@@ -1,29 +1,44 @@
-BOARD = esp32:esp32:d1_mini32
-PORT := $(wildcard /dev/serial/by-id/usb-Silicon_Labs_CP21* /dev/serial/by-id/usb-1a86_USB_Single_Serial_* /dev/cu.usbserial-*)
-PORT := $(strip $(PORT))
+BOARD = esp32:esp32:esp32
+PORT := $(strip $(wildcard /dev/serial/by-id/usb-Silicon_Labs_CP21* /dev/serial/by-id/usb-1a86_USB_Single_Serial_* /dev/cu.usbserial-* /dev/cu.usbmodem*))
+VERSION = $(shell git describe --always --dirty)

-build: .dependencies
-	arduino-cli compile --fqbn $(BOARD) flix
+export ARDUINO_NETWORK_CONNECTION_TIMEOUT := 1h
+
+build: .core .libs
+	arduino-cli compile flix \
+		--fqbn $(BOARD) \
+		--build-property "build.core_debug_level=1" \
+		--build-property "compiler.cpp.extra_flags=-DVERSION=$(VERSION) $(FLAGS)" $(EXTRA)

 upload: build
-	arduino-cli upload --fqbn $(BOARD) -p "$(PORT)" flix
+	arduino-cli upload flix --fqbn $(BOARD) -p "$(PORT)"
+
+erase:
+	arduino-cli burn-bootloader --fqbn $(BOARD) -p "$(PORT)" -P esptool

 monitor:
 	arduino-cli monitor -p "$(PORT)" -c baudrate=115200

-dependencies .dependencies:
-	arduino-cli core update-index --config-file arduino-cli.yaml
-	arduino-cli core install esp32:esp32@3.3.6 --config-file arduino-cli.yaml
+core .core:
+	arduino-cli core update-index --additional-urls https://espressif.github.io/arduino-esp32/package_esp32_index.json
+	arduino-cli core install esp32:esp32@3.3.10 --additional-urls https://espressif.github.io/arduino-esp32/package_esp32_index.json
+	touch .core
+
+libs .libs:
 	arduino-cli lib update-index
-	arduino-cli lib install "FlixPeriph"
+	ARDUINO_LIBRARY_ENABLE_UNSAFE_INSTALL=1 arduino-cli lib install --git-url 'https://github.com/okalachev/flixperiph.git#dev'
 	arduino-cli lib install "MAVLink"@2.0.25
-	touch .dependencies
+	touch .libs
+
+upload_proxy: .core .libs
+	arduino-cli compile tools/espnow-proxy --fqbn $(BOARD)
+	arduino-cli upload tools/espnow-proxy --fqbn $(BOARD) -p "$(PORT)"

 gazebo/build cmake: gazebo/CMakeLists.txt
 	mkdir -p gazebo/build
 	cd gazebo/build && cmake ..

-build_simulator: .dependencies gazebo/build
+build_simulator: .libs gazebo/build
 	make -C gazebo/build

 simulator: build_simulator
@@ -38,6 +53,6 @@ plot:
 	plotjuggler -d $(shell ls -t tools/log/*.csv | head -n1)

 clean:
-	rm -rf gazebo/build flix/build flix/cache .dependencies
+	rm -rf gazebo/build flix/build flix/cache .core .libs

-.PHONY: build upload monitor dependencies cmake build_simulator simulator log clean
+.PHONY: build upload monitor core libs cmake build_simulator simulator log clean
@@ -21,8 +21,8 @@
 * Dedicated for education and research.
 * Made from general-purpose components.
 * Simple and clean source code in Arduino (<2k lines firmware).
-* Connectivity using Wi-Fi and MAVLink protocol.
-* Control using USB gamepad, remote control or smartphone.
+* Communication using MAVLink protocol over Wi-Fi or ESP-NOW.
+* Control with USB gamepad, remote control or smartphone.
 * Wireless command line interface and analyzing.
 * Precise simulation with Gazebo.
 * Python library for scripting and automatic flights.
@@ -47,13 +47,27 @@ See the [user builds gallery](docs/user.md):

 <a href="docs/user.md"><img src="docs/img/user/user.jpg" width=500></a>

+### PCB
+
+The official PCB *(Flix2)* is in development now. Follow the [project's channel](https://t.me/opensourcequadcopter) to track the progress.
+
+Outdoor flights demo video of the current prototype:
+
+<a href="https://youtu.be/KXlNmvUTi4g"><img width=300 src="https://i3.ytimg.com/vi/KXlNmvUTi4g/maxresdefault.jpg"></a>
+
+### Position control
+
+The position control feature is in development. RoboCamp 2026 demo (using an overhead camera, [sources](https://github.com/xTimop/flix-poscontrol/compare/robolager2026...xTimop:flix-poscontrol:poscontrol)):
+
+<a href="https://youtu.be/369Xowm4HcU"><img width=300 src="https://i3.ytimg.com/vi/369Xowm4HcU/maxresdefault.jpg"></a>
+
 ## Simulation

 The simulator is implemented using Gazebo and runs the original Arduino code:

 <img src="docs/img/simulator1.png" width=500 alt="Flix simulator">

-## Documentation
+## Documentation articles

 1. [Assembly instructions](docs/assembly.md).
 2. [Usage: build, setup and flight](docs/usage.md).
@@ -71,14 +85,14 @@ Additional articles:

 |Type|Part|Image|Quantity|
 |-|-|:-:|:-:|
-|Microcontroller board|ESP32 Mini|<img src="docs/img/esp32.jpg" width=100>|1|
-|IMU (and barometer¹) board|GY‑91, MPU-9265 (or other MPU‑9250/MPU‑6500 board)<br>ICM20948V2 (ICM‑20948)³<br>GY-521 (MPU-6050)³⁻¹|<img src="docs/img/gy-91.jpg" width=90 align=center><br><img src="docs/img/icm-20948.jpg" width=100><br><img src="docs/img/gy-521.jpg" width=100>|1|
-|Boost converter (optional, for more stable power supply)|5V output|<img src="docs/img/buck-boost.jpg" width=100>|1|
+|Microcontroller board|ESP32 Mini.<br>ESP32-S3/ESP32-C3 boards are also supported.|<img src="docs/img/esp32.jpg" width=100>|1|
+|IMU (and barometer¹) board|GY‑91, MPU-9265 (or other MPU‑9250/MPU‑6500 board)<br>ICM20948V2 (ICM‑20948)<br>GY-521 (MPU-6050)|<img src="docs/img/gy-91.jpg" width=90 align=center><br><img src="docs/img/icm-20948.jpg" width=100><br><img src="docs/img/gy-521.jpg" width=100>|1|
+|*Boost converter (optional, for more stable power supply)*|*5V output*|<img src="docs/img/buck-boost.jpg" width=100>|1|
 |Motor|8520 3.7V brushed motor.<br>Motor with exact 3.7V voltage is needed, not ranged working voltage (3.7V — 6V).<br>Make sure the motor shaft diameter and propeller hole diameter match!|<img src="docs/img/motor.jpeg" width=100>|4|
-|Propeller|55 mm (alternatively 65 mm)|<img src="docs/img/prop.jpg" width=100>|4|
-|MOSFET (transistor)|100N03A or [analog](https://t.me/opensourcequadcopter/33)|<img src="docs/img/100n03a.jpg" width=100>|4|
-|Pull-down resistor|10 kΩ|<img src="docs/img/resistor10k.jpg" width=100>|4|
-|3.7V Li-Po battery|LW 952540 (or any compatible by the size)|<img src="docs/img/battery.jpg" width=100>|1|
+|Propeller|55 mm or 65 mm|<img src="docs/img/prop.jpg" width=100>|4|
+|MOSFET (transistor)|UMW 100N03A or [analog](https://t.me/opensourcequadcopter/33).<br>Warning: don't use KIA 100N03A or other manufacturers, they might not work!|<img src="docs/img/100n03a.jpg" width=100>|4|
+|Pull-down resistor<br>Voltage measurement resistor|10 kΩ|<img src="docs/img/resistor10k.jpg" width=100>|6|
+|3.7V Li-Po battery|LW 952540 (or any compatible by the size).<br>Make sure the battery has enough discharge rate — 25C or more!|<img src="docs/img/battery.jpg" width=100>|1|
 |Battery connector cable|MX2.0 2P female|<img src="docs/img/mx.png" width=100>|1|
 |Li-Po Battery charger|Any|<img src="docs/img/charger.jpg" width=100>|1|
 |Screws for IMU board mounting|M3x5|<img src="docs/img/screw-m3.jpg" width=100>|2|
@@ -152,14 +166,16 @@ You can see a user-contributed [variant of complete circuit diagram](https://mir
  |-|-|
  |GND|GND|
  |VIN|VCC (or 3.3V depending on the receiver)|
-  |Signal (TX)|GPIO4¹|
+  |Signal (TX)|GPIO4|

-*¹ — UART2 RX pin was [changed](https://docs.espressif.com/projects/arduino-esp32/en/latest/migration_guides/2.x_to_3.0.html#id14) to GPIO4 in Arduino ESP32 core 3.0.*
+* Optionally connect the battery voltage divider for voltage monitoring to any ADC1 pin (e. g. *GPIO32* on ESP32, *GPIO3* on ESP32-S3).
+
+  ESP32 and ESP32-S3 [can measure](https://docs.espressif.com/projects/arduino-esp32/en/latest/api/adc.html#analogsetattenuation) up to 3.1 V and ESP32-S3/ESP32-C3 can measure up to 2.5 V, so choose the voltage divider resistors accordingly.

 ## Resources

 * Telegram channel on developing the drone and the flight controller (in Russian): https://t.me/opensourcequadcopter.
-* Official Telegram chat: https://t.me/opensourcequadcopterchat.
+* Official Telegram chat: https://t.me/opensourcequadcopterchat (English / Russian).
 * Detailed article on Habr.com about the development of the drone (in Russian): https://habr.com/ru/articles/814127/.

 ## Disclaimer
@@ -1,5 +0,0 @@
-board_manager:
-  additional_urls:
-    - https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json
-network:
-  connection_timeout: 1h
@@ -28,6 +28,8 @@ Soldered components ([schematics variant](https://miro.com/app/board/uXjVN-dTjoo

 <img src="img/assembly/7.jpg" width=600>

+See an alternative assembly process photos here: https://drive.google.com/drive/folders/1FG5BH9RCzdf1XmJcC70PymiRMXcz6Fx7?usp=sharing.
+
 ## Motor directions

 > [!WARNING]
@@ -31,7 +31,7 @@

 * [`vector.h`](https://github.com/okalachev/flix/blob/master/flix/vector.h), [`quaternion.h`](https://github.com/okalachev/flix/blob/master/flix/quaternion.h) — библиотеки векторов и кватернионов.
 * [`pid.h`](https://github.com/okalachev/flix/blob/master/flix/pid.h) — ПИД-регулятор.
-* [`lpf.h`](https://github.com/okalachev/flix/blob/master/flix/lpf.h) — фильтр нижних частот.
+* [`filter.h`](https://github.com/okalachev/flix/blob/master/flix/filter.h) — фильтр нижних частот.

 ### Подсистема управления

@@ -34,7 +34,7 @@ Utility files:

 * [`vector.h`](../flix/vector.h), [`quaternion.h`](../flix/quaternion.h) — vector and quaternion libraries.
 * [`pid.h`](../flix/pid.h) — generic PID controller.
-* [`lpf.h`](../flix/lpf.h) — generic low-pass filter.
+* [`filter.h`](../flix/filter.h) — generic low-pass filter.

 ### Control subsystem

@@ -67,6 +67,38 @@ In order to add a console command, modify the `doCommand()` function in `cli.ino
 >
 > For on-the-ground commands, use `pause()` function, instead of `delay()`. This function allows to pause in a way that MAVLink connection will continue working.

+### Parameter subsystem
+
+Parameters subsystem (`parameters.ino`) uses standard [Preferences.h](https://docs.espressif.com/projects/arduino-esp32/en/latest/tutorials/preferences.html) ESP32 library to store parameters in non-volatile memory. Each parameter is a regular global variable, which is registered in the `parameters` array.
+
+To add a new parameter:
+
+1. Define a global variable for the parameter, three types are supported: `float`, `int`, and `bool`.
+2. Add an entry to the `parameters` array, with the parameter name, a pointer to the variable, and optionally a callback function to call when the parameter is changed.
+3. Everything else will be handled automatically.
+
+See examples of adding new parameters in commits: [c434107](https://github.com/okalachev/flix/commit/c434107), [a687303](https://github.com/okalachev/flix/commit/a687303).
+
+> [!NOTE]
+> Since all the parameters are internally stored and passed as floats, the safe range for `int` parameters is -16777216 to 16777215.
+
+## Adding a subsystem
+
+To add a new subsystem:
+
+1. Create a new `*.ino` file for your subsystem.
+2. Define setup and loop functions for the subsystem, for example `setupMySubsystem()` and `loopMySubsystem()`.
+3. Use `Rate` class if you need to limit the loop frequency, for example:
+
+    ```cpp
+    Rate mySubsystemRate(100); // 100 Hz
+
+    void loopMySubsystem() {
+    	if (!mySubsystemRate) return;
+    	// Do something...
+    }
+4. Add setup and loop calls in to `setup()` and `loop()` functions in `flix.ino`.
+
 ## Building the firmware

 See build instructions in [usage.md](usage.md).
@@ -5,27 +5,32 @@
 Do the following:

 * **Check ESP32 core is installed**. Check if the version matches the one used in the [tutorial](usage.md#building-the-firmware).
-* **Check libraries**. Install all the required libraries from the tutorial. Make sure there are no MPU9250 or other peripherals libraries that may conflict with the ones used in the tutorial.
+* **Check libraries**. Install all the required libraries from the tutorial. Make sure there are no MPU-9250 or other peripherals libraries that may conflict with the ones used in the tutorial.
 * **Check the chosen board**. The correct board to choose in Arduino IDE for ESP32 Mini is *WEMOS D1 MINI ESP32*.

 ## The drone doesn't fly

 Do the following:

-* **Check the battery voltage**. Use a multimeter to measure the battery voltage. It should be in range of 3.7-4.2 V.
+* **Check the battery voltage**. Use a multimeter to measure the battery voltage. The fully charged battery should have about 4.2V.
+* **Check the battery you use has enough discharge current**. The battery should be able to provide 15A of current. So the C-rating for a 1000 mAh battery should be at least 15C (higher is better).
 * **Check if there are some startup errors**. Connect the ESP32 to the computer and check the Serial Monitor output. Use the Reset button or `reboot` command to see the whole startup output.
 * **Check the baudrate is correct**. If you see garbage characters in the Serial Monitor, make sure the baudrate is set to 115200.
-* **Make sure correct IMU model is chosen**. If using ICM-20948/MPU-6050 board, change `MPU9250` to `ICM20948`/`MPU6050` in the `imu.ino` file.
 * **Check if the console is working**. Perform `help` command in Serial Monitor. You should see the list of available commands. You can also access the console using QGroundControl *(Vehicle Setup* ⇒ *Analyze Tools* ⇒ *MAVLink Console)*.
 * **Configure QGroundControl correctly before connecting to the drone** if you use it to control the drone. Go to the settings and enable *Virtual Joystick*. *Auto-Center Throttle* setting **should be disabled**.
 * **If QGroundControl doesn't connect**, you might need to disable the firewall and/or VPN on your computer.
+* **Make sure correct IMU model is chosen**. If using ICM-20948/MPU-6050 board, change `MPU9250` to `ICM20948`/`MPU6050` in the `imu.ino` file.
 * **Check the IMU is working**. Perform `imu` command and check its output:
  * The `status` field should be `OK`.
  * The `rate` field should be about 1000 (Hz).
  * The `accel` and `gyro` fields should change as you move the drone.
-* **Calibrate the accelerometer.** if is wasn't done before. Type `ca` command in Serial Monitor and follow the instructions.
-* **Check the attitude estimation**. Connect to the drone using QGroundControl. Rotate the drone in different orientations and check if the attitude estimation shown in QGroundControl is correct.
 * **Check the IMU orientation is set correctly**. If the attitude estimation is rotated, set the correct IMU orientation as described in the [tutorial](usage.md#define-imu-orientation).
+* **Calibrate the accelerometer.** if is wasn't done before. Type `ca` command in Serial Monitor and follow the instructions.
+* **Check the attitude estimation**. Connect to the drone using QGroundControl. Rotate the drone in different orientations and check if the attitude estimation is shown exactly as on the video below:
+
+  <a href="https://youtu.be/yVRN23-GISU"><img width=200 src="https://i3.ytimg.com/vi/yVRN23-GISU/maxresdefault.jpg"></a>
+
+* **Check the IMU output**. Connect to the drone using QGroundControl on your computer. Go to the *Analyze* tab, *MAVLINK Inspector*. Plot the data from the `SCALED_IMU` message. The gyroscope and accelerometer data should change according to the drone movement.
 * **Check the motors type**. Motors with exact 3.7V voltage are needed, not ranged working voltage (3.7V — 6V).
 * **Check the motors**. Perform the following commands using Serial Monitor:
  * `mfr` — should rotate front right motor (counter-clockwise).
@@ -33,9 +38,10 @@ Do the following:
  * `mrl` — should rotate rear left motor (counter-clockwise).
  * `mrr` — should rotate rear right motor (clockwise).
 * **Check the propeller directions are correct**. Make sure your propeller types (A or B) are installed as on the picture:
+
  <img src="img/user/peter_ukhov-2/1.jpg" width="200">
-* **Check the remote control**. Using `rc` command, check the control values reflect your sticks movement. All the controls should change between -1 and 1, and throttle between 0 and 1.
-* **If using SBUS receiver**:
+
+* **If using an SBUS receiver**:
  * **Define the used GPIO pin** in `RC_RX_PIN` parameter.
  * **Calibrate the RC** using `cr` command in the console.
-* **Check the IMU output using QGroundControl**. Connect to the drone using QGroundControl on your computer. Go to the *Analyze* tab, *MAVLINK Inspector*. Plot the data from the `SCALED_IMU` message. The gyroscope and accelerometer data should change according to the drone movement.
+  * **Check the controls** using `rc` command. All the controls should change between -1 and 1, and the throttle between 0 and 1.
@@ -1,34 +1,63 @@
 # Usage: build, setup and flight

-To fly Flix quadcopter, you need to build the firmware, upload it to the ESP32 board, and set up the drone for flight.
+To fly Flix quadcopter, you need to upload the firmware to the ESP32 board, and set up the drone for flight.

-To get the firmware sources, clone the repository using git:
+## Uploading the firmware
+
+You can either use the **prebuilt binaries** or **build the firmware** from sources — this will let you modify the firmware and add new features.
+
+### Prebuilt binaries (the easiest way)
+
+1. Download the latest firmware file using the following links:
+
+   <!-- markdownlint-disable MD044 -->
+   |Type|Boards|Link|
+   |-|-|-|
+   |ESP32|DevKit, D1 Mini|[`quadcopter.dev/flix.esp32.merged.bin`](https://quadcopter.dev/flix.esp32.merged.bin)|
+   |ESP32-S3|Most S3 based|[`quadcopter.dev/flix.esp32s3.merged.bin`](https://quadcopter.dev/flix.esp32s3.merged.bin)|
+   |ESP32-S3 (2MB PSRAM)|S3 Super Mini, S3 Zero (2MB PSRAM)|[`quadcopter.dev/flix.esp32s3.qspi.merged.bin`](https://quadcopter.dev/flix.esp32s3.qspi.merged.bin)|
+   |ESP32-S3 (8/16MB PSRAM)|S3 Zero (8MB PSRAM)|[`quadcopter.dev/flix.esp32s3.opi.merged.bin`](https://quadcopter.dev/flix.esp32s3.opi.merged.bin)|
+   |ESP32-C3|C3 Super Mini|[`quadcopter.dev/flix.esp32c3.merged.bin`](https://quadcopter.dev/flix.esp32c3.merged.bin)|
+   |Flix2|Flix2 board|[`quadcopter.dev/flix.flix2.merged.bin`](https://quadcopter.dev/flix.flix2.merged.bin)|
+   <!-- markdownlint-enable MD044 -->
+
+2. Flash your ESP32 board using [ESP32 Web Flasher](https://www.espboards.dev/tools/program/):
+
+   <img src="img/web-flasher.png" width="400">
+
+   * Connect the board to your computer, press *Connect to ESP*, choose the serial port.
+   * Go to the *Flash* tab.
+   * Choose the downloaded firmware file, set *Flash address* to *0* (important).
+   * Click *Program* button and wait until the process is finished.
+
+### Building from sources (flexible)
+
+You can build and upload the firmware using either **Arduino IDE** (easier for beginners) or **command line**.
+
+Get the sources using git:

 ```bash
 git clone https://github.com/okalachev/flix.git && cd flix
 ```

-Beginners can [download the source code as a ZIP archive](https://github.com/okalachev/flix/archive/refs/heads/master.zip).
+Beginners can [download the sources as a ZIP archive](https://github.com/okalachev/flix/archive/refs/heads/master.zip).

-## Building the firmware
-
-You can build and upload the firmware using either **Arduino IDE** (easier for beginners) or **command line**.
-
-### Arduino IDE (Windows, Linux, macOS)
+#### Arduino IDE (Windows, Linux, macOS)

 <img src="img/arduino-ide.png" width="400" alt="Flix firmware open in Arduino IDE">

 1. Install [Arduino IDE](https://www.arduino.cc/en/software) (version 2 is recommended).
 2. *Windows users might need to install [USB to UART bridge driver from Silicon Labs](https://www.silabs.com/developers/usb-to-uart-bridge-vcp-drivers).*
-3. Install ESP32 core, version 3.3.6. See the [official Espressif's instructions](https://docs.espressif.com/projects/arduino-esp32/en/latest/installing.html#installing-using-arduino-ide) on installing ESP32 Core in Arduino IDE.
+3. Install ESP32 core, version 3.3.10. See the [official Espressif's instructions](https://docs.espressif.com/projects/arduino-esp32/en/latest/installing.html#installing-using-arduino-ide) on installing ESP32 Core in Arduino IDE.
 4. Install the following libraries using [Library Manager](https://docs.arduino.cc/software/ide-v2/tutorials/ide-v2-installing-a-library):
   * `FlixPeriph`, the latest version.
   * `MAVLink`, version 2.0.25.
 5. Open the `flix/flix.ino` sketch from downloaded firmware sources in Arduino IDE.
-6. Connect your ESP32 board to the computer and choose correct board type in Arduino IDE (*WEMOS D1 MINI ESP32* for ESP32 Mini) and the port.
-7. [Build and upload](https://docs.arduino.cc/software/ide-v2/tutorials/getting-started/ide-v2-uploading-a-sketch) the firmware using Arduino IDE.
+6. Connect your ESP32 board to the computer and choose correct board type in Arduino IDE (*WEMOS D1 MINI ESP32* for ESP32 Mini, *ESP32S3 Dev Module* for ESP32-S3 Super Mini) and the port.
+7. Set *Tools* ⇒ *Core Debug Level* to *Error* to see the errors in the serial console. Set *Tools* ⇒ *USB CDC on Boot* to *Enabled* for ESP32-S3/ESP32-C3 boards.
+8. [Build and upload](https://docs.arduino.cc/software/ide-v2/tutorials/getting-started/ide-v2-uploading-a-sketch) the firmware using Arduino IDE.

-### Command line (Windows, Linux, macOS)
+#### Command line (Windows, Linux, macOS)

 1. [Install Arduino CLI](https://arduino.github.io/arduino-cli/installation/).

@@ -57,6 +86,12 @@ You can build and upload the firmware using either **Arduino IDE** (easier for b
   make upload monitor
   ```

+   For ESP32-S3/ESP32-C3 boards, set the appropriate [FQBN](https://docs.arduino.cc/arduino-cli/FAQ/#whats-the-fqbn-string) using `BOARD` parameter:
+
+   ```bash
+   make BOARD=esp32:esp32:esp32s3:FlashSize=4M,CDCOnBoot=cdc upload
+   ```
+
 See other available Make commands in [Makefile](../Makefile).

 > [!TIP]
@@ -64,15 +99,6 @@ See other available Make commands in [Makefile](../Makefile).

 ## Before first flight

-### Choose the IMU model
-
-In case if using different IMU model than MPU9250, change `imu` variable declaration in the `imu.ino`:
-
-```cpp
-ICM20948 imu(SPI);  // For ICM-20948
-MPU6050 imu(Wire);  // For MPU-6050
-```
-
 ### Connect using QGroundControl

 QGroundControl is a ground control station software that can be used to monitor and control the drone.
@@ -82,6 +108,9 @@ QGroundControl is a ground control station software that can be used to monitor
 3. Connect your computer or smartphone to the appeared `flix` Wi-Fi network (password: `flixwifi`).
 4. Launch QGroundControl app. It should connect and begin showing the drone's telemetry automatically.

+> [!TIP]
+> If QGroundControl doesn't connect, try to disable the firewall and/or VPN on your computer, as they may block the connection.
+
 ### Access console

 The console is a command line interface (CLI) that allows to interact with the drone, change parameters, and perform various actions. There are two ways of accessing the console: using **serial port** or using **QGroundControl (wirelessly)**.
@@ -95,7 +124,7 @@ To access the console using serial port:
 To access the console using QGroundControl:

 1. Connect to the drone using QGroundControl app.
-2. Go to the QGroundControl menu ⇒ *Vehicle Setup* ⇒ *Analyze Tools* ⇒ *MAVLink Console*.
+2. Go to the QGroundControl menu ⇒ *Analyze Tools* ⇒ *MAVLink Console*.

 <img src="img/cli.png" width="400">

@@ -110,11 +139,22 @@ The drone is configured using parameters. To access and modify them, go to the Q

 You can also work with parameters using `p` command in the console. Parameter names are case-insensitive.

+### Configure the IMU
+
+1. Configure the following parameters for the IMU:
+   * `IMU_MODEL` — IMU model (1 for MPU-9250/MPU-6500, 2 for ICM-20948, 3 for MPU-6050, 4 for ICM-40609-D).
+   * `IMU_BUS` — communication bus (0 for SPI, 1 for I²C).
+   * `IMU_PIN_SCK`, `IMU_PIN_MISO`, `IMU_PIN_MOSI`, `IMU_PIN_CS` — SPI pin numbers.
+   * `IMU_PIN_SCL`, `IMU_PIN_SDA` — I²C pin numbers.
+   * `IMU_PIN_INT` — IMU data ready pin number (-1 if not used).
+2. Reboot the drone.
+3. Check the IMU is working using `imu` command in the console (should print `status: OK`).
+
 ### Define IMU orientation

-Use parameters, to define the IMU board axes orientation relative to the drone's axes: `IMU_ROT_ROLL`, `IMU_ROT_PITCH`, and `IMU_ROT_YAW`.
+The IMU orientation (relative to the drone's axes) is defined using the parameters: `IMU_ROT_ROLL`, `IMU_ROT_PITCH`, and `IMU_ROT_YAW`.

-The drone has *X* axis pointing forward, *Y* axis pointing left, and *Z* axis pointing up, and the supported IMU boards have *X* axis pointing to the pins side and *Z* axis pointing up from the component side:
+The drone has *X* axis pointing forward, *Y* axis pointing left, and *Z* axis pointing up, and the supported IMU boards have *X* axis pointing to the mounting holes side and *Z* axis pointing up from the component side:

 <img src="img/imu-axes.png" width="200">

@@ -122,10 +162,10 @@ Use the following table to set the parameters for common IMU orientations:

 |Orientation|Parameters|Orientation|Parameters|
 |:-:|-|-|-|
-|<img src="img/imu-rot-1.png" width="180">|`IMU_ROT_ROLL` = 0<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = 0    |<img src="img/imu-rot-5.png" width="180">|`IMU_ROT_ROLL` = 3.142<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = 0|
-|<img src="img/imu-rot-2.png" width="180">|`IMU_ROT_ROLL` = 0<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = 1.571|<img src="img/imu-rot-6.png" width="180">|`IMU_ROT_ROLL` = 3.142<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = -1.571|
-|<img src="img/imu-rot-3.png" width="180">|`IMU_ROT_ROLL` = 0<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = 3.142|<img src="img/imu-rot-7.png" width="180">|`IMU_ROT_ROLL` = 3.142<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = 3.142|
-|<img src="img/imu-rot-4.png" width="180"><br>☑️ **Default**|<br>`IMU_ROT_ROLL` = 0<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = -1.571|<img src="img/imu-rot-8.png" width="180">|`IMU_ROT_ROLL` = 3.142<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = 1.571|
+|<img src="img/imu-rot-3.png" width="180">|`IMU_ROT_ROLL` = 0<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = 0    |<img src="img/imu-rot-7.png" width="180">|`IMU_ROT_ROLL` = 3.142<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = 0|
+|<img src="img/imu-rot-2.png" width="180">|`IMU_ROT_ROLL` = 0<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = -1.571|<img src="img/imu-rot-6.png" width="180">|`IMU_ROT_ROLL` = 3.142<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = -1.571|
+|<img src="img/imu-rot-1.png" width="180">|`IMU_ROT_ROLL` = 0<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = 3.142|<img src="img/imu-rot-5.png" width="180">|`IMU_ROT_ROLL` = 3.142<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = 3.142|
+|<img src="img/imu-rot-4.png" width="180"><br>☑️ **Default**|<br>`IMU_ROT_ROLL` = 0<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = 1.571|<img src="img/imu-rot-8.png" width="180">|`IMU_ROT_ROLL` = 3.142<br>`IMU_ROT_PITCH` = 0<br>`IMU_ROT_YAW` = 1.571|

 ### Calibrate accelerometer

@@ -138,7 +178,9 @@ Before flight you need to calibrate the accelerometer:

 If using non-default motor pins, set the pin numbers using the parameters: `MOTOR_PIN_FL`, `MOTOR_PIN_FR`, `MOTOR_PIN_RL`, `MOTOR_PIN_RR` (front-left, front-right, rear-left, rear-right respectively).

-If using brushless motors and ESCs:
+#### Brushless motors
+
+If using brushless motors with ESCs:

 1. Set the appropriate PWM using the parameters: `MOT_PWM_STOP`, `MOT_PWM_MIN`, and `MOT_PWM_MAX` (1000, 1000, and 2000 is typical).
 2. Decrease the PWM frequency using the `MOT_PWM_FREQ` parameter (400 is typical).
@@ -146,6 +188,15 @@ If using brushless motors and ESCs:
 > [!CAUTION]
 > **Remove the props when configuring the motors!** If improperly configured, you may not be able to stop them.

+### Battery voltage monitoring (optional)
+
+ESP32 ADC can measure only up to 3.3 V, so you need to use a voltage divider to monitor the battery voltage. To enable voltage measurement, set the following parameters:
+
+1. `PWR_VOLT_PIN` — GPIO pin number where the voltage divider is connected (*-1* to disable).
+2. `PWR_VOLT_SCALE` — voltage divider coefficient (*2* for two equal resistors).
+
+After this setup, you should see the battery voltage in QGroundControl top panel or using `pw` command in the console.
+
 ### Important: check everything works

 1. Check the IMU is working: perform `imu` command in the console and check the output:
@@ -159,7 +210,7 @@ If using brushless motors and ESCs:

 2. Check the attitude estimation: connect to the drone using QGroundControl, rotate the drone in different orientations and check if the attitude estimation shown in QGroundControl is correct. Compare your attitude indicator (in the *large vertical* mode) to the video:

-    <a href="https://youtu.be/yVRN23-GISU"><img width=300 src="https://i3.ytimg.com/vi/yVRN23-GISU/maxresdefault.jpg"></a>
+   <a href="https://youtu.be/yVRN23-GISU"><img width=300 src="https://i3.ytimg.com/vi/yVRN23-GISU/maxresdefault.jpg"></a>

 3. Perform motor tests. Use the following commands **— remove the propellers before running the tests!**

@@ -177,10 +228,22 @@ If using brushless motors and ESCs:

 ## Setup remote control

-There are several ways to control the drone's flight: using **smartphone** (Wi-Fi), using **SBUS remote control**, or using **USB remote control** (Wi-Fi).
+There are several ways to control the drone's flight: using **smartphone** (Wi-Fi), using **SBUS remote control**, or using **USB remote control** (Wi-Fi/ESP-NOW).

 ### Control with a smartphone

+#### Using Mavlink Joystick app (Android)
+
+<img src="https://github.com/goldarte/mavlink-joystick/blob/master/app_screen.png?raw=true" width="400">
+
+1. Download and install [Mavlink Joystick app](https://github.com/goldarte/mavlink-joystick/releases/latest).
+2. Power the drone using the battery.
+3. Connect your smartphone to the appeared `flix` Wi-Fi network (password: `flixwifi`).
+4. Open Mavlink Joystick app. It should connect and begin showing the drone's telemetry automatically.
+5. Use the virtual joystick to fly the drone!
+
+#### Using QGroundControl app
+
 1. Install [QGroundControl mobile app](https://docs.qgroundcontrol.com/master/en/qgc-user-guide/getting_started/download_and_install.html#android) on your smartphone.
 2. Power the drone using the battery.
 3. Connect your smartphone to the appeared `flix` Wi-Fi network (password: `flixwifi`).
@@ -193,11 +256,11 @@ There are several ways to control the drone's flight: using **smartphone** (Wi-F

 ### Control with a remote control

-Before using SBUS-connected remote control you need to enable SBUS and calibrate it:
+If using SBUS-connected remote control you need to enable SBUS and calibrate it:

 1. Connect to the drone using QGroundControl.
 2. In parameters, set the `RC_RX_PIN` parameter to the GPIO pin number where the SBUS signal is connected, for example: 4. Negative value disables SBUS.
-3. Reboot the drone to apply changes.
+3. Check if the receiver is working using `rc` command in the console.
 4. Open the console, type `cr` command and follow the instructions to calibrate the remote control.
 5. Use the remote control to fly the drone!

@@ -210,7 +273,7 @@ If your drone doesn't have RC receiver installed, you can use USB remote control
 3. Power up the drone.
 4. Connect your computer to the appeared `flix` Wi-Fi network (password: `flixwifi`).
 5. Launch QGroundControl app. It should connect and begin showing the drone's telemetry automatically.
-6. Go the the QGroundControl menu ⇒ *Vehicle Setup* ⇒ *Joystick*. Calibrate you USB remote control there.
+6. Go to the QGroundControl menu ⇒ *Vehicle Setup* ⇒ *Joystick*. Calibrate your USB remote control there.
 7. Use the USB remote control to fly the drone!

 ## Flight
@@ -236,7 +299,7 @@ When finished flying, **disarm** the drone, moving the left stick to the bottom

 ### Flight modes

-Flight mode is changed using mode switch on the remote control (if configured) or using the console commands. The main flight mode is *STAB*.
+Flight mode is changed using mode switch on the remote control (if configured) or using the console commands. The main flight mode is *STAB*. In order to change modes using SBUS remote control, set the parameters: `CTL_FLT_MODE_0`, `CTL_FLT_MODE_1`, and `CTL_FLT_MODE_2` to required mode numbers (0 for *RAW*, 1 for *ACRO*, 2 for *STAB*, 3 for *AUTO*).

 #### STAB

@@ -257,7 +320,7 @@ In this mode, the pilot controls the angular rates. This control method is diffi

 In this mode, the pilot inputs are ignored (except the mode switch). The drone can be controlled using [pyflix](../tools/pyflix/) Python library, or by modifying the firmware to implement the needed behavior.

-If the pilot moves the control sticks, the drone will switch back to *STAB* mode.
+If the pilot moves the control sticks and mode switch is not configured, the drone will switch back to *STAB* mode.

 ## Wi-Fi configuration

@@ -267,11 +330,8 @@ The Wi-Fi mode is chosen using `WIFI_MODE` parameter in QGroundControl or in the

 * `0` — Wi-Fi is disabled.
 * `1` — Access Point mode *(AP)* — the drone creates a Wi-Fi network.
-* `2` — Client mode *(STA)* — the drone connects to an existing Wi-Fi network.
-* `3` — *ESP-NOW (not implemented yet)*.
-
-> [!WARNING]
-> Tests showed that Client mode may cause **additional delays** in remote control (due to retranslations), so it's generally not recommended.
+* `2` — Client mode *(STA)* — the drone connects to an existing Wi-Fi network (may cause additional delays, so generally not recommended).
+* `3` — ESP-NOW mode — the drone uses ESP-NOW protocol for communication.

 The SSID and password are configured using the `ap` and `sta` console commands:

@@ -293,9 +353,43 @@ Disabling Wi-Fi:
 p WIFI_MODE 0
 ```

+### Using ESP-NOW
+
+[ESP-NOW](https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-reference/network/esp_now.html) is a low level wireless communication protocol. It can provide lower latency, better reliability, and longer range than Wi-Fi. However, it requires a second ESP32 board to be used as a proxy for the computer.
+
+<img src="img/espnow-connection.jpg" width="600">
+
+To setup ESP-NOW communication:
+
+1. Flash the second ESP32 board with ESP-NOW proxy sketch: [`tools/espnow-proxy/espnow-proxy.ino`](../tools/espnow-proxy/espnow-proxy.ino). Use Arduino IDE or command line: `make upload_proxy`.
+
+2. Open Serial Monitor in Arduino IDE or use `make monitor` command. The ESP32 will print its MAC address and generated encryption key, for example:
+
+   ```
+   espnow 7a:c8:e3:eb:bf:e9 &PiuSysxP9+$L&5E
+   ```
+
+   Run this line as a console command on each drone you want to bind to this proxy board. [The maximum number](https://github.com/espressif/esp-idf/blob/e95cab4be8fd293e3f3323181e7a2280874da6f7/components/esp_wifi/include/esp_now.h#L32-L33) of simultaneously connected drones is 20 (unencrypted) or 6 (encrypted).
+
+3. Set the `WIFI_MODE` parameter to `3` on the drone:
+
+   ```
+   p WIFI_MODE 3
+   ```
+
+4. Go to the QGroundControl menu ⇒ *Application Settings* ⇒ *Comm Links*, add new link with the following settings:
+   * Name: ESP32.
+   * Type: Serial.
+   * Serial Port: choose the port of the proxy ESP32 board, e. g. `/dev/cu.usbserial-0001`.
+   * Baud Rate: 115200.
+5. Click *Save*, click *Connect*. QGroundControl should connect to the drone using ESP-NOW and begin showing the telemetry.
+
+> [!TIP]
+> Make sure Arduino IDE is not running when using ESP-NOW proxy board, as it may block the serial port.
+
 ## Flight log

-After the flight, you can download the flight log for analysis wirelessly. Use the following command on your computer for that:
+After the flight, you can download the flight log wirelessly for analysis. Use the following command on your computer for that:

 ```bash
 make log
@@ -4,6 +4,71 @@ This page contains user-built drones based on the Flix project. Publish your pro

 ---

+Author: [Oleg1405](https://t.me/Oleg1405).<br>
+Description: ESP32 Mini, MPU-6500 IMU, boost converter, BT2.0 power connector, 65 mm props, BetaFPV ELRS Lite Receiver, Radiomaster Pocket + Mavlink Joystick (Android) control.
+
+<img src="img/user/oleg1405/1.jpg" height=300>
+
+[Flight video](https://www.youtube.com/shorts/rbXV4sHbpso).
+
+---
+
+Author: Alican Erüst.<br>
+Description: QX95 mm frame, 55 mm propellers, 3.7 V 25C 1050 mAh LiPo battery, MPU6050 IMU, Logitech F310 gamepad controller, with a total quadcopter weight of 66 g.
+
+<img src="img/user/alicanerus/1.jpg" height=200> <img src="img/user/alicanerus/2.jpg" height=200> <img src="img/user/alicanerus/3.jpg" height=200>
+
+[Flight video](https://drive.google.com/file/d/1k0WeWTKnCAfaugkX7LcmNxsUuq79RL8Z/view?usp=sharing).
+
+---
+
+Author: [Неруш Михаил](https://t.me/NerushMV).<br>
+Description: custom frame made of 4 mm plywood, 8520 brushed motors, 75 mm propellers, MPU-6500. FlySky FS-i6X with ESP32-based adapter for ESP-NOW communication (using PPM output).<br>
+Sources and materials: [link](https://drive.google.com/drive/folders/1uWiDcuorLrtVs_IIR7Y13omij-7Q1nx8).
+
+<img src="img/user/nerush/1.jpg" height=200> <img src="img/user/nerush/2.jpg" height=200>
+
+[Flight video](https://drive.google.com/file/d/1jRXeGx34lJpUfw0GKLQeIzkWZvooQJSE/view?usp=sharing).
+
+---
+
+Author: [Konstantinos Paraskevas](https://github.com/Frapais).<br>
+Description: drone with a custom single-boarded airframe, extending the [Sprig-C3 module](https://github.com/Frapais/Sprig-C3).
+ESP32-C3 microcontroller, ICM-20948 IMU, on-board fuel-gauge, status LED indicator.<br>
+Repository with all the code and PCB sources: https://github.com/Frapais/Sprig-Drone.
+
+<img src="img/user/kostas/1.jpg" height=150> <img src="img/user/kostas/2.jpg" height=150>
+
+Detailed video about making the drone:
+
+<a href="https://youtu.be/82Q-uBq6s48"><img width=400 src="https://i3.ytimg.com/vi/82Q-uBq6s48/maxresdefault.jpg"></a>
+
+---
+
+Author: [Awab Anas](http://t.me/AW_VENOM).<br>
+Description: ESP32 D1 Mini, MPU-6050, 8520 3.7V brushed motors, 55 mm propellers, battery li-po 1200 mAh, controlling via [Mavlink Joystick app](https://github.com/goldarte/mavlink-joystick/releases/latest).<br>
+[Flight validation](https://drive.google.com/file/d/12z0jfctZDBA6b5UKCG0Uje5rAxj6DhF-/view?usp=sharing).
+
+<img src="img/user/aw_venom/1.jpg" height=200>
+
+---
+
+Author: [Ina Tix](https://t.me/ina_tix).<br>
+Description: XR2981 based DC-DC converter, ELRS MINI 2.4GHz RX SX1280 receiver (SBUS interface), Radiomaster TX12 remote control.<br>
+[Flight validation](https://drive.google.com/file/d/1yqkKNuz4R_yxGqUNQxVpixJbXqEEcUSj/view?usp=share_link).
+
+<img src="img/user/ina_tix/1.jpg" height=200> <img src="img/user/ina_tix/2.jpg" height=200> <img src="img/user/ina_tix/3.jpg" height=200>
+
+---
+
+Author: Oleg Kalachev.<br>
+Description: the first attempt on making an official PCB based Flix drone (Flix2 board). The IMU is not working on this version, so an external MPU-6050 board was used, therefore considered as **Flix version 1.5**.<br>
+[Flight video](https://drive.google.com/file/d/1R7tuUsFmPY0CGcOCFfMFaCp9kR49K3bl/view?usp=sharing).
+
+<img src="img/flix1.5.jpg" width=300>
+
+---
+
 Author: [FanBy0ru](https://https://github.com/FanBy0ru).<br>
 Description: custom 3D-printed frame.<br>
 Frame STLs and flight validation: https://cults3d.com/en/3d-model/gadget/armature-pour-flix-drone.
@@ -41,6 +106,17 @@ Author: [goldarte](https://t.me/goldarte).<br>

 ---

+Author: [malagis](https://oshwhub.com/malagis).<br>
+
+A Chinese custom PCB version of Flix with a big community of users, lots of materials and modifications.
+
+Main project's page: https://oshwhub.com/malagis/esp32-mini-plane.<br>
+Video about the project: https://www.bilibili.com/video/BV14vyqBFEJn/.
+
+<img src="img/user/malagis/1.jpg" height=200> <img src="img/user/malagis/2.jpg" height=200> <img src="img/user/malagis/3.jpg" height=200>
+
+---
+
 ## School 548 course

 Special course on quadcopter design and engineering took place in october-november 2025 in School 548, Moscow. The course included UAV control theory, electronics, drone assembly and setup practice, using the Flix project.
@@ -6,53 +6,64 @@
 #include "pid.h"
 #include "vector.h"
 #include "util.h"
-#include "lpf.h"
+#include "filter.h"

 extern const int MOTOR_REAR_LEFT, MOTOR_REAR_RIGHT, MOTOR_FRONT_RIGHT, MOTOR_FRONT_LEFT;
 extern const int RAW, ACRO, STAB, AUTO;
+extern const int W_AP, W_STA, W_ESPNOW;
 extern float t, dt, loopRate;
 extern uint16_t channels[16];
 extern float controlTime;
 extern int mode;
 extern bool armed;
 extern LowPassFilter<Vector> gyroBiasFilter;
+extern float voltage;

 const char* motd =
-"\nWelcome to\n"
 " _______  __       __  ___   ___\n"
 "|   ____||  |     |  | \\  \\ /  /\n"
 "|  |__   |  |     |  |  \\  V  /\n"
 "|   __|  |  |     |  |   >   <\n"
 "|  |     |  `----.|  |  /  .  \\\n"
 "|__|     |_______||__| /__/ \\__\\\n\n"
+"(C) Oleg Kalachev\n"
+"https://github.com/okalachev/flix\n\n"
 "Commands:\n\n"
 "help - show help\n"
 "p - show all parameters\n"
-"p <name> - show parameter\n"
+"p <str> - show parameters starting with str\n"
 "p <name> <value> - set parameter\n"
 "preset - reset parameters\n"
 "time - show time info\n"
-"ps - show pitch/roll/yaw\n"
-"psq - show attitude quaternion\n"
 "imu - show IMU data\n"
+"ca - calibrate accel\n"
+"st - show state estimation\n"
 "arm - arm the drone\n"
 "disarm - disarm the drone\n"
 "raw/stab/acro/auto - set mode\n"
 "rc - show RC data\n"
-"wifi - show Wi-Fi info\n"
-"ap <ssid> <password> - setup Wi-Fi access point\n"
-"sta <ssid> <password> - setup Wi-Fi client mode\n"
-"mot - show motor output\n"
-"log [dump] - print log header [and data]\n"
 "cr - calibrate RC\n"
-"ca - calibrate accel\n"
-"mfr, mfl, mrr, mrl - test motor (remove props)\n"
+"pw - show power info\n"
+"wifi - show Wi-Fi info\n"
+"wifi ap/sta/espnow/off - set Wi-Fi mode\n"
+"ap <ssid> <password> - configure Wi-Fi access point\n"
+"sta <ssid> <password> - configure Wi-Fi client mode\n"
+"espnow <mac> [<key>] - configure ESP-NOW peer\n"
+"mot - show motor output\n"
+"mfr/mfl/mrr/mrl [<thrust>] - test motor (remove props)\n"
+"log [dump] - print log header [and data]\n"
+"log - show log info\n"
+"log header - show log header\n"
+"log reset - reset log\n"
+"log <name> <rate> - setup log topic rate\n"
+"l <str> - show log values starting with str\n"
+"l expose <name> - expose log value to telemetry\n"
 "sys - show system info\n"
 "reset - reset drone's state\n"
 "reboot - reboot the drone\n";

 void print(const char* format, ...) {
-	char buf[1000];
+	char buf[3000];
 	va_list args;
 	va_start(args, format);
 	vsnprintf(buf, sizeof(buf), format, args);
@@ -87,16 +98,14 @@ void doCommand(String str, bool echo = false) {
 	// execute command
 	if (command == "help" || command == "motd") {
 		print("%s\n", motd);
-	} else if (command == "p" && arg0 == "") {
-		printParameters();
-	} else if (command == "p" && arg0 != "" && arg1 == "") {
-		print("%s = %g\n", arg0.c_str(), getParameter(arg0.c_str()));
+	} else if (command == "p" && arg1 == "") {
+		printParameters(arg0.c_str());
 	} else if (command == "p") {
 		bool success = setParameter(arg0.c_str(), arg1.toFloat());
 		if (success) {
 			print("%s = %g\n", arg0.c_str(), getParameter(arg0.c_str()));
 		} else {
-			print("Parameter not found: %s\n", arg0.c_str());
+			print("Cannot set parameter: %s\n", arg0.c_str());
 		}
 	} else if (command == "preset") {
 		resetParameters();
@@ -104,15 +113,15 @@ void doCommand(String str, bool echo = false) {
 		print("Time: %f\n", t);
 		print("Loop rate: %.0f\n", loopRate);
 		print("dt: %f\n", dt);
-	} else if (command == "ps") {
-		Vector a = attitude.toEuler();
-		print("roll: %f pitch: %f yaw: %f\n", degrees(a.x), degrees(a.y), degrees(a.z));
-	} else if (command == "psq") {
-		print("qw: %f qx: %f qy: %f qz: %f\n", attitude.w, attitude.x, attitude.y, attitude.z);
 	} else if (command == "imu") {
 		printIMUInfo();
 		printIMUCalibration();
 		print("landed: %d\n", landed);
+	} else if (command == "st") {
+		print("rates: %g %g %g\n", rates.x, rates.y, rates.z);
+		print("attitude: %g %g %g %g\n", attitude.w, attitude.x, attitude.y, attitude.z);
+		print("roll: %g° pitch: %g° yaw: %g°\n", degrees(attitude.getRoll()), degrees(attitude.getPitch()), degrees(attitude.getYaw()));
+		print("landed: %d\n", landed);
 	} else if (command == "arm") {
 		armed = true;
 	} else if (command == "disarm") {
@@ -135,37 +144,59 @@ void doCommand(String str, bool echo = false) {
 		print("time: %.1f\n", controlTime);
 		print("mode: %s\n", getModeName());
 		print("armed: %d\n", armed);
-	} else if (command == "wifi") {
+	} else if (command == "pw") {
+		print("Voltage: %.1f V\n", voltage);
+	} else if (command == "wifi" && arg0 == "") {
 		printWiFiInfo();
+	} else if (command == "wifi") {
+		setWiFiMode(arg0);
 	} else if (command == "ap") {
-		configWiFi(true, arg0.c_str(), arg1.c_str());
+		configWiFi(W_AP, arg0.c_str(), arg1.c_str());
 	} else if (command == "sta") {
-		configWiFi(false, arg0.c_str(), arg1.c_str());
+		configWiFi(W_STA, arg0.c_str(), arg1.c_str());
+	} else if (command == "espnow") {
+		configWiFi(W_ESPNOW, arg0.c_str(), arg1.c_str());
 	} else if (command == "mot") {
 		print("front-right %g front-left %g rear-right %g rear-left %g\n",
 			motors[MOTOR_FRONT_RIGHT], motors[MOTOR_FRONT_LEFT], motors[MOTOR_REAR_RIGHT], motors[MOTOR_REAR_LEFT]);
-	} else if (command == "log") {
+	} else if (command == "log" && arg0 == "") {
+		printLogInfo();
+	} else if (command == "log" && arg1 != "") {
+		configLogThrottle(arg0.c_str(), arg1.toFloat());
+	} else if (command == "log" && arg0 == "header") {
 		printLogHeader();
-		if (arg0 == "dump") printLogData();
+	} else if (command == "log" && arg0 == "reset") {
+		resetLog();
+	} else if (command == "l" && arg0 == "expose" && arg1 != "") {
+		exposeLogValue(arg1.c_str());
+	} else if (command == "l") {
+		printLogValues(arg0.c_str());
 	} else if (command == "cr") {
 		calibrateRC();
 	} else if (command == "ca") {
 		calibrateAccel();
 	} else if (command == "mfr") {
-		testMotor(MOTOR_FRONT_RIGHT);
+		testMotor(MOTOR_FRONT_RIGHT, arg0.isEmpty() ? 0.2 : arg0.toFloat());
 	} else if (command == "mfl") {
-		testMotor(MOTOR_FRONT_LEFT);
+		testMotor(MOTOR_FRONT_LEFT, arg0.isEmpty() ? 0.2 : arg0.toFloat());
 	} else if (command == "mrr") {
-		testMotor(MOTOR_REAR_RIGHT);
+		testMotor(MOTOR_REAR_RIGHT, arg0.isEmpty() ? 0.2 : arg0.toFloat());
 	} else if (command == "mrl") {
-		testMotor(MOTOR_REAR_LEFT);
+		testMotor(MOTOR_REAR_LEFT, arg0.isEmpty() ? 0.2 : arg0.toFloat());
 	} else if (command == "sys") {
 #ifdef ESP32
 		print("Chip: %s\n", ESP.getChipModel());
 		print("Temperature: %.1f °C\n", temperatureRead());
-		print("Free heap: %d\n", ESP.getFreeHeap());
+		print("Total RAM: %d KB\n", ESP.getHeapSize() / 1024);
+		print("Free heap: %d KB\n", ESP.getFreeHeap() / 1024);
+		print("PSRAM: %d KB\n", ESP.getPsramSize() / 1024);
+		print("Free PSRAM: %d KB\n", ESP.getFreePsram() / 1024);
+#ifdef VERSION
+		print("Version: %s\n", STRINGIFY(VERSION));
+#endif
+		print("Build date: " __DATE__ " " __TIME__ "\n");
 		// Print tasks table
-		print("Num  Task                Stack  Prio  Core  CPU%%\n");
+		print("Num  Task                MinSt  Prio  Core  CPU%%\n");
 		int taskCount = uxTaskGetNumberOfTasks();
 		TaskStatus_t *systemState = new TaskStatus_t[taskCount];
 		uint32_t totalRunTime;
@@ -174,7 +205,7 @@ void doCommand(String str, bool echo = false) {
 			String core = systemState[i].xCoreID == tskNO_AFFINITY ? "*" : String(systemState[i].xCoreID);
 			int cpuPercentage = systemState[i].ulRunTimeCounter / (totalRunTime / 100);
 			print("%-5d%-20s%-7d%-6d%-6s%d\n",systemState[i].xTaskNumber, systemState[i].pcTaskName,
-				systemState[i].usStackHighWaterMark, systemState[i].uxCurrentPriority, core, cpuPercentage);
+				systemState[i].usStackHighWaterMark, systemState[i].uxCurrentPriority, core.c_str(), cpuPercentage);
 		}
 		delete[] systemState;
 #endif
@@ -199,7 +230,7 @@ void handleInput() {

 	while (Serial.available()) {
 		char c = Serial.read();
-		if (c == '\n') {
+		if (c == '\n' || c == '\r') {
 			doCommand(input);
 			input.clear();
 		} else {
@@ -0,0 +1,33 @@
+// Copyright (c) 2026 Oleg Kalachev <okalachev@gmail.com>
+// Repository: https://github.com/okalachev/flix
+
+// Parameter defaults
+
+#pragma once
+
+void setDefaults() {
+	// Set defaults here
+
+	#if defined(CONFIG_IDF_TARGET_ESP32S3) || defined(CONFIG_IDF_TARGET_ESP32C3)
+		pwmFrequency = 38000;
+	#endif
+
+	#ifdef CONFIG_IDF_TARGET_ESP32
+		// classic esp32 configuration
+		motorPins[0] = 12;
+		motorPins[1] = 13;
+		motorPins[2] = 14;
+		motorPins[3] = 15;
+	#endif
+
+	#ifdef FLIX2
+		imuModel = 4; // ICM-40609-D
+		imuIntPin = 10;
+		imuCsPin = 14;
+		voltagePin = 3;
+		motorPins[0] = 41;
+		motorPins[1] = 7;
+		motorPins[2] = 18;
+		motorPins[3] = 38;
+	#endif
+}
@@ -6,34 +6,9 @@
 #include "vector.h"
 #include "quaternion.h"
 #include "pid.h"
-#include "lpf.h"
+#include "filter.h"
 #include "util.h"

-#define PITCHRATE_P 0.05
-#define PITCHRATE_I 0.2
-#define PITCHRATE_D 0.001
-#define PITCHRATE_I_LIM 0.3
-#define ROLLRATE_P PITCHRATE_P
-#define ROLLRATE_I PITCHRATE_I
-#define ROLLRATE_D PITCHRATE_D
-#define ROLLRATE_I_LIM PITCHRATE_I_LIM
-#define YAWRATE_P 0.3
-#define YAWRATE_I 0.0
-#define YAWRATE_D 0.0
-#define YAWRATE_I_LIM 0.3
-#define ROLL_P 6
-#define ROLL_I 0
-#define ROLL_D 0
-#define PITCH_P ROLL_P
-#define PITCH_I ROLL_I
-#define PITCH_D ROLL_D
-#define YAW_P 3
-#define PITCHRATE_MAX radians(360)
-#define ROLLRATE_MAX radians(360)
-#define YAWRATE_MAX radians(300)
-#define TILT_MAX radians(30)
-#define RATES_D_LPF_ALPHA 0.2 // cutoff frequency ~ 40 Hz
-
 const int RAW = 0, ACRO = 1, STAB = 2, AUTO = 3; // flight modes
 int mode = STAB;
 bool armed = false;
@@ -41,17 +16,17 @@ bool armed = false;
 Quaternion attitudeTarget;
 Vector ratesTarget;
 Vector ratesExtra; // feedforward rates
-Vector torqueTarget;
+Vector torqueTarget; // 0 - no torque, 1 - maximum torque
 float thrustTarget;

-PID rollRatePID(ROLLRATE_P, ROLLRATE_I, ROLLRATE_D, ROLLRATE_I_LIM, RATES_D_LPF_ALPHA);
-PID pitchRatePID(PITCHRATE_P, PITCHRATE_I, PITCHRATE_D, PITCHRATE_I_LIM, RATES_D_LPF_ALPHA);
-PID yawRatePID(YAWRATE_P, YAWRATE_I, YAWRATE_D);
-PID rollPID(ROLL_P, ROLL_I, ROLL_D);
-PID pitchPID(PITCH_P, PITCH_I, PITCH_D);
-PID yawPID(YAW_P, 0, 0);
-Vector maxRate(ROLLRATE_MAX, PITCHRATE_MAX, YAWRATE_MAX);
-float tiltMax = TILT_MAX;
+PID rollRatePID(0.05, 0.2, 0.001, 0.3, 0.2);
+PID pitchRatePID(0.05, 0.2, 0.001, 0.3, 0.2);
+PID yawRatePID(0.3, 0, 0, 0.3);
+PID rollPID(6);
+PID pitchPID(6);
+PID yawPID(3);
+Vector maxRate(radians(360), radians(360), radians(360));
+float tiltMax = radians(30);
 int flightModes[] = {STAB, STAB, STAB}; // map for rc mode switch

 extern const int MOTOR_REAR_LEFT, MOTOR_REAR_RIGHT, MOTOR_FRONT_RIGHT, MOTOR_FRONT_LEFT;
@@ -67,7 +42,7 @@ void control() {

 void interpretControls() {
 	if (controlMode < 0.25) mode = flightModes[0];
-	else if (controlMode < 0.75) mode = flightModes[1];
+	else if (controlMode <= 0.75) mode = flightModes[1];
 	else if (controlMode > 0.75) mode = flightModes[2];

 	if (mode == AUTO) return; // pilot is not effective in AUTO mode
@@ -149,12 +124,26 @@ void controlTorque() {
 	motors[MOTOR_REAR_LEFT] = thrustTarget + torqueTarget.x + torqueTarget.y - torqueTarget.z;
 	motors[MOTOR_REAR_RIGHT] = thrustTarget - torqueTarget.x + torqueTarget.y + torqueTarget.z;

+	// Prioritize angle control over thrust control
+	desaturate(motors[MOTOR_FRONT_LEFT], motors[MOTOR_FRONT_RIGHT], motors[MOTOR_REAR_LEFT], motors[MOTOR_REAR_RIGHT]);
+
 	motors[0] = constrain(motors[0], 0, 1);
 	motors[1] = constrain(motors[1], 0, 1);
 	motors[2] = constrain(motors[2], 0, 1);
 	motors[3] = constrain(motors[3], 0, 1);
 }

+void desaturate(float& a, float& b, float& c, float& d) {
+	float maxThrust = max(max(a, b), max(c, d));
+	if (maxThrust > 1) {
+		float diff = maxThrust - 1;
+		a -= diff;
+		b -= diff;
+		c -= diff;
+		d -= diff;
+	}
+}
+
 const char* getModeName() {
 	switch (mode) {
 		case RAW: return "RAW";
@@ -5,7 +5,7 @@

 #include "quaternion.h"
 #include "vector.h"
-#include "lpf.h"
+#include "filter.h"
 #include "util.h"

 Vector rates; // estimated angular rates, rad/s
@@ -13,16 +13,25 @@ Quaternion attitude; // estimated attitude
 bool landed;

 float accWeight = 0.003;
+float levelWeight = 0.0002;
 LowPassFilter<Vector> ratesFilter(0.2); // cutoff frequency ~ 40 Hz
+NotchFilter<Vector> ratesNotch(382, 40);
+
+void setupEstimate() {
+	print("Setup estimation\n");
+	ratesNotch.reset();
+}

 void estimate() {
 	applyGyro();
 	applyAcc();
+	applyLevel();
 }

 void applyGyro() {
 	// filter gyro to get angular rates
 	rates = ratesFilter.update(gyro);
+	rates = ratesNotch.update(rates);

 	// apply rates to attitude
 	attitude = Quaternion::rotate(attitude, Quaternion::fromRotationVector(rates * dt));
@@ -30,8 +39,7 @@ void applyGyro() {

 void applyAcc() {
 	// test should we apply accelerometer gravity correction
-	float accNorm = acc.norm();
-	landed = !motorsActive() && abs(accNorm - ONE_G) < ONE_G * 0.1f;
+	landed = !motorsActive() && abs(acc.norm() - ONE_G) < ONE_G * 0.1f;

 	if (!landed) return;

@@ -42,3 +50,13 @@ void applyAcc() {
 	// apply correction
 	attitude = Quaternion::rotate(attitude, Quaternion::fromRotationVector(correction));
 }
+
+void applyLevel() {
+	if (landed) return;
+	if (thrustTarget < 0.1) return; // skip at idle thrust
+
+	// assume the pilot keeps the drone more or less level in flight
+	Vector up = Quaternion::rotateVector(Vector(0, 0, 1), attitude);
+	Vector correction = Vector::rotationVectorBetween(Vector(0, 0, 1), up) * levelWeight;
+	attitude = Quaternion::rotate(attitude, Quaternion::fromRotationVector(correction));
+}
@@ -0,0 +1,98 @@
+// Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
+// Repository: https://github.com/okalachev/flix
+
+// Low pass and notch filters
+
+#pragma once
+
+template <typename T> // Using template to make the filter usable for scalar and vector values
+class LowPassFilter {
+public:
+	float alpha; // smoothing constant, 1 means filter disabled
+	T output;
+
+	LowPassFilter(float alpha): alpha(alpha) {};
+
+	T update(const T input) {
+		if (!init) {
+			init = true;
+			return output = input;
+		}
+		return output += alpha * (input - output);
+	}
+
+	void setCutOffFrequency(float cutOffFreq, float dt) {
+		alpha = 1 - exp(-2 * PI * cutOffFreq * dt);
+	}
+
+	void reset() {
+		init = false;
+	}
+
+private:
+	bool init = false;
+};
+
+template <typename T>
+class NotchFilter {
+public:
+	float frequency;
+	float bandwidth;
+	T output;
+
+	NotchFilter(float frequency, float bandwidth): frequency(frequency), bandwidth(bandwidth) {
+		reset();
+	};
+
+	T update(const T input) {
+		if (frequency <= 0 || bandwidth <= 0) return input;
+
+		if (!init) {
+			init = true;
+			x1 = x2 = input;
+			y1 = y2 = input;
+			return output = input;
+		}
+
+		output = b0 * input + b1 * x1 + b2 * x2 - a1 * y1 - a2 * y2;
+
+		x2 = x1;
+		x1 = input;
+		y2 = y1;
+		y1 = output;
+
+		return output;
+	}
+
+	void reset() {
+		const float dt = 0.001f;
+		float f = frequency;
+		float bw = bandwidth;
+		if (f < 0) f = 0;
+		if (bw < 1e-6f) bw = 1e-6f;
+
+		float q = f / bw;
+		if (q < 1e-3f) q = 1e-3f;
+
+		const float w0 = 2.0f * PI * f * dt;
+		const float c = cos(w0);
+		const float s = sin(w0);
+		const float alpha = s / (2.0f * q);
+
+		const float a0 = 1.0f + alpha;
+		const float invA0 = 1.0f / a0;
+
+		b0 = 1.0f * invA0;
+		b1 = -2.0f * c * invA0;
+		b2 = 1.0f * invA0;
+		a1 = -2.0f * c * invA0;
+		a2 = (1.0f - alpha) * invA0;
+
+		init = false;
+	}
+
+private:
+	float b0, b1, b2, a1, a2;
+	T x1, x2, y1, y2;
+	bool init = false;
+};
@@ -17,15 +17,17 @@ extern float motors[4];

 void setup() {
 	Serial.begin(115200);
-	print("Initializing flix\n");
-	disableBrownOut();
+	print("Initializing Flix\n");
 	setupParameters();
+	setupPower();
 	setupLED();
 	setLED(true);
 	setupMotors();
 	setupWiFi();
 	setupIMU();
 	setupRC();
+	setupEstimate();
+	setupLog();
 	setLED(false);
 	print("Initializing complete\n");
 }
@@ -39,6 +41,7 @@ void loop() {
 	sendMotors();
 	handleInput();
 	processMavlink();
-	logData();
+	readVoltage();
+	loopLog();
 	syncParameters();
 }
@@ -4,13 +4,18 @@
 // Work with the IMU sensor

 #include <SPI.h>
+#include <Wire.h>
 #include <FlixPeriph.h>
 #include "vector.h"
-#include "lpf.h"
+#include "filter.h"
 #include "util.h"

-MPU9250 imu(SPI);
-Vector imuRotation(0, 0, -PI / 2); // imu orientation as Euler angles
+IMU *imu;
+int imuModel = -1; // 1 - MPU9250, 2 - ICM20948, 3 - MPU6050, 4 - ICM40609D
+int imuBus = 0; // 0 - SPI, 1 - I2C
+int imuSckPin = SCK, imuMisoPin = MISO, imuMosiPin = MOSI, imuCsPin = SS, imuIntPin = -1;
+int imuSdaPin = SDA, imuSclPin = SCL;
+Vector imuRotation(0, 0, PI / 2); // imu orientation as Euler angles

 Vector gyro; // gyroscope output, rad/s
 Vector gyroBias;
@@ -23,27 +28,42 @@ LowPassFilter<Vector> gyroBiasFilter(0.001);

 void setupIMU() {
 	print("Setup IMU\n");
-	imu.begin();
+	free(imu);
+	if (imuModel == 3) imuBus = 1; // MPU6050 is I2C only
+
+	if (imuBus == 0) {
+		// SPI connection
+		SPI.begin(imuSckPin, imuMisoPin, imuMosiPin);
+		imu = IMU::create(imuModel, SPI, imuCsPin, imuIntPin);
+	} else {
+		// I2C connection
+		Wire.setPins(imuSdaPin, imuSclPin);
+		imu = IMU::create(imuModel, Wire, imuIntPin);
+	}
+
+	imu->begin();
 	configureIMU();
 }

 void configureIMU() {
-	imu.setAccelRange(imu.ACCEL_RANGE_4G);
-	imu.setGyroRange(imu.GYRO_RANGE_2000DPS);
-	imu.setDLPF(imu.DLPF_MAX);
-	imu.setRate(imu.RATE_1KHZ_APPROX);
-	imu.setupInterrupt();
+	imu->setAccelRange(IMU::ACCEL_RANGE_4G);
+	imu->setGyroRange(IMU::GYRO_RANGE_2000DPS);
+	imu->setDLPF(IMU::DLPF_MAX);
+	imu->setRate(IMU::RATE_1KHZ_APPROX);
+	imu->setupInterrupt();
 }

 void readIMU() {
-	imu.waitForData();
-	imu.getGyro(gyro.x, gyro.y, gyro.z);
-	imu.getAccel(acc.x, acc.y, acc.z);
+	imu->waitForData();
+	imu->getGyro(gyro.x, gyro.y, gyro.z);
+	imu->getAccel(acc.x, acc.y, acc.z);
 	calibrateGyroOnce();
-	// apply scale and bias
+
+	// Apply scale and bias
 	acc = (acc - accBias) / accScale;
 	gyro = gyro - gyroBias;
-	// rotate to body frame
+
+	// Rotate to body frame
 	Quaternion rotation = Quaternion::fromEuler(imuRotation);
 	acc = Quaternion::rotateVector(acc, rotation.inversed());
 	gyro = Quaternion::rotateVector(gyro, rotation.inversed());
@@ -52,12 +72,13 @@ void readIMU() {
 void calibrateGyroOnce() {
 	static Delay landedDelay(2);
 	if (!landedDelay.update(landed)) return; // calibrate only if definitely stationary
+
 	gyroBias = gyroBiasFilter.update(gyro);
 }

 void calibrateAccel() {
 	print("Calibrating accelerometer\n");
-	imu.setAccelRange(imu.ACCEL_RANGE_2G); // the most sensitive mode
+	imu->setAccelRange(IMU::ACCEL_RANGE_2G); // the most sensitive mode

 	print("1/6 Place level [8 sec]\n");
 	pause(8);
@@ -91,9 +112,9 @@ void calibrateAccelOnce() {
 	// Compute the average of the accelerometer readings
 	acc = Vector(0, 0, 0);
 	for (int i = 0; i < samples; i++) {
-		imu.waitForData();
+		imu->waitForData();
 		Vector sample;
-		imu.getAccel(sample.x, sample.y, sample.z);
+		imu->getAccel(sample.x, sample.y, sample.z);
 		acc = acc + sample;
 	}
 	acc = acc / samples;
@@ -105,6 +126,7 @@ void calibrateAccelOnce() {
 	if (acc.x < accMin.x) accMin.x = acc.x;
 	if (acc.y < accMin.y) accMin.y = acc.y;
 	if (acc.z < accMin.z) accMin.z = acc.z;
+
 	// Compute scale and bias
 	accScale = (accMax - accMin) / 2 / ONE_G;
 	accBias = (accMax + accMin) / 2;
@@ -117,16 +139,18 @@ void printIMUCalibration() {
 }

 void printIMUInfo() {
-	imu.status() ? print("status: ERROR %d\n", imu.status()) : print("status: OK\n");
-	print("model: %s\n", imu.getModel());
-	print("who am I: 0x%02X\n", imu.whoAmI());
+	imu->status() ? print("status: ERROR %d\n", imu->status()) : print("status: OK\n");
+	print("model: %s\n", imu->getModel());
+	print("who am I: 0x%02X\n", imu->whoAmI());
 	print("rate: %.0f\n", loopRate);
-	print("gyro: %f %f %f\n", rates.x, rates.y, rates.z);
+	print("interrupt mode: %s\n", imuIntPin != -1 ? "pin" : "timer");
+	print("temperature: %.1f °C\n", imu->getTemp());
+	print("gyro: %f %f %f\n", gyro.x, gyro.y, gyro.z);
 	print("acc: %f %f %f\n", acc.x, acc.y, acc.z);
-	imu.waitForData();
+	imu->waitForData();
 	Vector rawGyro, rawAcc;
-	imu.getGyro(rawGyro.x, rawGyro.y, rawGyro.z);
-	imu.getAccel(rawAcc.x, rawAcc.y, rawAcc.z);
+	imu->getGyro(rawGyro.x, rawGyro.y, rawGyro.z);
+	imu->getAccel(rawAcc.x, rawAcc.y, rawAcc.z);
 	print("raw gyro: %f %f %f\n", rawGyro.x, rawGyro.y, rawGyro.z);
 	print("raw acc: %f %f %f\n", rawAcc.x, rawAcc.y, rawAcc.z);
 }
@@ -1,77 +1,272 @@
 // Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
 // Repository: https://github.com/okalachev/flix

-// In-RAM logging
+// Logging subsystem

 #include "vector.h"
 #include "util.h"

-#define LOG_RATE 100
-#define LOG_DURATION 10
-#define LOG_SIZE LOG_DURATION * LOG_RATE
+int logMemory = 0; // 0 - RAM, 1 - PSRAM, -1 - disabled
+float logUsage = 0.5; // fraction of free memory to use for log

-Vector attitudeEuler;
-Vector attitudeTargetEuler;
-
-struct LogEntry {
+struct LogValue {
 	const char *name;
-	float *value;
+	Value value;
+	float lastValue = NAN;
+	bool logged = true; // if false, use only for triggering log update
+	LogValue() : name(nullptr), value() {}; // empty value constructor
+	template <typename T>
+	LogValue(const char *name, T value, bool logged = true) : name(name), value(value), logged(logged) {};
 };

-LogEntry logEntries[] = {
-	{"t", &t},
-	{"rates.x", &rates.x},
-	{"rates.y", &rates.y},
-	{"rates.z", &rates.z},
-	{"ratesTarget.x", &ratesTarget.x},
-	{"ratesTarget.y", &ratesTarget.y},
-	{"ratesTarget.z", &ratesTarget.z},
-	{"attitude.x", &attitudeEuler.x},
-	{"attitude.y", &attitudeEuler.y},
-	{"attitude.z", &attitudeEuler.z},
-	{"attitudeTarget.x", &attitudeTargetEuler.x},
-	{"attitudeTarget.y", &attitudeTargetEuler.y},
-	{"attitudeTarget.z", &attitudeTargetEuler.z},
-	{"thrustTarget", &thrustTarget}
+struct LogTopic {
+	LogValue values[10];
+	int length = 0; // number of logged values
+	float throttle; // max update rate, Hz
+	float lastUpdate = -INFINITY;
+
+	LogTopic(float throttle, LogValue v0, LogValue v1 = {}, LogValue v2 = {}, LogValue v3 = {}, LogValue v4 = {}, LogValue v5 = {}, LogValue v6 = {}, LogValue v7 = {}, LogValue v8 = {}, LogValue v9 = {}) :
+		throttle(throttle), values{v0, v1, v2, v3, v4, v5, v6, v7, v8, v9} {
+			// Count logged values
+			for (auto& v : values) {
+				if (v.name == nullptr) break;
+				if (v.logged) length++;
+			}
+		};
+
+	LogTopic(LogValue v0, LogValue v1 = {}, LogValue v2 = {}, LogValue v3 = {}, LogValue v4 = {}, LogValue v5 = {}, LogValue v6 = {}, LogValue v7 = {}, LogValue v8 = {}, LogValue v9 = {}) :
+		LogTopic(INFINITY, v0, v1, v2, v3, v4, v5, v6, v7, v8, v9) {};
 };

-const int logColumns = sizeof(logEntries) / sizeof(logEntries[0]);
-float logBuffer[LOG_SIZE][logColumns];
+LogTopic logTopics[] = {
+	// time
+	LogTopic({"t", &t}), // must be the first topic
+	LogTopic(1, {"loopRate", &loopRate}),

-void prepareLogData() {
-	attitudeEuler = attitude.toEuler();
-	attitudeTargetEuler = attitudeTarget.toEuler();
-}
+	// imu
+	LogTopic(
+		{"gyro.x", &gyro.x},
+		{"gyro.y", &gyro.y},
+		{"gyro.z", &gyro.z}),

-void logData() {
-	if (!armed) return;
-	static int logPointer = 0;
-	static Rate period(LOG_RATE);
-	if (!period) return;
+	LogTopic(50,
+		{"acc.x", &acc.x},
+		{"acc.y", &acc.y},
+		{"acc.z", &acc.z}),

-	prepareLogData();
+	LogTopic(10,
+		{"gyroBias.x", &gyroBias.x},
+		{"gyroBias.y", &gyroBias.y},
+		{"gyroBias.z", &gyroBias.z}),

-	for (int i = 0; i < logColumns; i++) {
-		logBuffer[logPointer][i] = *logEntries[i].value;
-	}
+	// estimation
+	LogTopic(50,
+		{"rates.x", &rates.x},
+		{"rates.y", &rates.y},
+		{"rates.z", &rates.z},
+		{"attitude.roll", []() { return attitude.getRoll(); }},
+		{"attitude.pitch", []() { return attitude.getPitch(); }},
+		{"attitude.yaw", []() { return attitude.getYaw(); }}),

-	logPointer++;
-	if (logPointer >= LOG_SIZE) {
-		logPointer = 0;
+	// rc
+	LogTopic(10,
+		{"controlTime", &controlTime, false}, // trigger value
+		{"controlRoll", &controlRoll},
+		{"controlPitch", &controlPitch},
+		{"controlYaw", &controlYaw},
+		{"controlThrottle", &controlThrottle}),
+
+	// control
+	LogTopic({"armed", &armed}),
+	LogTopic({"mode", &mode}),
+
+	LogTopic(10,
+		{"ratesTarget.x", &ratesTarget.x},
+		{"ratesTarget.y", &ratesTarget.y},
+		{"ratesTarget.z", &ratesTarget.z},
+		{"attitudeTarget.roll", []() { return attitudeTarget.getRoll(); }},
+		{"attitudeTarget.pitch", []() { return attitudeTarget.getPitch(); }},
+		{"attitudeTarget.yaw", []() { return attitudeTarget.getYaw(); }},
+		{"thrustTarget", &thrustTarget}),
+
+	// motors
+	LogTopic(
+		{"motors[0]", &motors[0]},
+		{"motors[1]", &motors[1]},
+		{"motors[2]", &motors[2]},
+		{"motors[3]", &motors[3]}),
+
+	// misc
+	LogTopic(5,
+		{"voltage", &voltage},
+		{"temp", &temperatureRead},
+		{"imuTemp", []() { return imu->getTemp(); }}),
+};
+
+void *logBuffer; // buffer for log data
+size_t logCapacity;
+size_t logCursor = 0;
+size_t logLength = 0;
+LogValue *logExposed = nullptr; // log values exposed to telemetry
+
+void setupLog() {
+	print("Setup log\n");
+
+	free(logBuffer); // when reconfiguring
+	logBuffer = nullptr;
+	logCursor = 0;
+	logLength = 0;
+
+	if (logMemory == 0) {
+		logCapacity = ESP.getFreeHeap() * logUsage;
+		logBuffer = (uint8_t *)calloc(logCapacity, 1);
+	} else if (logMemory == 1) {
+		logCapacity = ESP.getFreePsram() * logUsage;
+		logBuffer = (uint8_t *)heap_caps_calloc(logCapacity, 1, MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT);
 	}
 }

-void printLogHeader() {
-	for (int i = 0; i < logColumns; i++) {
-		print("%s%s", logEntries[i].name, i < logColumns - 1 ? "," : "\n");
-	}
-}
+void loopLog() {
+	if (logBuffer == nullptr || !armed) return;

-void printLogData() {
-	for (int i = 0; i < LOG_SIZE; i++) {
-		if (logBuffer[i][0] == 0) continue; // skip empty records
-		for (int j = 0; j < logColumns; j++) {
-			print("%g%s", logBuffer[i][j], j < logColumns - 1 ? "," : "\n");
+	if (!logLength) resetLog(); // reset state on first log write
+
+	static Rate sync(2);
+	if (sync) {
+		const uint8_t marker[] = {0x1A, 0x91, 0x4F, 0xF6, 0x7F};
+		writeLog(&marker, sizeof(marker)); // write sync marker
+	}
+
+	for (uint8_t i = 0; i < sizeof(logTopics) / sizeof(logTopics[0]); i++) {
+		LogTopic& topic = logTopics[i];
+		if (t - topic.lastUpdate < 1 / topic.throttle) continue; // throttle topic
+		if (!isTopicUpdated(i)) continue; // skip if topic was't updated
+
+		topic.lastUpdate = t;
+		writeLog(&i, sizeof(i)); // write topic index
+
+		for (auto& value : topic.values) {
+			if (value.name == nullptr) break;
+			if (!value.logged) continue;
+			value.lastValue = value.value.get();
+			writeLog(&value.lastValue, sizeof(float)); // write value
 		}
 	}
 }
+
+void resetLog() {
+	for (auto& topic : logTopics) {
+		topic.lastUpdate = -INFINITY;
+		for (auto& value : topic.values) {
+			value.lastValue = NAN;
+		}
+	}
+	logCursor = 0;
+	logLength = 0;
+}
+
+void writeLog(const void *data, size_t size) {
+	size_t first = min(size, logCapacity - logCursor);
+	size_t second = size - first;
+	memcpy(logBuffer + logCursor, data, first);
+	logCursor = (logCursor + first) % logCapacity;
+	if (second > 0) {
+		memcpy(logBuffer + logCursor, data + first, second);
+		logCursor = (logCursor + second) % logCapacity;
+	}
+	logLength = min(logLength + size, logCapacity);
+}
+
+void readLog(void *data, size_t position, size_t size) {
+	if (logLength == logCapacity) {
+		position = (logCursor + position) % logCapacity;
+	}
+	size_t first = min(size, logCapacity - position);
+	size_t second = size - first;
+	memcpy(data, logBuffer + position, first);
+	if (second > 0) {
+		memcpy(data + first, logBuffer, second);
+	}
+}
+
+bool isTopicUpdated(const uint8_t topic) {
+	LogTopic& logTopic = logTopics[topic];
+	bool updated = false;
+
+	for (auto& value : logTopic.values) {
+		if (value.name == nullptr) break;
+		float v = value.value.get();
+		if (!floatEquals(value.lastValue, v)) {
+			value.lastValue = v;
+			updated = true;
+		}
+	}
+	return updated;
+}
+
+void printLogInfo() {
+	if (logMemory == -1) return print("Log: disabled\n");
+
+	print("Memory: %s\n", logMemory == 0 ? "RAM" : "PSRAM");
+	print("Usage: %.f%%\n", logUsage * 100);
+	print("Capacity: %u bytes\n", (unsigned)logCapacity);
+	print("Used: %u bytes\n", (unsigned)logLength);
+	print("Estimated duration: %d seconds\n", estimateLogDuration());
+}
+
+int estimateLogDuration() {
+	float bandwidth = 0;
+	for (LogTopic& topic : logTopics) {
+		float rate = isinf(topic.throttle) ? loopRate : topic.throttle;
+		bandwidth += rate * topic.length * sizeof(float);
+	}
+	return logCapacity / bandwidth;
+}
+
+void printLogHeader() {
+	int i = 0;
+	for (auto& topic : logTopics) {
+		print("Topic #%d (%g Hz):\n", i++, topic.throttle);
+		for (auto& value : topic.values) {
+			if (value.name == nullptr) break;
+			print("  %s%s\n", value.name, value.logged ?"" : " (not logged)");
+		}
+	}
+}
+
+void printLogValues(const char *filter) {
+	for (LogTopic& topic : logTopics) {
+		for (LogValue& value : topic.values) {
+			if (value.name == nullptr) break;
+			if (strncasecmp(value.name, filter, strlen(filter))) continue;
+			print("%s = %g\n", value.name, value.value.get());
+		}
+	}
+}
+
+void configLogThrottle(const char *name, float throttle) {
+	for (LogTopic& topic : logTopics) {
+		for (LogValue& value : topic.values) {
+			if (value.name == nullptr) break;
+			if (strcasecmp(value.name, name) != 0) continue;
+			topic.throttle = throttle;
+			print("Log throttle for %s set to %.1f Hz\n", name, throttle);
+			return;
+		}
+	}
+	print("Log value not found: %s\n", name);
+}
+
+void exposeLogValue(const char *name) {
+	for (int i = 0; i < sizeof(logTopics) / sizeof(logTopics[0]); i++) {
+		LogTopic& topic = logTopics[i];
+		for (LogValue& value : topic.values) {
+			if (value.name == nullptr) break;
+			if (strcasecmp(value.name, name) != 0) continue;
+			logExposed = &value;
+			print("Log value %s exposed\n", name);
+			return;
+		}
+	}
+	print("Log value not found: %s\n", name);
+}
@@ -1,27 +0,0 @@
-// Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
-// Repository: https://github.com/okalachev/flix
-
-// Low pass filter implementation
-
-#pragma once
-
-template <typename T> // Using template to make the filter usable for scalar and vector values
-class LowPassFilter {
-public:
-	float alpha; // smoothing constant, 1 means filter disabled
-	T output;
-
-	LowPassFilter(float alpha): alpha(alpha) {};
-
-	T update(const T input) {
-		return output += alpha * (input - output);
-	}
-
-	void setCutOffFrequency(float cutOffFreq, float dt) {
-		alpha = 1 - exp(-2 * PI * cutOffFreq * dt);
-	}
-
-	void reset() {
-		output = T(); // set to zero
-	}
-};
@@ -7,12 +7,18 @@
 #include "util.h"

 extern float controlTime;
+extern float voltage;

 int mavlinkSysId = 1;
-Rate telemetryFast(10);
-Rate telemetrySlow(2);

-bool mavlinkConnected = false;
+Rate telemetrySlow(2);
+Rate telemetryAttitude(20);
+Rate telemetryRC(10);
+Rate telemetryMotors(10);
+Rate telemetryIMU(15);
+Rate telemetryTopic(10);
+
+float mavlinkTime = NAN; // time of last received message
 String mavlinkPrintBuffer;

 void processMavlink() {
@@ -33,35 +39,58 @@ void sendMavlink() {
 			((mode == AUTO) ? MAV_MODE_FLAG_AUTO_ENABLED : MAV_MODE_FLAG_MANUAL_INPUT_ENABLED),
 			mode, MAV_STATE_STANDBY);
 		sendMessage(&msg);
+	}

-		if (!mavlinkConnected) return; // send only heartbeat until connected
+	if (!valid(mavlinkTime)) return; // send only heartbeat until connected

+	if (telemetrySlow) {
 		mavlink_msg_extended_sys_state_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &msg,
 			MAV_VTOL_STATE_UNDEFINED, landed ? MAV_LANDED_STATE_ON_GROUND : MAV_LANDED_STATE_IN_AIR);
 		sendMessage(&msg);
 	}

-	if (telemetryFast && mavlinkConnected) {
+	if (telemetrySlow && valid(voltage)) {
+		uint16_t voltages[] = {(uint16_t)(voltage * 1000), UINT16_MAX, UINT16_MAX, UINT16_MAX, UINT16_MAX, UINT16_MAX, UINT16_MAX, UINT16_MAX, UINT16_MAX, UINT16_MAX};
+		uint16_t voltagesExt[] = {0, 0, 0, 0};
+		float remaining = constrain(mapf(voltage, 3.4, 4.2, 0, 1), 0, 1);
+		mavlink_msg_battery_status_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &msg, 0, MAV_BATTERY_FUNCTION_ALL,
+			MAV_BATTERY_TYPE_LIPO, INT16_MAX, voltages, -1, -1, -1, remaining * 100, 0, MAV_BATTERY_CHARGE_STATE_OK, voltagesExt, 0, 0);
+		sendMessage(&msg);
+	}
+
+	if (telemetryAttitude) {
 		const float offset[] = {0, 0, 0, 0};
 		mavlink_msg_attitude_quaternion_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &msg,
 			time, attitude.w, attitude.x, -attitude.y, -attitude.z, rates.x, -rates.y, -rates.z, offset); // convert to frd
 		sendMessage(&msg);
+	}

+	if (telemetryRC && channels[0]) { // 0 means no RC input
 		mavlink_msg_rc_channels_raw_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &msg, controlTime * 1000, 0,
 			channels[0], channels[1], channels[2], channels[3], channels[4], channels[5], channels[6], channels[7], UINT8_MAX);
-		if (channels[0] != 0) sendMessage(&msg); // 0 means no RC input
+		sendMessage(&msg);
+	}

+	if (telemetryMotors) {
 		float controls[8];
 		memcpy(controls, motors, sizeof(motors));
 		mavlink_msg_actuator_control_target_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &msg, time, 0, controls);
 		sendMessage(&msg);
+	}

+	if (telemetryIMU) {
 		mavlink_msg_scaled_imu_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &msg, time,
-			acc.x * 1000, -acc.y * 1000, -acc.z * 1000, // convert to frd
+			acc.x / ONE_G * 1000, -acc.y / ONE_G * 1000, -acc.z / ONE_G * 1000, // convert to frd
 			gyro.x * 1000, -gyro.y * 1000, -gyro.z * 1000,
 			0, 0, 0, 0);
 		sendMessage(&msg);
 	}
+
+	if (telemetryTopic && logExposed != nullptr) {
+		mavlink_msg_named_value_float_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &msg,
+			time, logExposed->name, logExposed->value.get());
+		sendMessage(&msg);
+	}
 }

 void sendMessage(const void *msg) {
@@ -70,16 +99,36 @@ void sendMessage(const void *msg) {
 	sendWiFi(buf, len);
 }

+static uint8_t mavlinkBatch[ESP_NOW_MAX_DATA_LEN_V2];
+static int mavlinkBatchSize = 0;
+
+void batchMessage(const void *msg) {
+	uint8_t buf[MAVLINK_MAX_PACKET_LEN];
+	int len = mavlink_msg_to_send_buffer(buf, (mavlink_message_t *)msg);
+
+	if (mavlinkBatchSize + len > sizeof(mavlinkBatch)) {
+		sendWiFi(mavlinkBatch, mavlinkBatchSize);
+		mavlinkBatchSize = 0;
+	}
+	memcpy(mavlinkBatch + mavlinkBatchSize, buf, len);
+	mavlinkBatchSize += len;
+}
+
+void flushBatchMessages() {
+	sendWiFi(mavlinkBatch, mavlinkBatchSize);
+	mavlinkBatchSize = 0;
+}
+
 void receiveMavlink() {
 	uint8_t buf[MAVLINK_MAX_PACKET_LEN];
 	int len = receiveWiFi(buf, MAVLINK_MAX_PACKET_LEN);
-	if (len) mavlinkConnected = true;

 	// New packet, parse it
 	mavlink_message_t msg;
 	mavlink_status_t status;
 	for (int i = 0; i < len; i++) {
 		if (mavlink_parse_char(MAVLINK_COMM_0, buf[i], &msg, &status)) {
+			mavlinkTime = t;
 			handleMavlink(&msg);
 		}
 	}
@@ -174,18 +223,24 @@ void handleMavlink(const void *_msg) {
 		mavlink_msg_set_attitude_target_decode(&msg, &m);
 		if (m.target_system && m.target_system != mavlinkSysId) return;

-		// copy attitude, rates and thrust targets
-		ratesTarget.x = m.body_roll_rate;
-		ratesTarget.y = -m.body_pitch_rate; // convert to flu
-		ratesTarget.z = -m.body_yaw_rate;
-		attitudeTarget.w = m.q[0];
-		attitudeTarget.x = m.q[1];
-		attitudeTarget.y = -m.q[2];
-		attitudeTarget.z = -m.q[3];
-		thrustTarget = m.thrust;
-		ratesExtra = Vector(0, 0, 0);
+		if (!(m.type_mask & ATTITUDE_TARGET_TYPEMASK_ATTITUDE_IGNORE)) {
+			// Attitude control
+			attitudeTarget.w = m.q[0];
+			attitudeTarget.x = m.q[1];
+			attitudeTarget.y = -m.q[2]; // convert to flu
+			attitudeTarget.z = -m.q[3];
+			ratesExtra.x = m.body_roll_rate;
+			ratesExtra.y = -m.body_pitch_rate;
+			ratesExtra.z = -m.body_yaw_rate;
+		} else {
+			// Rates control
+			attitudeTarget.invalidate();
+			ratesTarget.x = m.body_roll_rate;
+			ratesTarget.y = -m.body_pitch_rate;
+			ratesTarget.z = -m.body_yaw_rate;
+		}

-		if (m.type_mask & ATTITUDE_TARGET_TYPEMASK_ATTITUDE_IGNORE) attitudeTarget.invalidate();
+		thrustTarget = valid(m.thrust) ? m.thrust : thrustTarget;
 		armed = m.thrust > 0;
 	}

@@ -203,18 +258,29 @@ void handleMavlink(const void *_msg) {
 		armed = motors[0] > 0 || motors[1] > 0 || motors[2] > 0 || motors[3] > 0;
 	}

+	if (msg.msgid == MAVLINK_MSG_ID_LOG_REQUEST_LIST) {
+		const uint32_t qgcEpoch = 1262304000; // qgc accepts only timestamps after 2010-01-01
+		mavlink_message_t response;
+		mavlink_msg_log_entry_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &response,
+			0, 1, 0, qgcEpoch + t * 60, logLength); // put fake unique date to make qgc happy with saving logs
+		sendMessage(&response);
+	}
+
 	if (msg.msgid == MAVLINK_MSG_ID_LOG_REQUEST_DATA) {
 		mavlink_log_request_data_t m;
 		mavlink_msg_log_request_data_decode(&msg, &m);
 		if (m.target_system && m.target_system != mavlinkSysId) return;

-		// Send all log records
-		for (int i = 0; i < sizeof(logBuffer) / sizeof(logBuffer[0]); i++) {
-			mavlink_message_t msg;
-			mavlink_msg_log_data_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &msg, 0, i,
-				sizeof(logBuffer[0]), (uint8_t *)logBuffer[i]);
-			sendMessage(&msg);
+		for (int i = 0; i < m.count; i += MAVLINK_MSG_LOG_DATA_FIELD_DATA_LEN) {
+			int chunkSize = min(MAVLINK_MSG_LOG_DATA_FIELD_DATA_LEN, (int)(m.count - i));
+			mavlink_message_t response;
+			uint8_t data[MAVLINK_MSG_LOG_DATA_FIELD_DATA_LEN];
+			readLog(data, m.ofs + i, chunkSize);
+			mavlink_msg_log_data_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &response,
+				m.id, m.ofs + i, chunkSize, data);
+			batchMessage(&response);
 		}
+		flushBatchMessages();
 	}

 	// Handle commands
@@ -233,7 +299,7 @@ void handleMavlink(const void *_msg) {
 		}

 		if (m.command == MAV_CMD_COMPONENT_ARM_DISARM) {
-			if (m.param1 && controlThrottle > 0.05) return; // don't arm if throttle is not low
+			if (m.param1 == 1 && controlThrottle > 0.05) return; // don't arm if throttle is not low
 			accepted = true;
 			armed = m.param1 == 1;
 		}
@@ -7,37 +7,36 @@

 float motors[4]; // normalized motor thrusts in range [0..1]

-int motorPins[4] = {12, 13, 14, 15}; // default pin numbers
+int motorPins[4] = {-1, -1, -1, -1}; // default pin numbers
 int pwmFrequency = 78000;
 int pwmResolution = 10;
 int pwmStop = 0;
 int pwmMin = 0;
 int pwmMax = -1; // -1 means duty cycle mode

-const int MOTOR_REAR_LEFT = 0;
-const int MOTOR_REAR_RIGHT = 1;
-const int MOTOR_FRONT_RIGHT = 2;
-const int MOTOR_FRONT_LEFT = 3;
+const int MOTOR_REAR_LEFT = 0, MOTOR_REAR_RIGHT = 1, MOTOR_FRONT_RIGHT = 2, MOTOR_FRONT_LEFT = 3;

 void setupMotors() {
-	print("Setup Motors\n");
-	// configure pins
+	print("Setup motors\n");
+	// Configure pins
 	for (int i = 0; i < 4; i++) {
+		if (motorPins[i] < 0) continue; // skip unassigned motors
 		ledcAttach(motorPins[i], pwmFrequency, pwmResolution);
 		pwmFrequency = ledcChangeFrequency(motorPins[i], pwmFrequency, pwmResolution); // when reconfiguring
 	}
 	sendMotors();
-	print("Motors initialized\n");
 }

 void sendMotors() {
 	for (int i = 0; i < 4; i++) {
+		if (motorPins[i] < 0) continue; // skip unassigned motors
 		ledcWrite(motorPins[i], getDutyCycle(motors[i]));
 	}
 }

 int getDutyCycle(float value) {
 	value = constrain(value, 0, 1);
+
 	if (pwmMax >= 0) { // pwm mode
 		float pwm = mapf(value, 0, 1, pwmMin, pwmMax);
 		if (value == 0) pwm = pwmStop;
@@ -52,9 +51,9 @@ bool motorsActive() {
 	return motors[0] != 0 || motors[1] != 0 || motors[2] != 0 || motors[3] != 0;
 }

-void testMotor(int n) {
+void testMotor(int n, float thrust) {
 	print("Testing motor %d\n", n);
-	motors[n] = 1;
+	motors[n] = thrust;
 	delay(50); // ESP32 may need to wait until the end of the current cycle to change duty https://github.com/espressif/arduino-esp32/issues/5306
 	sendMotors();
 	pause(3);
@@ -6,25 +6,25 @@
 #include <Preferences.h>
 #include "util.h"

-extern int channelZero[16];
-extern int channelMax[16];
+extern int channelZero[16], channelMax[16];
 extern int rollChannel, pitchChannel, throttleChannel, yawChannel, armedChannel, modeChannel;
-extern int rcRxPin;
-extern int wifiMode, udpLocalPort, udpRemotePort;
-extern float rcLossTimeout, descendTime;
+extern int rcRxPin, voltagePin;
+extern int wifiMode, wifiLongRange, wifiBroadcast, udpLocalPort, udpRemotePort, espnowChannel;
+extern float rcLossTimeout, descendTime, disarmTilt;
+extern float voltageScale;
+extern LowPassFilter<float> voltageFilter;
+
+#include "config.h"

 Preferences storage;

 struct Parameter {
 	const char *name; // max length is 15
-	bool integer;
-	union { float *f; int *i; }; // pointer to the variable
+	Value value; // pointer to the variable
+	float initial; // default value
 	float cache; // what's stored in flash
 	void (*callback)(); // called after parameter change
-	Parameter(const char *name, float *variable, void (*callback)() = nullptr) : name(name), integer(false), f(variable), callback(callback) {};
-	Parameter(const char *name, int *variable, void (*callback)() = nullptr) : name(name), integer(true), i(variable), callback(callback) {};
-	float getValue() const { return integer ? *i : *f; };
-	void setValue(const float value) { if (integer) *i = value; else *f = value; };
+	Parameter(const char *name, Value value, void (*callback)() = nullptr) : name(name), value(value), callback(callback) {};
 };

 Parameter parameters[] = {
@@ -33,13 +33,17 @@ Parameter parameters[] = {
 	{"CTL_R_RATE_I", &rollRatePID.i},
 	{"CTL_R_RATE_D", &rollRatePID.d},
 	{"CTL_R_RATE_WU", &rollRatePID.windup},
+	{"CTL_R_RATE_D_A", &rollRatePID.lpf.alpha},
 	{"CTL_P_RATE_P", &pitchRatePID.p},
 	{"CTL_P_RATE_I", &pitchRatePID.i},
 	{"CTL_P_RATE_D", &pitchRatePID.d},
 	{"CTL_P_RATE_WU", &pitchRatePID.windup},
+	{"CTL_P_RATE_D_A", &pitchRatePID.lpf.alpha},
 	{"CTL_Y_RATE_P", &yawRatePID.p},
 	{"CTL_Y_RATE_I", &yawRatePID.i},
 	{"CTL_Y_RATE_D", &yawRatePID.d},
+	{"CTL_Y_RATE_WU", &yawRatePID.windup},
+	{"CTL_Y_RATE_D_A", &yawRatePID.lpf.alpha},
 	{"CTL_R_P", &rollPID.p},
 	{"CTL_R_I", &rollPID.i},
 	{"CTL_R_D", &rollPID.d},
@@ -55,6 +59,15 @@ Parameter parameters[] = {
 	{"CTL_FLT_MODE_1", &flightModes[1]},
 	{"CTL_FLT_MODE_2", &flightModes[2]},
 	// imu
+	{"IMU_MODEL", &imuModel},
+	{"IMU_BUS", &imuBus},
+	{"IMU_PIN_SCK", &imuSckPin},
+	{"IMU_PIN_MISO", &imuMisoPin},
+	{"IMU_PIN_MOSI", &imuMosiPin},
+	{"IMU_PIN_CS", &imuCsPin},
+	{"IMU_PIN_SDA", &imuSdaPin},
+	{"IMU_PIN_SCL", &imuSclPin},
+	{"IMU_PIN_INT", &imuIntPin},
 	{"IMU_ROT_ROLL", &imuRotation.x},
 	{"IMU_ROT_PITCH", &imuRotation.y},
 	{"IMU_ROT_YAW", &imuRotation.z},
@@ -67,7 +80,10 @@ Parameter parameters[] = {
 	{"IMU_GYRO_BIAS_A", &gyroBiasFilter.alpha},
 	// estimate
 	{"EST_ACC_WEIGHT", &accWeight},
+	{"EST_LVL_WEIGHT", &levelWeight},
 	{"EST_RATES_LPF_A", &ratesFilter.alpha},
+	{"EST_RATES_NF_F", &ratesNotch.frequency, setupEstimate},
+	{"EST_RATES_NF_BW", &ratesNotch.bandwidth, setupEstimate},
 	// motors
 	{"MOT_PIN_FL", &motorPins[MOTOR_FRONT_LEFT], setupMotors},
 	{"MOT_PIN_FR", &motorPins[MOTOR_FRONT_RIGHT], setupMotors},
@@ -79,7 +95,7 @@ Parameter parameters[] = {
 	{"MOT_PWM_MIN", &pwmMin},
 	{"MOT_PWM_MAX", &pwmMax},
 	// rc
-	{"RC_RX_PIN", &rcRxPin},
+	{"RC_RX_PIN", &rcRxPin, setupRC},
 	{"RC_ZERO_0", &channelZero[0]},
 	{"RC_ZERO_1", &channelZero[1]},
 	{"RC_ZERO_2", &channelZero[2]},
@@ -103,27 +119,56 @@ Parameter parameters[] = {
 	{"RC_MODE", &modeChannel},
 	// wifi
 	{"WIFI_MODE", &wifiMode},
-	{"WIFI_LOC_PORT", &udpLocalPort},
-	{"WIFI_REM_PORT", &udpRemotePort},
+	{"WIFI_PORT_LOC", &udpLocalPort},
+	{"WIFI_PORT_REM", &udpRemotePort},
+	{"WIFI_LONG_RANGE", &wifiLongRange},
+	{"WIFI_BROADCAST", &wifiBroadcast},
+	// espnow
+	{"ESPNOW_CHANNEL", &espnowChannel},
 	// mavlink
 	{"MAV_SYS_ID", &mavlinkSysId},
 	{"MAV_RATE_SLOW", &telemetrySlow.rate},
-	{"MAV_RATE_FAST", &telemetryFast.rate},
+	{"MAV_RATE_ATT", &telemetryAttitude.rate},
+	{"MAV_RATE_RC", &telemetryRC.rate},
+	{"MAV_RATE_MOT", &telemetryMotors.rate},
+	{"MAV_RATE_IMU", &telemetryIMU.rate},
+	{"MAV_RATE_TOPIC", &telemetryTopic.rate},
+	// log
+	{"LOG_MEMORY", &logMemory, setupLog},
+	{"LOG_USAGE", &logUsage, setupLog},
+	{"LOG_RATE_000", &logTopics[0].throttle},
+	{"LOG_RATE_001", &logTopics[1].throttle},
+	{"LOG_RATE_002", &logTopics[2].throttle},
+	{"LOG_RATE_003", &logTopics[3].throttle},
+	{"LOG_RATE_004", &logTopics[4].throttle},
+	{"LOG_RATE_005", &logTopics[5].throttle},
+	{"LOG_RATE_006", &logTopics[6].throttle},
+	{"LOG_RATE_007", &logTopics[7].throttle},
+	{"LOG_RATE_008", &logTopics[8].throttle},
+	{"LOG_RATE_009", &logTopics[9].throttle},
+	{"LOG_RATE_010", &logTopics[10].throttle},
+	{"LOG_RATE_011", &logTopics[11].throttle},
+	// power
+	{"PWR_VOLT_PIN", &voltagePin, setupPower},
+	{"PWR_VOLT_SCALE", &voltageScale},
+	{"PWR_VOLT_LPF_A", &voltageFilter.alpha},
 	// safety
 	{"SF_RC_LOSS_TIME", &rcLossTimeout},
 	{"SF_DESCEND_TIME", &descendTime},
+	{"SF_DISARM_TILT", &disarmTilt},
 };

 void setupParameters() {
 	print("Setup parameters\n");
+	setDefaults();
 	storage.begin("flix");
 	// Read parameters from storage
 	for (auto &parameter : parameters) {
-		if (!storage.isKey(parameter.name)) {
-			storage.putFloat(parameter.name, parameter.getValue()); // store default value
+		parameter.initial = parameter.value.get();
+		if (storage.isKey(parameter.name)) {
+			parameter.value.set(storage.getFloat(parameter.name));
 		}
-		parameter.setValue(storage.getFloat(parameter.name, 0));
-		parameter.cache = parameter.getValue();
+		parameter.cache = parameter.value.get();
 	}
 }

@@ -138,13 +183,13 @@ const char *getParameterName(int index) {

 float getParameter(int index) {
 	if (index < 0 || index >= parametersCount()) return NAN;
-	return parameters[index].getValue();
+	return parameters[index].value.get();
 }

 float getParameter(const char *name) {
 	for (auto &parameter : parameters) {
 		if (strcasecmp(parameter.name, name) == 0) {
-			return parameter.getValue();
+			return parameter.value.get();
 		}
 	}
 	return NAN;
@@ -153,10 +198,9 @@ float getParameter(const char *name) {
 bool setParameter(const char *name, const float value) {
 	for (auto &parameter : parameters) {
 		if (strcasecmp(parameter.name, name) == 0) {
-			if (parameter.integer && !isfinite(value)) return false; // can't set integer to NaN or Inf
-			parameter.setValue(value);
+			bool success = parameter.value.set(value);
 			if (parameter.callback) parameter.callback();
-			return true;
+			return success;
 		}
 	}
 	return false;
@@ -168,17 +212,23 @@ void syncParameters() {
 	if (motorsActive()) return; // don't use flash while flying, it may cause a delay

 	for (auto &parameter : parameters) {
-		if (parameter.getValue() == parameter.cache) continue; // no change
-		if (isnan(parameter.getValue()) && isnan(parameter.cache)) continue; // both are NAN
+		if (floatEquals(parameter.value.get(), parameter.cache)) continue; // no change

-		storage.putFloat(parameter.name, parameter.getValue());
-		parameter.cache = parameter.getValue(); // update cache
+		storage.putFloat(parameter.name, parameter.value.get());
+		parameter.cache = parameter.value.get(); // update cache
 	}
 }

-void printParameters() {
+void printParameters(const char *filter) {
+	print("Name             Value          [Default]\n");
 	for (auto &parameter : parameters) {
-		print("%s = %g\n", parameter.name, parameter.getValue());
+		if (strncasecmp(parameter.name, filter, strlen(filter))) continue;
+
+		if (floatEquals(parameter.value.get(), parameter.initial)) { // parameter changed
+			print("%-15s  %-13g\n", parameter.name, parameter.value.get());
+		} else {
+			print("%-15s  %-13g  [%g]\n", parameter.name, parameter.value.get(), parameter.initial);
+		}
 	}
 }

@@ -5,7 +5,7 @@

 #pragma once

-#include "lpf.h"
+#include "filter.h"

 class PID {
 public:
@@ -18,7 +18,7 @@ public:

 	LowPassFilter<float> lpf; // low pass filter for derivative term

-	PID(float p, float i, float d, float windup = 0, float dAlpha = 1, float dtMax = 0.1) :
+	PID(float p, float i = 0, float d = 0, float windup = INFINITY, float dAlpha = 1, float dtMax = 0.1) :
 		p(p), i(i), d(d), windup(windup), lpf(dAlpha), dtMax(dtMax) {}

 	float update(float error) {
@@ -0,0 +1,29 @@
+// Copyright (c) 2026 Oleg Kalachev <okalachev@gmail.com>
+// Repository: https://github.com/okalachev/flix
+
+// Power management
+
+#include <soc/soc.h>
+#include <soc/rtc_cntl_reg.h>
+#include "filter.h"
+#include "util.h"
+
+float voltage = NAN;
+LowPassFilter<float> voltageFilter(1);
+int voltagePin = -1;
+float voltageScale = 2;
+
+void setupPower() {
+	REG_CLR_BIT(RTC_CNTL_BROWN_OUT_REG, RTC_CNTL_BROWN_OUT_ENA); // disable reset on low voltage
+	if (digitalPinToAnalogChannel(voltagePin) == -1) voltagePin = -1; // test ADC pin
+}
+
+void readVoltage() {
+	if (voltagePin < 0) return;
+
+	static Rate rate(10);
+	if (!rate) return;
+
+	float v = analogReadMilliVolts(voltagePin) * voltageScale / 1000.0f;
+	voltage = voltageFilter.update(v);
+}
@@ -6,7 +6,7 @@
 #include <SBUS.h>
 #include "util.h"

-SBUS rc(Serial2);
+SBUS rc(Serial1);
 int rcRxPin = -1; // -1 means disabled

 uint16_t channels[16]; // raw rc channels
@@ -27,14 +27,12 @@ void setupRC() {

 bool readRC() {
 	if (rcRxPin < 0) return false;
-	if (rc.read()) {
-		SBUSData data = rc.data();
-		for (int i = 0; i < 16; i++) channels[i] = data.ch[i]; // copy channels data
-		normalizeRC();
-		controlTime = t;
-		return true;
-	}
-	return false;
+	if (!rc.read()) return false;
+
+	rc.getChannels(channels);
+	normalizeRC();
+	controlTime = t;
+	return true;
 }

 void normalizeRC() {
@@ -55,18 +53,19 @@ void calibrateRC() {
 		print("RC_RX_PIN = %d, set the RC pin!\n", rcRxPin);
 		return;
 	}
-	uint16_t zero[16];
-	uint16_t center[16];
-	uint16_t max[16];
+
+	uint16_t zero[16]; // for zero positions
+	uint16_t center[16]; // for center positions
+	uint16_t _[16]; // for unused data
 	print("1/8 Calibrating RC: put all switches to default positions [3 sec]\n");
 	pause(3);
-	calibrateRCChannel(NULL, zero, zero, "2/8 Move sticks [3 sec]\n...     ...\n...     .o.\n.o.     ...\n");
-	calibrateRCChannel(NULL, center, center, "3/8 Move sticks [3 sec]\n...     ...\n.o.     .o.\n...     ...\n");
-	calibrateRCChannel(&throttleChannel, zero, max, "4/8 Move sticks [3 sec]\n.o.     ...\n...     .o.\n...     ...\n");
-	calibrateRCChannel(&yawChannel, center, max, "5/8 Move sticks [3 sec]\n...     ...\n..o     .o.\n...     ...\n");
-	calibrateRCChannel(&pitchChannel, zero, max, "6/8 Move sticks [3 sec]\n...     .o.\n...     ...\n.o.     ...\n");
-	calibrateRCChannel(&rollChannel, zero, max, "7/8 Move sticks [3 sec]\n...     ...\n...     ..o\n.o.     ...\n");
-	calibrateRCChannel(&modeChannel, zero, max, "8/8 Put mode switch to max [3 sec]\n");
+	calibrateRCChannel(NULL, _, zero, "2/8 Move sticks [3 sec]\n...     ...\n...     .o.\n.o.     ...\n");
+	calibrateRCChannel(&throttleChannel, zero, _, "3/8 Move sticks [3 sec]\n.o.     ...\n...     .o.\n...     ...\n");
+	calibrateRCChannel(NULL, _, center, "4/8 Move sticks [3 sec]\n...     ...\n.o.     .o.\n...     ...\n");
+	calibrateRCChannel(&yawChannel, center, _, "5/8 Move sticks [3 sec]\n...     ...\n..o     .o.\n...     ...\n");
+	calibrateRCChannel(&pitchChannel, zero, _, "6/8 Move sticks [3 sec]\n...     .o.\n...     ...\n.o.     ...\n");
+	calibrateRCChannel(&rollChannel, zero, _, "7/8 Move sticks [3 sec]\n...     ...\n...     ..o\n.o.     ...\n");
+	calibrateRCChannel(&modeChannel, zero, _, "8/8 Put mode switch to max [3 sec]\n");
 	printRCCalibration();
 }

@@ -8,10 +8,12 @@ extern float controlRoll, controlPitch, controlThrottle, controlYaw;

 float rcLossTimeout = 1;
 float descendTime = 10;
+float disarmTilt = radians(120);

 void failsafe() {
 	rcLossFailsafe();
 	autoFailsafe();
+	tiltFailsafe();
 }

 // RC loss failsafe
@@ -36,12 +38,24 @@ void descend() {
 // Allow pilot to interrupt automatic flight
 void autoFailsafe() {
 	static float roll, pitch, yaw, throttle;
-	if (roll != controlRoll || pitch != controlPitch || yaw != controlYaw || abs(throttle - controlThrottle) > 0.05) {
-		// controls changed
-		if (mode == AUTO) mode = STAB; // regain control by the pilot
+	if (abs(roll - controlRoll) > 0.05 || abs(pitch - controlPitch) > 0.05 || abs(yaw - controlYaw) > 0.05 || abs(throttle - controlThrottle) > 0.05) {
+		// controls changed and mode switch is not configured
+		if (mode == AUTO && invalid(controlMode)) mode = STAB; // regain control by the pilot
 	}
 	roll = controlRoll;
 	pitch = controlPitch;
 	yaw = controlYaw;
 	throttle = controlThrottle;
 }
+
+// Disarm if tilted too much
+void tiltFailsafe() {
+	if (!armed) return;
+	if (mode != STAB) return;
+
+	Vector up = Quaternion::rotateVector(Vector(0, 0, 1), attitude);
+	float tilt = acos(up.z);
+	if (disarmTilt && tilt > disarmTilt) {
+		armed = false;
+	}
+}
@@ -6,12 +6,13 @@
 #pragma once

 #include <math.h>
-#include <soc/soc.h>
-#include <soc/rtc_cntl_reg.h>
+#include <ESP32_NOW_Serial.h>

 const float ONE_G = 9.80665;
 extern float t;

+#define STRINGIFY(x) __STRINGIFY(x)
+
 float mapf(float x, float in_min, float in_max, float out_min, float out_max) {
 	return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
 }
@@ -24,6 +25,12 @@ bool valid(float x) {
 	return isfinite(x);
 }

+bool floatEquals(float a, float b, float epsilon = 0) {
+	if (isnan(a) && isnan(b)) return true;
+	if (a == b) return true;
+	return fabsf(a - b) <= epsilon;
+}
+
 // Wrap angle to [-PI, PI)
 float wrapAngle(float angle) {
 	angle = fmodf(angle, 2 * PI);
@@ -35,29 +42,85 @@ float wrapAngle(float angle) {
 	return angle;
 }

-// Disable reset on low voltage
-void disableBrownOut() {
-	REG_CLR_BIT(RTC_CNTL_BROWN_OUT_REG, RTC_CNTL_BROWN_OUT_ENA);
-}
-
 // Trim and split string by spaces
 void splitString(String& str, String& token0, String& token1, String& token2) {
 	str.trim();
+	if (str.isEmpty()) return;
 	char chars[str.length() + 1];
 	str.toCharArray(chars, str.length() + 1);
 	token0 = strtok(chars, " ");
-	token1 = strtok(NULL, " "); // String(NULL) creates empty string
+	token1 = strtok(NULL, " ");
 	token2 = strtok(NULL, "");
+	if (token1.c_str() == NULL) token1 = "";
+	if (token2.c_str() == NULL) token2 = "";
 }

+// Simplified ESP-NOW Serial without resends
+class ESPNOWSerial : public ESP_NOW_Serial_Class {
+public:
+	int lost = 0;
+	using ESP_NOW_Serial_Class::ESP_NOW_Serial_Class;
+	void onSent(bool success) override {
+		if (!success) lost++;
+		ESP_NOW_Serial_Class::onSent(true); // always report success to avoid resends
+	}
+};
+
+// Simple variant type for logging and parameters
+struct Value {
+	enum { EMPTY, FLOAT, INT, BOOL, FLOAT_FN, INT_FN, BOOL_FN } type;
+	union {
+		void *pointer;
+		float *_float;
+		int *_int;
+		bool *_bool;
+		float (*floatFn)();
+		int (*intFn)();
+		bool (*boolFn)();
+	};
+
+	Value() : type(EMPTY), pointer(nullptr) {};
+	Value(float *pt) : type(FLOAT), _float(pt) {};
+	Value(int *pt) : type(INT), _int(pt) {};
+	Value(bool *pt) : type(BOOL), _bool(pt) {};
+	Value(float (*fn)()) : type(FLOAT_FN), floatFn(fn) {};
+	Value(int (*fn)()) : type(INT_FN), intFn(fn) {};
+	Value(bool (*fn)()) : type(BOOL_FN), boolFn(fn) {};
+
+	float get() const {
+		switch (type) {
+			case FLOAT: return *_float;
+			case INT: return *_int;
+			case BOOL: return *_bool ? 1 : 0;
+			case FLOAT_FN: return floatFn();
+			case INT_FN: return intFn();
+			case BOOL_FN: return boolFn() ? 1 : 0;
+			default: return NAN;
+		}
+	};
+
+	bool set(float value) const {
+		switch (type) {
+			case FLOAT: *_float = value; break;
+			case INT: if (!isfinite(value)) return false; *_int = value; break;
+			case BOOL: *_bool = (value != 0); break;
+			default: return false;
+		}
+		return true;
+	}
+};
+
 // Rate limiter
 class Rate {
 public:
 	float rate;
-	float last = 0;
+	float last = -INFINITY;
 	Rate(float rate) : rate(rate) {}

 	operator bool() {
+		if (t == last) {
+			return true; // the same step
+		}
 		if (t - last >= 1 / rate) {
 			last = t;
 			return true;
@@ -105,10 +105,23 @@ public:
 	}

 	static Vector rotationVectorBetween(const Vector& a, const Vector& b) {
+		float an = a.norm();
+		float bn = b.norm();
+		if (an < 1e-6 || bn < 1e-6) {
+			return Vector(0, 0, 0);
+		}
 		Vector direction = cross(a, b);
-		if (direction.zero()) {
-			// vectors are opposite, return any perpendicular vector
-			return cross(a, Vector(1, 0, 0));
+		if (direction.norm() < 1e-6) { // vectors are parallel
+			if (dot(a, b) > 0) { // same direction
+				return Vector(0, 0, 0);
+			}
+			// opposite direction
+			Vector perp = cross(a, Vector(1, 0, 0));
+			if (perp.norm() < 1e-6) {
+				perp = cross(a, Vector(0, 1, 0));
+			}
+			perp.normalize();
+			return perp * PI;
 		}
 		direction.normalize();
 		float angle = angleBetween(a, b);
@@ -1,76 +1,154 @@
 // Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
 // Repository: https://github.com/okalachev/flix

-// Wi-Fi communication
+// Wi-Fi and ESP-NOW communication

 #include <WiFi.h>
 #include <WiFiAP.h>
 #include <WiFiUdp.h>
-#include "Preferences.h"
+#include <MacAddress.h>
+#include <ESP32_NOW_Serial.h>
+#include <Preferences.h>
+#include "util.h"

 extern Preferences storage; // use the main preferences storage

-const int W_DISABLED = 0, W_AP = 1, W_STA = 2;
+const int W_DISABLED = 0, W_AP = 1, W_STA = 2, W_ESPNOW = 3;
 int wifiMode = W_AP;
+
+int wifiLongRange = 0;
+int wifiBroadcast = 0; // 0 - broadcast until connected, 1 - always broadcast
 int udpLocalPort = 14550;
 int udpRemotePort = 14550;
 IPAddress udpRemoteIP = "255.255.255.255";
-
 WiFiUDP udp;

+ESPNOWSerial espnow(NULL, 0, WIFI_IF_AP);
+ESPNOWSerial espnowBroadcast(ESP_NOW.BROADCAST_ADDR, 0, WIFI_IF_AP);
+int espnowChannel = 6;
+
 void setupWiFi() {
 	print("Setup Wi-Fi\n");
+	WiFi.enableLongRange(wifiLongRange);
+
 	if (wifiMode == W_AP) {
 		WiFi.softAP(storage.getString("WIFI_AP_SSID", "flix").c_str(), storage.getString("WIFI_AP_PASS", "flixwifi").c_str());
-	} else if (wifiMode == W_STA) {
-		WiFi.begin(storage.getString("WIFI_STA_SSID", "").c_str(), storage.getString("WIFI_STA_PASS", "").c_str());
+		udp.begin(udpLocalPort);
 	}
-	udp.begin(udpLocalPort);
+
+	if (wifiMode == W_STA) {
+		WiFi.begin(storage.getString("WIFI_STA_SSID", "").c_str(), storage.getString("WIFI_STA_PASS", "").c_str());
+		udp.begin(udpLocalPort);
+	}
+
+	if (wifiMode == W_ESPNOW) {
+		WiFi.mode(WIFI_AP);
+		WiFi.setChannel(espnowChannel);
+		espnow.addr(MacAddress(storage.getString("ESPNOW_PEER_MAC", "FF:FF:FF:FF:FF:FF").c_str()));
+		String key = storage.getString("ESPNOW_PEER_KEY", "");
+		espnow.setKey(key.isEmpty() ? nullptr : (const uint8_t *)key.c_str());
+		espnow.begin();
+		espnowBroadcast.begin();
+	}
+
+	WiFi.setSleep(false); // disable power save
 }

 void sendWiFi(const uint8_t *buf, int len) {
+	if (espnow) {
+		espnow.write(buf, len);
+
+		static Rate discovery(2);
+		if (espnow.isEncrypted() && discovery) espnowBroadcast.write((const uint8_t *)"flix", 4); // broadcast message to help finding this device
+		return;
+	}
+
 	if (WiFi.softAPgetStationNum() == 0 && !WiFi.isConnected()) return;
-	udp.beginPacket(udpRemoteIP, udpRemotePort);
+
+	bool broadcast = wifiBroadcast || !(t - mavlinkTime < 5); // broadcast if lost connection
+	udp.beginPacket(broadcast ? IPAddress(255, 255, 255, 255) : udpRemoteIP, udpRemotePort);
 	udp.write(buf, len);
 	udp.endPacket();
 }

 int receiveWiFi(uint8_t *buf, int len) {
+	if (espnow) {
+		return espnow.read(buf, len);
+	}
+
+	if (WiFi.softAPgetStationNum() == 0 && !WiFi.isConnected()) return 0;
+
 	udp.parsePacket();
 	if (udp.remoteIP()) udpRemoteIP = udp.remoteIP();
 	return udp.read(buf, len);
 }

 void printWiFiInfo() {
-	if (WiFi.getMode() == WIFI_MODE_AP) {
+	if (espnow) {
+		print("Mode: ESP-NOW\n");
+		print("ESP-NOW version: %d\n", ESP_NOW.getVersion());
+		print("Max packet size: %d\n", ESP_NOW.getMaxDataLen());
+		print("MAC: %s\n", WiFi.softAPmacAddress().c_str());
+		print("Peer MAC: %s\n", MacAddress(espnow.addr()).toString().c_str());
+		print("Encrypted: %d\n", espnow.isEncrypted());
+		print("Channel: %d\n", espnow.getChannel());
+		print("Lost packets: %d\n", espnow.lost);
+	} else if (WiFi.getMode() == WIFI_MODE_AP) {
 		print("Mode: Access Point (AP)\n");
 		print("MAC: %s\n", WiFi.softAPmacAddress().c_str());
 		print("SSID: %s\n", WiFi.softAPSSID().c_str());
 		print("Password: ***\n");
+		print("Channel: %d\n", WiFi.channel());
 		print("Clients: %d\n", WiFi.softAPgetStationNum());
 		print("IP: %s\n", WiFi.softAPIP().toString().c_str());
+		print("Remote IP: %s\n", udpRemoteIP.toString().c_str());
 	} else if (WiFi.getMode() == WIFI_MODE_STA) {
 		print("Mode: Client (STA)\n");
 		print("Connected: %d\n", WiFi.isConnected());
 		print("MAC: %s\n", WiFi.macAddress().c_str());
 		print("SSID: %s\n", WiFi.SSID().c_str());
 		print("Password: ***\n");
+		print("Channel: %d\n", WiFi.channel());
+		print("RSSI: %d dBm\n", WiFi.RSSI());
 		print("IP: %s\n", WiFi.localIP().toString().c_str());
+		print("Remote IP: %s\n", udpRemoteIP.toString().c_str());
 	} else {
 		print("Mode: Disabled\n");
-		return;
 	}
-	print("Remote IP: %s\n", udpRemoteIP.toString().c_str());
-	print("MAVLink connected: %d\n", mavlinkConnected);
+	print("MAVLink connected: %d\n", valid(mavlinkTime));
 }

-void configWiFi(bool ap, const char *ssid, const char *password) {
-	if (ap) {
-		storage.putString("WIFI_AP_SSID", ssid);
-		storage.putString("WIFI_AP_PASS", password);
+void configWiFi(int mode, const char *first, const char *second) {
+	MacAddress mac;
+	if (mode == W_AP && strlen(first) > 0 && strlen(second) >= 8) {
+		storage.putString("WIFI_AP_SSID", first);
+		storage.putString("WIFI_AP_PASS", second);
+	} else if (mode == W_STA && strlen(first) > 0 && strlen(second) >= 8) {
+		storage.putString("WIFI_STA_SSID", first);
+		storage.putString("WIFI_STA_PASS", second);
+	} else if (mode == W_ESPNOW && mac.fromString(first)) {
+		storage.putString("ESPNOW_PEER_MAC", first);
+		storage.putString("ESPNOW_PEER_KEY", strlen(second) == ESP_NOW_KEY_LEN ? second : "");
 	} else {
-		storage.putString("WIFI_STA_SSID", ssid);
-		storage.putString("WIFI_STA_PASS", password);
+		print("Invalid configuration\n");
+		return;
 	}
 	print("✓ Reboot to apply new settings\n");
 }
+
+void setWiFiMode(const String& mode) {
+	if (mode == "ap") {
+		wifiMode = W_AP;
+	} else if (mode == "sta") {
+		wifiMode = W_STA;
+	} else if (mode == "espnow") {
+		wifiMode = W_ESPNOW;
+	} else if (mode == "off") {
+		wifiMode = W_DISABLED;
+	} else {
+		print("Invalid Wi-Fi mode\n");
+		return;
+	}
+	static const char *modes[] = {"Disabled", "Access Point (AP)", "Client (STA)", "ESP-NOW"};
+	print("✓ Wi-Fi mode set to %s, reboot to apply\n", modes[wifiMode]);
+}
@@ -20,7 +20,13 @@
 #define radians(deg) ((deg)*DEG_TO_RAD)
 #define degrees(rad) ((rad)*RAD_TO_DEG)

+#define MALLOC_CAP_SPIRAM (1<<10)
+#define MALLOC_CAP_8BIT (1<<2)
+#define ESP_NOW_MAX_DATA_LEN_V2 1470
+
 #define constrain(amt,low,high) ((amt)<(low)?(low):((amt)>(high)?(high):(amt)))
+template<typename T> T max(T a, T b) { return a > b ? a : b; }
+template<typename T> T min(T a, T b) { return a < b ? a : b; }

 long map(long x, long in_min, long in_max, long out_min, long out_max) {
 	const long run = in_max - in_min;
@@ -149,11 +155,13 @@ public:
 	void setRxInvert(bool invert) {};
 };

-HardwareSerial Serial, Serial2;
+HardwareSerial Serial, Serial1, Serial2;

 class EspClass {
 public:
 	void restart() { Serial.println("Ignore reboot in simulation"); }
+	uint32_t getFreeHeap() { return 300 * 1024; } // assume 300 KB free heap
+	uint32_t getFreePsram() { return 8 * 1024 * 1024; } // assume 8 MB free PSRAM
 } ESP;

 unsigned long __delayTime = 0;
@@ -163,9 +171,16 @@ void delay(uint32_t ms) {
 	__delayTime += ms * 1000;
 }

+void *heap_caps_calloc(size_t n, size_t size, uint32_t caps) {
+	return calloc(n, size);
+}
+
 bool ledcAttach(uint8_t pin, uint32_t freq, uint8_t resolution) { return true; }
 bool ledcWrite(uint8_t pin, uint32_t duty) { return true; }
 uint32_t ledcChangeFrequency(uint8_t pin, uint32_t freq, uint8_t resolution) { return freq; }
+int8_t digitalPinToAnalogChannel(uint8_t pin) { return -1; }
+uint32_t analogReadMilliVolts(uint8_t pin) { return 0; }
+float temperatureRead() { return 0; }

 unsigned long __micros;
 unsigned long __resetTime = 0;
@@ -0,0 +1,12 @@
+// Dummy file for the simulator
+
+class ESP_NOW_Peer {
+protected:
+	size_t send(const uint8_t *data, int len) { return 0; }
+};
+
+class ESP_NOW_Serial_Class : public ESP_NOW_Peer {
+public:
+	virtual void onSent(bool success) {};
+	virtual size_t write(const uint8_t *data, size_t len) { return 0; };
+};
@@ -15,12 +15,11 @@ public:
 	SBUS(HardwareSerial& bus, const int8_t rxpin, const int8_t txpin, const bool inv = true) {};
 	void begin(int rxpin = -1, int txpin = -1, bool inv = true, bool fast = false) {};
 	bool read() { return joystickInit(); };
-	SBUSData data() {
-		SBUSData data;
-		joystickGet(data.ch);
+	void getChannels(uint16_t (&channels)[16]) const {
+		int16_t ch[16];
+		joystickGet(ch);
 		for (int i = 0; i < 16; i++) {
-			data.ch[i] = map(data.ch[i], -32768, 32767, 1000, 2000); // convert to pulse width style
+			channels[i] = map(ch[i], -32768, 32767, 1000, 2000); // convert to pulse width style
 		}
-		return data;
 	};
 };
@@ -9,7 +9,7 @@
 #include "quaternion.h"
 #include "Arduino.h"
 #include "wifi.h"
-#include "lpf.h"
+#include "filter.h"

 extern float t, dt;
 extern float controlRoll, controlPitch, controlYaw, controlThrottle, controlMode;
@@ -21,32 +21,47 @@ extern float motors[4];
 Vector gyro, acc, imuRotation;
 Vector accBias, gyroBias, accScale(1, 1, 1);
 LowPassFilter<Vector> gyroBiasFilter(0);
+int imuModel = 1, imuBus = 0;
+int imuSckPin = 0, imuMisoPin = 0, imuMosiPin = 0, imuCsPin = -1, imuIntPin = -1;
+int imuSdaPin = 0, imuSclPin = 0;

 // declarations
 void step();
 void computeLoopRate();
 void applyGyro();
 void applyAcc();
+void applyLevel();
 void control();
 void interpretControls();
 void controlAttitude();
 void controlRates();
 void controlTorque();
+void desaturate(float& a, float& b, float& c, float& d);
 const char* getModeName();
 void sendMotors();
 int getDutyCycle(float value);
 bool motorsActive();
-void testMotor(int n);
+void testMotor(int, float);
 void print(const char* format, ...);
 void pause(float duration);
 void doCommand(String str, bool echo);
 void handleInput();
+void setupRC();
 void normalizeRC();
 void calibrateRC();
-void calibrateRCChannel(int *channel, uint16_t zero[16], uint16_t max[16], const char *str);
+void calibrateRCChannel(int*, uint16_t[16], uint16_t[16], const char*);
 void printRCCalibration();
+void loopLog();
+void resetLog();
+void writeLog(const void *data, size_t size);
+void readLog(void *data, size_t position, size_t size);
+bool isTopicUpdated(const uint8_t topic);
+void printLogInfo();
+int estimateLogDuration();
 void printLogHeader();
-void printLogData();
+void printLogValues(const char *filter);
+void configLogThrottle(const char *name, float throttle);
+void exposeLogValue(const char *name);
 void processMavlink();
 void sendMavlink();
 void sendMessage(const void *msg);
@@ -55,23 +70,30 @@ void handleMavlink(const void *_msg);
 void mavlinkPrint(const char* str);
 void sendMavlinkPrint();
 inline Quaternion fluToFrd(const Quaternion &q);
+void setupPower();
 void failsafe();
 void rcLossFailsafe();
 void descend();
 void autoFailsafe();
+void tiltFailsafe();
 int parametersCount();
 const char *getParameterName(int index);
 float getParameter(int index);
 float getParameter(const char *name);
 bool setParameter(const char *name, const float value);
-void printParameters();
+void printParameters(const char *filter);
 void resetParameters();

 // mocks
 void setLED(bool on) {};
-void calibrateGyro() { print("Skip gyro calibrating\n"); };
 void calibrateAccel() { print("Skip accel calibrating\n"); };
 void printIMUCalibration() { print("cal: N/A\n"); };
 void printIMUInfo() {};
 void printWiFiInfo() {};
 void configWiFi(bool, const char*, const char*) { print("Skip WiFi config\n"); };
+void setWiFiMode(const String& mode) { print("Skip WiFi mode set\n"); };
+
+class IMU {
+public:
+	float getTemp() { return 0; }
+} *imu;
@@ -23,10 +23,11 @@
 #include "estimate.ino"
 #include "safety.ino"
 #include "log.ino"
-#include "lpf.h"
+#include "filter.h"
 #include "mavlink.ino"
 #include "motors.ino"
 #include "parameters.ino"
+#include "power.ino"
 #include "rc.ino"
 #include "time.ino"

@@ -54,6 +55,8 @@ public:
 		initNode();
 		Serial.begin(0);
 		setupParameters();
+		setupLog();
+		rcRxPin = 1; // set rc pin to enable rc reading
 		gzmsg << "Flix plugin loaded" << endl;
 	}

@@ -72,6 +75,8 @@ public:
 		gyro = Vector(imu->AngularVelocity().X(), imu->AngularVelocity().Y(), imu->AngularVelocity().Z());
 		acc = this->accFilter.update(Vector(imu->LinearAcceleration().X(), imu->LinearAcceleration().Y(), imu->LinearAcceleration().Z()));

+		voltage = 4.2f; // dummy voltage value
+
 		readRC();
 		estimate();

@@ -84,7 +89,7 @@ public:

 		applyMotorForces();
 		publishTopics();
-		logData();
+		loopLog();
 		syncParameters();
 	}

@@ -1,4 +1,3 @@
 // Dummy file to make it possible to compile simulator with Flix' util.h

-#define WRITE_PERI_REG(addr, val) {}
 #define REG_CLR_BIT(_r, _b) {}
@@ -11,7 +11,13 @@
 #include <sys/poll.h>
 #include <gazebo/gazebo.hh>

-int wifiMode = 1; // mock
+// Mocks
+int wifiMode = 1;
+int wifiLongRange = 0;
+int wifiBroadcast = 0;
+int espnowChannel = 6;
+const int W_DISABLED = 0, W_AP = 1, W_STA = 2, W_ESPNOW = 3;
+
 int udpLocalPort = 14580;
 int udpRemotePort = 14550;
 const char *udpRemoteIP = "255.255.255.255";
@@ -9,6 +9,7 @@ Usage:
 import csv
 import json
 import docopt
+import math
 from mcap.writer import Writer

 args = docopt.docopt(__doc__)
@@ -39,7 +40,15 @@ channel_id = writer.register_channel(
 )

 for row in csv_reader:
-    data = {key: float(value) for key, value in zip(header, row)}
+    if row[0] == '': continue
+    data = {}
+    for key, value in zip(header, row):
+        if value == '' or math.isnan(float(value)):
+            data[key] = None
+        else:
+            data[key] = float(value)
+
+    data = {key: float(value) if value != '' else None for key, value in zip(header, row)}
    timestamp = round(float(row[0]) * 1e9)
    writer.add_message(channel_id=channel_id, log_time=timestamp, data=json.dumps(data).encode(), publish_time=timestamp,)

@@ -0,0 +1,3 @@
+# ESPNOW-proxy
+
+Proxy sketch for using ESP-NOW connection with Flix drone.
@@ -0,0 +1,88 @@
+// Copyright (c) 2026 Oleg Kalachev <okalachev@gmail.com>
+// Repository: https://github.com/okalachev/flix
+
+// Proxy for ESP-NOW connection
+
+#include <vector>
+#include <WiFi.h>
+#include <ESP32_NOW_Serial.h>
+#include <MacAddress.h>
+#include <MAVLink.h>
+#include <Preferences.h>
+#include "../../flix/util.h"
+
+const int CHANNEL = 6;
+char key[ESP_NOW_KEY_LEN + 1] = {0}; // with trailing null
+
+Preferences storage;
+
+std::vector<ESPNOWSerial *> peers;
+
+void onNewPeer(const esp_now_recv_info_t *info, const uint8_t *data, int len, void *arg) {
+	if (len != 4 || memcmp(data, "flix", 4) != 0) return; // check if discovery message
+
+	Serial.printf("New peer: " MACSTR "\n", MAC2STR(info->src_addr));
+	ESPNOWSerial *link = new ESPNOWSerial(info->src_addr, CHANNEL, WIFI_IF_AP);
+	link->begin();
+	link->setKey((const uint8_t *)key);
+	peers.push_back(link);
+}
+
+void setup() {
+	Serial.begin(115200);
+	WiFi.mode(WIFI_AP);
+	WiFi.setSleep(false);
+	WiFi.setChannel(CHANNEL);
+
+	ESP_NOW.onNewPeer(onNewPeer, NULL);
+	ESP_NOW.begin();
+
+	storage.begin("espnow-proxy");
+	if (!storage.isKey("key")) {
+		generateRandomKey();
+		storage.putString("key", key);
+	}
+	strcpy(key, storage.getString("key").c_str());
+
+	// Discover the first peer
+	while (peers.empty()) {
+		Serial.printf("espnow %s %s\n", WiFi.softAPmacAddress().c_str(), key);
+		delay(500);
+	}
+}
+
+void generateRandomKey() {
+	const char chars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789!@#$%^&*-_+=";
+	for (int i = 0; i < ESP_NOW_KEY_LEN; i++) {
+		key[i] = chars[random(0, strlen(chars))];
+	}
+}
+
+void loop() {
+	uint8_t buf[5000];
+
+	// Send from Serial to ESP-NOW
+	while (Serial.available() > 0) {
+		int b = Serial.read();
+		if (b < 0) {
+			break;
+		}
+
+		mavlink_message_t msg;
+		mavlink_status_t status;
+		if (mavlink_parse_char(MAVLINK_COMM_0, (uint8_t)b, &msg, &status)) {
+			int len = mavlink_msg_to_send_buffer(buf, &msg);
+			for (ESPNOWSerial *link : peers) {
+				link->write(buf, len);
+			}
+		}
+	}
+
+	// Send from ESP-NOW to Serial
+	for (ESPNOWSerial *link : peers) {
+		int len = link->read(buf, sizeof(buf));
+		if (len > 0) {
+			Serial.write(buf, len);
+		}
+	}
+}
@@ -10,6 +10,7 @@ print('Connected:', flix.connected)
 print('Mode:', flix.mode)
 print('Armed:', flix.armed)
 print('Landed:', flix.landed)
+print('Voltage:', flix.voltage, 'V')
 print('Rates:', *[f'{math.degrees(r):.0f}°/s' for r in flix.rates])
 print('Attitude:', *[f'{math.degrees(a):.0f}°' for a in flix.attitude_euler])
 print('Motors:', flix.motors)
@@ -0,0 +1,76 @@
+#!/usr/bin/env python3
+
+"""Convert flight from Flix format to CSV
+
+Usage:
+    log_to_csv.py <input_file>
+"""
+
+import os
+from pyflix import Flix
+import docopt
+import struct
+import csv
+
+DIR = os.path.dirname(os.path.realpath(__file__))
+HEADER_FILE = os.path.join(DIR, 'log/log_header.txt')
+
+# Read log header
+try:
+    # read from file
+    header = open(HEADER_FILE, 'r').read()
+except FileNotFoundError:
+    flix = Flix()
+    header = flix.cli('log header')  # receive the log schema
+    open(HEADER_FILE, 'w').write(header)  # save to file
+
+# Parse log header
+topics = []
+for line in header.splitlines():
+    if not line.startswith('  '):
+        topics.append([])
+    elif 'not logged' not in line:
+        topics[-1].append(line.strip())
+
+# Read log file
+args = docopt.docopt(__doc__)
+input_file = args['<input_file>']
+outfile_file = input_file + '.csv'
+data = open(input_file, 'rb').read()
+
+# Search for sync marker
+SYNC_MARKER = bytes.fromhex('1A 91 4F F6 7F')
+sync_offset = data.find(SYNC_MARKER)
+if sync_offset == -1:
+    raise ValueError('Sync marker not found in log file')
+data = data[sync_offset + len(SYNC_MARKER):]
+data = data.replace(SYNC_MARKER, b'')  # remove all other sync markers
+
+header_row = [f'{value}' for topic in topics for value in topic]
+rows = []
+
+offset = 0
+while offset < len(data):
+    try:
+        topic = struct.unpack_from('B', data, offset)[0]
+        offset += 1
+
+        if topic >= len(topics):
+            raise ValueError(f'Invalid topic {topic} at offset {offset}')
+
+        if topic == 0 or not rows:
+            rows.append({})
+
+        for name in topics[topic]:
+            value = struct.unpack_from('<f', data, offset)[0]
+            offset += 4
+            rows[-1][name] = value
+    except struct.error as e:
+        break
+
+# Write CSV file
+with open(outfile_file, 'w', newline='') as f:
+    writer = csv.DictWriter(f, fieldnames=header_row, extrasaction='ignore')
+    writer.writeheader()
+    rows = filter(lambda row: float(row.get('t', 0)), rows)
+    writer.writerows(rows)
@@ -24,19 +24,22 @@ pip install pyflix
 The API is accessed through the `Flix` class:

 ```python
-from flix import Flix
+from pyflix import Flix
 flix = Flix()  # create a Flix object and wait for connection
 ```

+If using ESP-NOW connection, specify the proxy device name in `FLIX_DEVICE` environment variable or pass it to the constructor: `Flix(device='/dev/cu.usbserial-0001')`.
+
 ### Telemetry

-Basic telemetry is available through object properties. The property names generally match the corresponding variables in the firmware itself:
+Basic telemetry is available through object properties. The property names generally match the corresponding variables in the firmware code:

 ```python
 print(flix.connected)       # True if connected to the drone
 print(flix.mode)            # current flight mode (str)
 print(flix.armed)           # True if the drone is armed
 print(flix.landed)          # True if the drone is landed
+print(flix.voltage)         # battery voltage (NaN - unknown, ~0 - USB powered)
 print(flix.attitude)        # attitude quaternion [w, x, y, z]
 print(flix.attitude_euler)  # attitude as Euler angles [roll, pitch, yaw]
 print(flix.rates)           # angular rates [roll_rate, pitch_rate, yaw_rate]
@@ -95,6 +98,7 @@ Full list of events:
 |`armed`|Armed state update|Armed state *(bool)*|
 |`mode`|Flight mode update|Flight mode *(str)*|
 |`landed`|Landed state update|Landed state *(bool)*|
+|`voltage`|Battery voltage update|Voltage *(float)*|
 |`print`|The drone prints text to the console|Text|
 |`attitude`|Attitude update|Attitude quaternion *(list)*|
 |`attitude_euler`|Attitude update|Euler angles *(list)*|
@@ -218,6 +222,13 @@ The following scripts demonstrate how to use the library:
 * [`log.py`](../log.py) — download flight logs from the drone.
 * [`example.py`](../example.py) — a simple example, prints telemetry data and waits for events.

+> [!TIP]
+> Set `FLIX_DEVICE` environment variable to use these tools with ESP-NOW connection, for example:
+>
+> ```bash
+> FLIX_DEVICE=/dev/cu.usbserial-0001 tools/cli.py
+> ```
+
 ## Advanced usage

 ### MAVLink
@@ -5,6 +5,7 @@

 import os
 import time
+import math
 from queue import Queue, Empty
 from typing import Optional, Callable, List, Dict, Any, Union, Sequence
 import logging
@@ -26,6 +27,7 @@ class Flix:
    mode: str = ''
    armed: bool = False
    landed: bool = False
+    voltage: float = math.nan
    attitude: List[float]
    attitude_euler: List[float]  # roll, pitch, yaw
    rates: List[float]
@@ -42,22 +44,27 @@ class Flix:
    _print_buffer: str = ''
    _modes = ['RAW', 'ACRO', 'STAB', 'AUTO']

-    def __init__(self, system_id: int=1, wait_connection: bool=True):
+    def __init__(self, system_id: int=1, wait_connection: bool=True, device=os.getenv('FLIX_DEVICE')):
        if not (0 <= system_id < 256):
            raise ValueError('system_id must be in range [0, 255]')
        self._setup_mavlink()
        self.system_id = system_id
        self._init_state()
-        try:
-            # Direct connection
-            logger.debug('Listening on port 14550')
-            self.connection: mavutil.mavfile = mavutil.mavlink_connection('udpin:0.0.0.0:14550', source_system=255)  # type: ignore
-        except OSError as e:
-            if e.errno != errno.EADDRINUSE:
-                raise
-            # Port busy - using proxy
-            logger.debug('Listening on port 14555 (proxy)')
-            self.connection: mavutil.mavfile = mavutil.mavlink_connection('udpin:0.0.0.0:14555', source_system=254)  # type: ignore
+        if device is not None:
+            # User defined connection
+            logger.debug(f'Connecting to {device}')
+            self.connection: mavutil.mavfile = mavutil.mavlink_connection(device, source_system=255)  # type: ignore
+        else:
+            try:
+                # Direct connection
+                logger.debug('Listening on port 14550')
+                self.connection: mavutil.mavfile = mavutil.mavlink_connection('udpin:0.0.0.0:14550', source_system=255)  # type: ignore
+            except OSError as e:
+                if e.errno != errno.EADDRINUSE:
+                    raise
+                # Port busy - using proxy
+                logger.debug('Listening on port 14555 (proxy)')
+                self.connection: mavutil.mavfile = mavutil.mavlink_connection('udpin:0.0.0.0:14555', source_system=254)  # type: ignore
        self.connection.target_system = system_id
        self.mavlink: mavlink.MAVLink = self.connection.mav
        self._event_listeners: Dict[str, List[Callable[..., Any]]] = {}
@@ -68,7 +75,7 @@ class Flix:
        self._heartbeat_thread.start()
        if wait_connection:
            self.wait('mavlink.HEARTBEAT')
-            time.sleep(0.2) # give some time to receive initial state
+            time.sleep(0.6) # give some time to receive initial state

    def _init_state(self):
        self.attitude = [1, 0, 0, 0]
@@ -185,11 +192,16 @@ class Flix:
            self._trigger('motors', self.motors)

        if isinstance(msg, mavlink.MAVLink_scaled_imu_message):
-            self.acc = self._mavlink_to_flu([msg.xacc / 1000, msg.yacc / 1000, msg.zacc / 1000])
+            ONE_G = 9.80665
+            self.acc = self._mavlink_to_flu([msg.xacc * ONE_G / 1000, msg.yacc * ONE_G / 1000, msg.zacc * ONE_G / 1000])
            self.gyro = self._mavlink_to_flu([msg.xgyro / 1000, msg.ygyro / 1000, msg.zgyro / 1000])
            self._trigger('acc', self.acc)
            self._trigger('gyro', self.gyro)

+        if isinstance(msg, mavlink.MAVLink_battery_status_message):
+            self.voltage = msg.voltages[0] / 1000
+            self._trigger('voltage', self.voltage)
+
        if isinstance(msg, mavlink.MAVLink_serial_control_message):
            # new chunk of data
            text = bytes(msg.data)[:msg.count].decode('utf-8', errors='ignore')
@@ -231,7 +243,7 @@ class Flix:
            time.sleep(1)

    @staticmethod
-    def _mavlink_to_flu(v: List[float]) -> List[float]:
+    def _mavlink_to_flu(v: Sequence[float]) -> List[float]:
        if len(v) == 3:  # vector
            return [v[0], -v[1], -v[2]]
        elif len(v) == 4:  # quaternion
@@ -240,8 +252,8 @@ class Flix:
            raise ValueError(f'List must have 3 (vector) or 4 (quaternion) elements')

    @staticmethod
-    def _flu_to_mavlink(v: List[float]) -> List[float]:
-        return Flix._mavlink_to_flu(v)
+    def _flu_to_mavlink(v: Sequence[float]) -> List[float]:
+        return Flix._mavlink_to_flu(v)  # flu to mavlink is the same as mavlink to flu

    def _command_send(self, command: int, params: Sequence[float]):
        if len(params) != 7:
@@ -308,13 +320,13 @@ class Flix:
    def set_armed(self, armed: bool):
        self._command_send(mavlink.MAV_CMD_COMPONENT_ARM_DISARM, (1 if armed else 0, 0, 0, 0, 0, 0, 0))

-    def set_position(self, position: List[float], yaw: Optional[float] = None, wait: bool = False, tolerance: float = 0.1):
+    def set_position(self, position: Sequence[float], yaw: Optional[float] = None, wait: bool = False, tolerance: float = 0.1):
        raise NotImplementedError('Position control is not implemented yet')

-    def set_velocity(self, velocity: List[float], yaw: Optional[float] = None):
+    def set_velocity(self, velocity: Sequence[float], yaw: Optional[float] = None):
        raise NotImplementedError('Velocity control is not implemented yet')

-    def set_attitude(self, attitude: List[float], thrust: float):
+    def set_attitude(self, attitude: Sequence[float], thrust: float, rates_extra: Sequence[float] = (0, 0, 0)):
        if len(attitude) == 3:
            attitude = Quaternion([attitude[0], attitude[1], attitude[2]]).q  # type: ignore
        elif len(attitude) != 4:
@@ -322,12 +334,13 @@ class Flix:
        if not (0 <= thrust <= 1):
            raise ValueError('Thrust must be in range [0, 1]')
        attitude = self._flu_to_mavlink(attitude)
+        rates_extra = self._flu_to_mavlink(rates_extra)
        for _ in range(2): # duplicate to ensure delivery
            self.mavlink.set_attitude_target_send(0, self.system_id, 0, 0,
                [attitude[0], attitude[1], attitude[2], attitude[3]],
-                0, 0, 0, thrust)
+                rates_extra[0], rates_extra[1], rates_extra[2], thrust)

-    def set_rates(self, rates: List[float], thrust: float):
+    def set_rates(self, rates: Sequence[float], thrust: float):
        if len(rates) != 3:
            raise ValueError('Rates must be [roll_rate, pitch_rate, yaw_rate]')
        if not (0 <= thrust <= 1):
@@ -339,7 +352,7 @@ class Flix:
                [1, 0, 0, 0],
                rates[0], rates[1], rates[2], thrust)

-    def set_motors(self, motors: List[float]):
+    def set_motors(self, motors: Sequence[float]):
        if len(motors) != 4:
            raise ValueError('motors must have 4 values')
        if not all(0 <= m <= 1 for m in motors):
@@ -1,6 +1,6 @@
 [project]
 name = "pyflix"
-version = "0.11"
+version = "0.16"
 description = "Python API for Flix drone"
 authors = [{ name="Oleg Kalachev", email="okalachev@gmail.com" }]
 license = "MIT"
Author	SHA1	Message	Date
Oleg Kalachev	bbe753add0	Enable motor pins only for classic esp32 by default Also simplify flix2 config code.	2026-08-16 01:26:34 +03:00
Oleg Kalachev	815ccfc08f	Docs fix	2026-08-16 00:10:19 +03:00
Oleg Kalachev	3f11fa11e8	Test simulation run	2026-08-14 09:41:35 +03:00
Oleg Kalachev	a05e35540e	Bring back simpler version of Value::set	2026-08-14 06:18:17 +03:00
Oleg Kalachev	6098293776	Utilize Value class in parameters for Now bool parameters also may be used.	2026-08-14 06:11:43 +03:00
Oleg Kalachev	2d1efac05f	Change type hints of the most List arguments to Sequence in pyflix These arguments are effectively immutable, so Sequence makes more sense - the user may use tuples in addition to lists.	2026-08-14 05:57:58 +03:00
Oleg Kalachev	f99a9998b1	Add rates_extra argument to pyflix' set_attitude method For controlling rates feed forward.	2026-08-14 05:32:39 +03:00
Oleg Kalachev	4d77c6c369	Simply set_attitude_target handler Rates ignore flags are efficiently the same as zeros, so can be ignored.	2026-08-14 05:21:45 +03:00
Oleg Kalachev	94c70994b6	Fix simulation run	2026-08-14 04:19:25 +03:00
Oleg Kalachev	78be5b3a8d	Minor changes	2026-08-14 03:15:27 +03:00
Oleg Kalachev	9b1f0bd593	Remove test line	2026-08-14 03:04:00 +03:00
Oleg Kalachev	b72a10dd7b	Trigger build	2026-08-14 02:25:29 +03:00
Oleg Kalachev	d2d1c74842	Update all used actions Some of them were deprecated.	2026-08-14 01:51:21 +03:00
Oleg Kalachev	7308159b74	Show cloc diff with the previous commit	2026-08-14 01:41:57 +03:00
Oleg Kalachev	87ce9c20cb	Count and print sloc count in tools workflow	2026-08-14 01:30:51 +03:00
Oleg Kalachev	d6b9228282	Fix default windup value in pid INFINITY makes much more sense, since otherwise i term would be ineffective at all by default	2026-08-13 02:21:03 +03:00
Oleg Kalachev	f355cc2938	Upload binaries to docs only in my repo and in master and dev branches	2026-08-12 07:19:23 +03:00
Oleg Kalachev	0139d71b12	Show git hash commit in sys command	2026-08-12 01:58:13 +03:00
Oleg Kalachev	58da0b9959	Add binaries to the docs only of DOCS_BINARIES repo variable is truthy	2026-08-11 21:28:16 +03:00
Oleg Kalachev	355f4ad49d	Merge remote-tracking branch 'origin/master' into dev	2026-08-11 18:43:18 +03:00
Oleg Kalachev	55398a660d	Remove unused variable	2026-08-11 04:59:54 +03:00
Oleg Kalachev	63bbea4d8b	Fix	2026-08-11 02:26:20 +03:00
Oleg Kalachev	5543a363b3	Add yaw rate windup parameter	2026-08-11 01:56:49 +03:00
Oleg Kalachev	363c756c00	Fix windup for yaw rate	2026-08-11 01:56:41 +03:00
Oleg Kalachev	57b853361c	Fix motor pins for Flix2	2026-08-11 01:55:56 +03:00
Oleg Kalachev	ce37e5b724	Simplify parameter defaults definition	2026-08-11 00:48:10 +03:00
Oleg Kalachev	36b050a896	Add config for Flix2 board	2026-08-10 03:52:57 +03:00
Oleg Kalachev	93ebf75a44	Fix	2026-08-10 03:51:16 +03:00
Oleg Kalachev	a60c84ce7a	Forgotten image	2026-08-10 03:45:38 +03:00
Oleg Kalachev	ae8931cb25	Move most parameter defaults to config.h	2026-08-10 03:45:28 +03:00
Oleg Kalachev	e6072b0bc4	Make i and d arguments optional in pid constructor	2026-08-10 03:43:37 +03:00
Oleg Kalachev	67e772a23f	Update wait-on-check-action version	2026-08-10 03:33:27 +03:00
Oleg Kalachev	04a24c4939	Add minor comment	2026-08-10 03:27:23 +03:00
Oleg Kalachev	f62e176313	Update the docs to reflect possibility for using prebuilt binaries	2026-08-10 03:17:32 +03:00
Oleg Kalachev	8ae06eef85	Docs updates	2026-08-10 03:16:54 +03:00
Oleg Kalachev	9a17ca848d	Simplify	2026-08-10 02:41:53 +03:00
Oleg Kalachev	b8f93becca	Make Rate always trigger on first step	2026-08-10 02:31:54 +03:00
Oleg Kalachev	5fc2143994	Make brushless motors separated block to avoid confusion	2026-08-10 02:31:14 +03:00
Oleg Kalachev	b7102d395c	Make default fqbn plain esp32 It works on d1 as well	2026-08-10 02:15:30 +03:00
Oleg Kalachev	58ea75d335	Fixes	2026-08-10 01:18:29 +03:00
Oleg Kalachev	93b3077fa7	Add I2C pin parameters	2026-08-09 23:59:45 +03:00
Oleg Kalachev	4c74768131	Fixes	2026-08-09 22:42:14 +03:00
Oleg Kalachev	9880eeccd3	Disable imu by default	2026-08-09 20:41:03 +03:00
Oleg Kalachev	a26d096dc0	Disable motors by default	2026-08-09 20:40:58 +03:00
Oleg Kalachev	8a91201cf4	Add targets with psram	2026-08-09 06:35:54 +03:00
Oleg Kalachev	51ca049b97	Download binaries to docs site	2026-08-09 04:23:16 +03:00
Oleg Kalachev	2decd2d6dd	Fix simulation build	2026-08-08 02:19:38 +03:00
Oleg Kalachev	abb2e9f79b	Use up-to-date method for installing arduino-cli in simulator ci	2026-08-08 02:19:28 +03:00
Oleg Kalachev	6c907b77f6	Fix simulation build	2026-08-08 01:31:41 +03:00
Oleg Kalachev	0a53170097	Make imu configuration parameters work	2026-08-08 01:24:43 +03:00
Oleg Kalachev	6b36488245	Use dev version of FlixPeriph	2026-08-08 01:21:01 +03:00
Oleg Kalachev	f30a182b20	Add parameter WIFI_BROADCAST for always broadcasting mode May be used in some cases, like multiple gcs	2026-08-08 01:04:20 +03:00
Oleg Kalachev	90b506e084	Allow hot reconnection from another gcs over wifi Switch back to udp broadcasting if no messages from gcs for 5 seconds	2026-08-07 18:24:23 +03:00
Oleg Kalachev	5f9aae62b9	Upload all binaries to artifacts	2026-08-06 03:04:05 +03:00
Oleg Kalachev	0e0867ceab	Merge branch 'master' into dev	2026-08-05 01:26:28 +03:00
Oleg Kalachev	8e276bde38	Add Oleg1405 build	2026-08-04 22:48:39 +03:00
Oleg Kalachev	83aac78cf7	Merge branch 'master' into dev	2026-08-03 16:02:29 +03:00
Oleg Kalachev	eb93b0b29d	Merge branch 'master' into dev	2026-08-03 16:01:39 +03:00
Oleg Kalachev	a5991930d1	Disable voltage lpf by default Filtering does more harm than good in voltage monitoring. (alpha = 1 efficiently disables the filter.)	2026-08-03 15:57:29 +03:00
Oleg Kalachev	406f7a4af5	Add tilt disarm failsafe	2026-08-02 02:13:50 +03:00
Oleg Kalachev	5ee6d91440	Don't send discovery message if encrypting is disabled in espnow	2026-08-02 02:07:17 +03:00
Oleg Kalachev	38925d7885	Updates and fixes in usage article	2026-08-02 02:02:28 +03:00
Oleg Kalachev	5c81181221	Add threshold for rc sticks move for quitting auto mode	2026-08-02 01:58:16 +03:00
Oleg Kalachev	fd249fcaa6	Add position control demo video to the readme	2026-08-01 22:33:26 +03:00
Oleg Kalachev	9289b042af	Add espnow-proxy build to ci	2026-07-17 23:45:54 +03:00
Oleg Kalachev	1203a3ae8f	Make imu model and pins configurable using parameters	2026-07-16 23:09:07 +03:00
Oleg Kalachev	d48b71fb1a	Disable voltage lpf by default (Setting alpha = 1 efficiently disables the filter.) Filtering does more harm than good in voltage monitoring.	2026-07-15 18:42:34 +03:00
Oleg Kalachev	8917849711	Remove unneeded declaration from the sim	2026-07-15 18:40:51 +03:00
Oleg Kalachev	1cdc7a8641	Fix rc in simulator Virtual rc is disabled if rxRxPin < 0	2026-07-15 18:40:35 +03:00
Oleg Kalachev	0439407d76	Remove unneeded declaration from the sim	2026-07-15 18:29:36 +03:00
Oleg Kalachev	c2005a2ca2	Fix rc in simulator	2026-07-15 17:40:11 +03:00
Oleg Kalachev	6a804862da	Fix simulator build with new logging	2026-07-15 14:17:24 +03:00
Oleg Kalachev	590bfe10b0	Minor doc changes	2026-07-15 10:52:52 +03:00
Oleg Kalachev	70af1a1c09	Remove DebugLevel from fqbn in usage article	2026-07-15 10:38:04 +03:00
Oleg Kalachev	9e9dafbdfb	Support feed forward rates in mavlink control	2026-07-15 10:11:15 +03:00
Oleg Kalachev	86a4418813	Move debug level definition from fbqn to arduino-cli commaand	2026-07-13 22:05:31 +03:00
Oleg Kalachev	d64bf24c6d	Add alicanerus' build	2026-07-08 22:29:33 +03:00
Oleg Kalachev	7c53e88963	Add notch filter for the gyro	2026-07-08 16:07:03 +03:00
Oleg Kalachev	28f015569b	Add log reset command to cli	2026-07-08 01:07:59 +03:00
Oleg Kalachev	fabd5e072d	Fixes in the docs	2026-07-04 21:40:39 +03:00
Oleg Kalachev	1ae85ff118	Add argument to motor testing commands for specifying thrust	2026-07-02 22:22:33 +03:00
Oleg Kalachev	83d1c5c68a	Implement entirely new logging subsystem Make topic-based logging mechanics. Print any log value to console. Possibility to expose any logging value to mavlink.	2026-06-30 13:03:43 +03:00
Oleg Kalachev	26a0dd65be	Minor fixes and updates	2026-06-30 12:19:29 +03:00
Oleg Kalachev	9d439afd80	Store only changed parameters in flash instead of all Rationale: 1. Parameters NVS storage is limited and storing unchanged parameters is wasteful. 2. This allows changing parameters in the code without having to erase the flash storage. 3. Updating the firmware version may change the parameter defaults.	2026-06-28 17:21:07 +03:00
Oleg Kalachev	64b21a3a6b	Show default parameter values in `p` command output Also move float comparing logic to a distinct util function.	2026-06-24 06:42:09 +03:00
Oleg Kalachev	545eed8944	Add Nerush and Konstantinos Paraskevas builds	2026-06-19 05:15:17 +03:00
Oleg Kalachev	518abf1555	Simplify rc code Utilize the new method for getting channel values.	2026-06-14 04:45:42 +03:00
Oleg Kalachev	17df1c5396	Separate repository vscode settings and local vscode settings Use dangmai.workspace-default-settings externsion for that.	2026-06-11 20:37:35 +03:00
Oleg Kalachev	8e2ffd7c69	Remove core installation when running the sim Split `dependencies` target to `core` and `libs` targets. Move additional urls declaration and connection timeout from arduino-cli.yaml to Makefile for simplicity and transparency. Update ESP32 core url. Remove arduino-cli.yaml.	2026-06-10 18:10:42 +03:00
Oleg Kalachev	52b74afba6	Bring back espnow tx buffering keeping resends disabled Buffering is needed for sending large prints, otherwise the espnow internal buffer overflows. Make onSent always think there was success send, so there won't be any resends. Print lost espnow packets count on wifi console command.	2026-06-09 03:23:30 +03:00
Oleg Kalachev	0ca2473655	Make each mavlink message rate configured separately Add parameters: * MAV_RATE_ATT - ATTITUDE_QUATERNION rate. * MAV_RATE_RC - RC_CHANNELS_RAW rate. * MAV_RATE_MOT - ACTUATOR_CONTROL_TARGET rate. * MAV_RATE_IMU - SCALED_IMU rate.	2026-06-09 02:59:10 +03:00
Oleg Kalachev	b4c2fe3988	Print total RAM in sys command	2026-06-09 02:49:39 +03:00
Oleg Kalachev	e51b47b798	Add command for setting the wifi mode easier	2026-06-09 02:44:09 +03:00
Oleg Kalachev	71abe1bcdb	Minor changes Simplify the code, print imu temperature	2026-06-09 02:25:20 +03:00
Oleg Kalachev	0f2e384ce6	Don't apply level correction on idle thrust	2026-06-09 02:12:27 +03:00
Oleg Kalachev	5e153a210d	Update ESP32-Core to 3.3.10	2026-06-09 02:05:52 +03:00
Oleg Kalachev	9d47bcb82e	Minor changes in docs	2026-05-31 18:10:00 +03:00
Oleg Kalachev	1fafc27b39	Make it possible to unassign motor pin using -1 parameter value	2026-05-30 16:57:27 +03:00
Oleg Kalachev	faca48ced3	Replace ps and psq commands with st command + minor changes Re-arrange commands order. Make command parser consider \r in addition to \n.	2026-05-30 16:51:15 +03:00
Oleg Kalachev	a5dbd2c829	Add erase command to makefile	2026-05-30 16:48:12 +03:00
Oleg Kalachev	59f9528d34	Increase buffer for print, make sys output more correct usStackHighWaterMark is not stack size, it's the minimum stack size	2026-05-30 11:11:35 +03:00
Oleg Kalachev	607b2ff0b7	Add malagis custom pcb version of Flix project to builds	2026-05-28 20:15:09 +03:00
Oleg Kalachev	22c06f76c4	Add Awab Anas' build	2026-05-28 19:29:05 +03:00
Oleg Kalachev	488ceb3004	Set the debug level to error by default to see the errors	2026-05-28 19:25:29 +03:00
Oleg Kalachev	b83c9b3845	Consider mavlink connected only when the gcs message is parsed	2026-05-28 18:41:34 +03:00
Oleg Kalachev	2f4b1423e6	Typo and minor code style changes	2026-05-28 18:39:44 +03:00
Oleg Kalachev	4e32414dae	Support ESP-NOW connection in pyflix Set arbitrary pymavlink connection string using device parameter or FLIX_DEVICE env variable. pyflix@0.16.	2026-05-28 18:22:16 +03:00
Oleg Kalachev	a294883dea	Make p command show all parameters starting with the arg	2026-05-27 13:58:51 +03:00
Oleg Kalachev	cdfba72a0b	Fix simulator run Add missing extern variables. Fix warning.	2026-05-27 11:03:50 +03:00
Oleg Kalachev	18e81720e0	Add video of pcb version flights to the readme	2026-05-26 14:23:56 +03:00
Oleg Kalachev	91173d06c9	Various minor changes	2026-05-22 08:03:46 +03:00
Oleg KalachevandGitHub	fdcc9533b3	Implement ESP-NOW support (#40 )	2026-05-21 10:48:31 +03:00
Oleg Kalachev	bd2b1bd5de	Improve voltage measurement Apply PWM_VOLT_PIN without reboot. Check if the voltage pin can be used with ADC when setting up. Set voltage to NAN, when it's unknown (including pyflix). pyflix@0.15. Don't send BATTERY_STATUS when voltage is unknown. Add dummy voltage to the simulator.	2026-05-18 00:30:42 +03:00
Oleg Kalachev	4530c05b5c	Add Flix 1.5 to builds	2026-05-17 06:46:11 +03:00
Oleg Kalachev	3816ae376f	Bring back initializing the lpf with the first input value It's much better for voltage measuring and slightly better for gyro bias estimation.	2026-05-17 06:21:13 +03:00
Oleg Kalachev	72a72fde80	Some docs improvements	2026-05-14 21:59:15 +03:00
Oleg Kalachev	e53051a349	Fix console command parsing	2026-05-13 06:00:51 +03:00
Oleg Kalachev	f8a9f1f838	Remove reboot requirement when changing RC_RX_PIN	2026-05-13 01:27:01 +03:00
Oleg Kalachev	76af83fc88	Improve firmware overview article	2026-05-13 00:35:43 +03:00
Oleg Kalachev	dd176180a7	Update help message Remove 'welcome to', add copyright and repo link.	2026-05-12 17:50:28 +03:00
Oleg Kalachev	48c33c7050	Fix and improve wifi subsystem Fix a fault when wifi is disabled (udp can't be used without wifi). Print RSSI and channel in wifi command.	2026-05-10 22:39:34 +03:00
Oleg Kalachev	35e94f6ea6	Support ESP32-C3 User Serial1 for rc instead of Serial2, as ESP32-C3 has only 2 Serials. Add CI build for ESP32-C3.	2026-05-10 21:07:20 +03:00
Oleg Kalachev	1f48e379e3	Improve the rc calibration code More convenient steps order. Improve the readability a bit.	2026-05-10 19:05:27 +03:00
Oleg Kalachev	ee3c6999ab	Add mavlink joystick app usage to the docs	2026-05-10 14:50:27 +03:00
Oleg Kalachev	34c6993842	Some fixes in the docs	2026-05-10 02:33:03 +03:00
Oleg Kalachev	b62f2f9427	Rename some wifi parameters for better alphabetical sort	2026-05-09 17:55:55 +03:00
Oleg KalachevandMarina Tikhomirova	7dfef17165	Add Ina Tix' build Co-authored-by: Marina Tikhomirova <Ina.tix@yandex.ru>	2026-05-09 17:49:59 +03:00
Oleg Kalachev	8c8046676b	Simplify port definition in Makefile	2026-05-09 17:14:29 +03:00
Oleg Kalachev	702ec9792e	Some updates in troubleshooting article	2026-05-09 15:57:25 +03:00
Oleg Kalachev	06e2047097	Make motor testing signal 0.2 instead of full power Testing with full power is too dangerous and inconvenient.	2026-05-08 00:53:19 +03:00
Oleg Kalachev	87480476c2	Fix motors pwm frequency for esp32s3 etc in the docs	2026-05-08 00:47:29 +03:00
Oleg Kalachev	68271c508c	Print firmware build date and time in sys command	2026-05-08 00:31:51 +03:00
Oleg Kalachev	e81e84e7fc	Some updates to docs	2026-05-07 20:15:55 +03:00
Oleg Kalachev	5f1a938d4f	Fix imu rotation definition The X axis should be pointing to the mounting holes, not pins side.	2026-05-07 19:54:16 +03:00
Oleg Kalachev	bd270db493	Reduce angle drift by adding level correction to the estimator Leverage a priori knowledge that the drone's average attitude is level. Explanation: https://t.me/opensourcequadcopter/158.	2026-05-05 21:27:47 +03:00
Oleg Kalachev	dbf24ea611	Expose lpf alpha of rate pids to parameters Add parameters: CTL_R_RATE_D_A, CTL_P_RATE_D_A, CTL_Y_RATE_D_A.	2026-05-03 15:04:16 +03:00
Oleg Kalachev	08683d696d	Some updates in the usage doc	2026-05-01 15:26:59 +03:00
Oleg Kalachev	9ca6841558	Exit auto mode when sticks moved only when mode switch is not configured	2026-04-29 15:07:44 +03:00
Oleg Kalachev	28da2d3c8e	Fix in pyflix documentation pyflix@0.14	2026-04-28 20:46:49 +03:00
Oleg Kalachev	c6632ae6e4	Add info on setting flight modes using rc mode switch	2026-04-28 20:43:52 +03:00
Oleg Kalachev	35ca754583	Fix Vector::rotationVectorBetween implementation for parallel vectors	2026-04-28 15:38:52 +03:00
Oleg Kalachev	2ccda03573	Implement motors output desaturation So the drone continues stabilization on max thrust.	2026-04-28 13:23:42 +03:00
Oleg Kalachev	485a39e740	Disable wi-fi power save to improve responsiveness	2026-04-27 16:46:36 +03:00
Oleg Kalachev	9bffe5b52f	Some fixes in docs	2026-04-26 06:05:02 +03:00
Oleg Kalachev	d6a79d6c66	Pass acc data in mG in SCALED_IMU to comply with mavlink standard https://mavlink.io/en/messages/common.html#SCALED_IMU pyflix@0.13	2026-04-24 07:42:39 +03:00
Oleg Kalachev	350a82bfed	Minor fix	2026-04-23 15:34:54 +03:00
Oleg Kalachev	6e439859bc	Move disabling brown-out code to power subsystem	2026-04-23 15:06:07 +03:00
Oleg Kalachev	835b2243e8	Minor fix in sys command String works with printf %s, but actually it's a UB.	2026-04-23 07:25:59 +03:00
Oleg Kalachev	ed4e2d87d1	Fix imu command output Gyro field contained filtered gyro instead of scaled only gyro.	2026-04-23 07:12:25 +03:00
Oleg Kalachev	51cd5fc691	Implement battery voltage monitoring Add power subsystem. Add PWR_VOLT_PIN, PWR_VOLT_SCALE, PWR_VOLT_LPF_A parameters. Support BATTERY_STATUS mavlink messages streaming. Add pw cli command. Add voltage field to pyflix library. pyflix@0.12.	2026-04-22 11:35:37 +03:00