Add parameters for mavlink subsystem

System ID, fast telemetry rate, slow telemetry rate.
Remove WIFI_ENABLED ci build
2026-06-28 05:56:44 +00:00 · 2026-01-19 01:28:43 +03:00 · 2026-01-19 01:09:40 +03:00 · 2026-01-19 01:08:29 +03:00 · 2026-01-19 00:53:36 +03:00 · 2026-01-18 21:24:44 +03:00
67 changed files with 539 additions and 1132 deletions
@@ -23,8 +23,6 @@ jobs:
      with:
        name: firmware-binary
        path: flix/build
-    - name: Build firmware for ESP32-C3
-      run: make BOARD=esp32:esp32:esp32c3
    - name: Build firmware for ESP32-S3
      run: make BOARD=esp32:esp32:esp32s3
    - name: Check c_cpp_properties.json
@@ -6,20 +6,34 @@
 				"${workspaceFolder}/flix",
 				"${workspaceFolder}/gazebo",
 				"${workspaceFolder}/tools/**",
-				"~/.arduino15/packages/esp32/hardware/esp32/3.3.6/cores/esp32",
-				"~/.arduino15/packages/esp32/hardware/esp32/3.3.6/libraries/**",
-				"~/.arduino15/packages/esp32/hardware/esp32/3.3.6/variants/d1_mini32",
-				"~/.arduino15/packages/esp32/tools/esp32-libs/3.3.6/include/**",
+				"~/.arduino15/packages/esp32/hardware/esp32/3.2.0/cores/esp32",
+				"~/.arduino15/packages/esp32/hardware/esp32/3.2.0/libraries/**",
+				"~/.arduino15/packages/esp32/hardware/esp32/3.2.0/variants/d1_mini32",
+				"~/.arduino15/packages/esp32/tools/esp32-arduino-libs/idf-release_v5.4-2f7dcd86-v1/esp32/**",
+				"~/.arduino15/packages/esp32/tools/esp32-arduino-libs/idf-release_v5.4-2f7dcd86-v1/esp32/dio_qspi/include",
 				"~/Arduino/libraries/**",
 				"/usr/include/gazebo-11/",
 				"/usr/include/ignition/math6/"
 			],
 			"forcedInclude": [
 				"${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/esp32/3.2.0/cores/esp32/Arduino.h",
+				"~/.arduino15/packages/esp32/hardware/esp32/3.2.0/variants/d1_mini32/pins_arduino.h",
+				"${workspaceFolder}/flix/cli.ino",
+				"${workspaceFolder}/flix/control.ino",
+				"${workspaceFolder}/flix/estimate.ino",
+				"${workspaceFolder}/flix/flix.ino",
+				"${workspaceFolder}/flix/imu.ino",
+				"${workspaceFolder}/flix/led.ino",
+				"${workspaceFolder}/flix/log.ino",
+				"${workspaceFolder}/flix/mavlink.ino",
+				"${workspaceFolder}/flix/motors.ino",
+				"${workspaceFolder}/flix/rc.ino",
+				"${workspaceFolder}/flix/time.ino",
+				"${workspaceFolder}/flix/wifi.ino",
+				"${workspaceFolder}/flix/parameters.ino"
 			],
-			"compilerPath": "~/.arduino15/packages/esp32/tools/esp-x32/2511/bin/xtensa-esp32-elf-g++",
+			"compilerPath": "~/.arduino15/packages/esp32/tools/esp-x32/2411/bin/xtensa-esp32-elf-g++",
 			"cStandard": "c11",
 			"cppStandard": "c++17",
 			"defines": [
@@ -39,20 +53,34 @@
 			"name": "Mac",
 			"includePath": [
 				"${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/esp32/3.2.0/cores/esp32",
+				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.2.0/libraries/**",
+				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.2.0/variants/d1_mini32",
+				"~/Library/Arduino15/packages/esp32/tools/esp32-arduino-libs/idf-release_v5.4-2f7dcd86-v1/esp32/include/**",
+				"~/Library/Arduino15/packages/esp32/tools/esp32-arduino-libs/idf-release_v5.4-2f7dcd86-v1/esp32/dio_qspi/include",
 				"~/Documents/Arduino/libraries/**",
 				"/opt/homebrew/include/gazebo-11/",
 				"/opt/homebrew/include/ignition/math6/"
 			],
 			"forcedInclude": [
 				"${workspaceFolder}/.vscode/intellisense.h",
-				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.3.6/cores/esp32/Arduino.h",
-				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.3.6/variants/d1_mini32/pins_arduino.h"
+				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.2.0/cores/esp32/Arduino.h",
+				"~/Library/Arduino15/packages/esp32/hardware/esp32/3.2.0/variants/d1_mini32/pins_arduino.h",
+				"${workspaceFolder}/flix/flix.ino",
+				"${workspaceFolder}/flix/cli.ino",
+				"${workspaceFolder}/flix/control.ino",
+				"${workspaceFolder}/flix/estimate.ino",
+				"${workspaceFolder}/flix/imu.ino",
+				"${workspaceFolder}/flix/led.ino",
+				"${workspaceFolder}/flix/log.ino",
+				"${workspaceFolder}/flix/mavlink.ino",
+				"${workspaceFolder}/flix/motors.ino",
+				"${workspaceFolder}/flix/rc.ino",
+				"${workspaceFolder}/flix/time.ino",
+				"${workspaceFolder}/flix/wifi.ino",
+				"${workspaceFolder}/flix/parameters.ino"
 			],
-			"compilerPath": "~/Library/Arduino15/packages/esp32/tools/esp-x32/2511/bin/xtensa-esp32-elf-g++",
+			"compilerPath": "~/Library/Arduino15/packages/esp32/tools/esp-x32/2411/bin/xtensa-esp32-elf-g++",
 			"cStandard": "c11",
 			"cppStandard": "c++17",
 			"defines": [
@@ -75,18 +103,32 @@
 				"${workspaceFolder}/flix",
 				"${workspaceFolder}/gazebo",
 				"${workspaceFolder}/tools/**",
-				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.3.6/cores/esp32",
-				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.3.6/libraries/**",
-				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.3.6/variants/d1_mini32",
-				"~/AppData/Local/Arduino15/packages/esp32/tools/esp32-libs/3.3.6/include/**",
+				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.2.0/cores/esp32",
+				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.2.0/libraries/**",
+				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.2.0/variants/d1_mini32",
+				"~/AppData/Local/Arduino15/packages/esp32/tools/esp32-arduino-libs/idf-release_v5.4-2f7dcd86-v1/esp32/**",
+				"~/AppData/Local/Arduino15/packages/esp32/tools/esp32-arduino-libs/idf-release_v5.4-2f7dcd86-v1/esp32/dio_qspi/include",
 				"~/Documents/Arduino/libraries/**"
 			],
 			"forcedInclude": [
 				"${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/esp32/3.2.0/cores/esp32/Arduino.h",
+				"~/AppData/Local/Arduino15/packages/esp32/hardware/esp32/3.2.0/variants/d1_mini32/pins_arduino.h",
+				"${workspaceFolder}/flix/cli.ino",
+				"${workspaceFolder}/flix/control.ino",
+				"${workspaceFolder}/flix/estimate.ino",
+				"${workspaceFolder}/flix/flix.ino",
+				"${workspaceFolder}/flix/imu.ino",
+				"${workspaceFolder}/flix/led.ino",
+				"${workspaceFolder}/flix/log.ino",
+				"${workspaceFolder}/flix/mavlink.ino",
+				"${workspaceFolder}/flix/motors.ino",
+				"${workspaceFolder}/flix/rc.ino",
+				"${workspaceFolder}/flix/time.ino",
+				"${workspaceFolder}/flix/wifi.ino",
+				"${workspaceFolder}/flix/parameters.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-x32/2411/bin/xtensa-esp32-elf-g++.exe",
 			"cStandard": "c11",
 			"cppStandard": "c++17",
 			"defines": [
@@ -1,5 +1,6 @@
 BOARD = esp32:esp32:d1_mini32
-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*))
+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))

 build: .dependencies
 	arduino-cli compile --fqbn $(BOARD) flix
@@ -12,16 +13,12 @@ monitor:

 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
+	arduino-cli core install esp32:esp32@3.2.0 --config-file arduino-cli.yaml
 	arduino-cli lib update-index
 	arduino-cli lib install "FlixPeriph"
-	arduino-cli lib install "MAVLink"@2.0.25
+	arduino-cli lib install "MAVLink"@2.0.16
 	touch .dependencies

-upload_proxy: .dependencies
-	arduino-cli compile --fqbn $(BOARD) tools/espnow-proxy
-	arduino-cli upload --fqbn $(BOARD) -p "$(PORT)" tools/espnow-proxy
-
 gazebo/build cmake: gazebo/CMakeLists.txt
 	mkdir -p gazebo/build
 	cd gazebo/build && cmake ..
@@ -21,8 +21,8 @@
 * Dedicated for education and research.
 * Made from general-purpose components.
 * Simple and clean source code in Arduino (<2k lines firmware).
-* Communication using MAVLink protocol over Wi-Fi or ESP-NOW.
-* Control with USB gamepad, remote control or smartphone.
+* Connectivity using Wi-Fi and MAVLink protocol.
+* Control using USB gamepad, remote control or smartphone.
 * Wireless command line interface and analyzing.
 * Precise simulation with Gazebo.
 * Python library for scripting and automatic flights.
@@ -53,7 +53,7 @@ The simulator is implemented using Gazebo and runs the original Arduino code:

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

-## Documentation articles
+## Documentation

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

 |Type|Part|Image|Quantity|
 |-|-|:-:|:-:|
-|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|
+|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|
 |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 or 65 mm|<img src="docs/img/prop.jpg" 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<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|
+|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|
 |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|
@@ -138,10 +138,10 @@ You can see a user-contributed [variant of complete circuit diagram](https://mir

  |Motor|Position|Direction|Prop type|Motor wires|GPIO|
  |-|-|-|-|-|-|
-  |Motor 0|Rear left|Counter-clockwise|B|Black & White|GPIO12 *(TDI)*|
-  |Motor 1|Rear right|Clockwise|A|Blue & Red|GPIO13 *(TCK)*|
-  |Motor 2|Front right|Counter-clockwise|B|Black & White|GPIO14 *(TMS)*|
-  |Motor 3|Front left|Clockwise|A|Blue & Red|GPIO15 *(TD0)*|
+  |Motor 0|Rear left|Counter-clockwise|B|Black & White|GPIO12 (*TDI*)|
+  |Motor 1|Rear right|Clockwise|A|Blue & Red|GPIO13 (*TCK*)|
+  |Motor 2|Front right|Counter-clockwise|B|Black & White|GPIO14 (*TMS*)|
+  |Motor 3|Front left|Clockwise|A|Blue & Red|GPIO15 (*TD0*)|

  Clockwise motors have blue & red wires and correspond to propeller type A (marked on the propeller).
  Counter-clockwise motors have black & white wires correspond to propeller type B.
@@ -152,16 +152,14 @@ 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)|GPIO4|
+  |Signal (TX)|GPIO4¹|

-* 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.
+*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.*

 ## Resources

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

 ## Disclaimer
@@ -28,8 +28,6 @@ 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]
@@ -43,10 +41,10 @@ Motors connection table:

 |Motor|Position|Direction|Prop type|Motor wires|GPIO|
 |-|-|-|-|-|-|
-|Motor 0|Rear left|Counter-clockwise|B|Black & White|GPIO12 *(TDI)*|
-|Motor 1|Rear right|Clockwise|A|Blue & Red|GPIO13 *(TCK)*|
-|Motor 2|Front right|Counter-clockwise|B|Black & White|GPIO14 *(TMS)*|
-|Motor 3|Front left|Clockwise|A|Blue & Red|GPIO15 *(TD0)*|
+|Motor 0|Rear left|Counter-clockwise|B|Black & White|GPIO12 (*TDI*)|
+|Motor 1|Rear right|Clockwise|A|Blue & Red|GPIO13 (*TCK*)|
+|Motor 2|Front right|Counter-clockwise|B|Black & White|GPIO14 (*TMS*)|
+|Motor 3|Front left|Clockwise|A|Blue & Red|GPIO15 (*TD0*)|

 ## Motors tightening

@@ -110,7 +110,7 @@ float angle = Vector::angleBetween(a, b); // 1.57 (90 градусов)

 #### Скалярное произведение

-Скалярное произведение векторов *(dot product)* — это произведение длин двух векторов на косинус угла между ними. В математике оно обозначается знаком `·` или слитным написанием векторов. Интуитивно, результат скалярного произведения показывает, насколько два вектора *сонаправлены*.
+Скалярное произведение векторов (*dot product*) — это произведение длин двух векторов на косинус угла между ними. В математике оно обозначается знаком `·` или слитным написанием векторов. Интуитивно, результат скалярного произведения показывает, насколько два вектора *сонаправлены*.

 В Flix используется статический метод `Vector::dot()`:

@@ -124,7 +124,7 @@ float dotProduct = Vector::dot(a, b); // 32

 #### Векторное произведение

-Векторное произведение *(cross product)* позволяет найти вектор, перпендикулярный двум другим векторам. В математике оно обозначается знаком `×`, а в прошивке используется статический метод `Vector::cross()`:
+Векторное произведение (*cross product*) позволяет найти вектор, перпендикулярный двум другим векторам. В математике оно обозначается знаком `×`, а в прошивке используется статический метод `Vector::cross()`:

 ```cpp
 Vector a(1, 2, 3);
@@ -144,9 +144,9 @@ Vector crossProduct = Vector::cross(a, b); // -3, 6, -3

 В прошивке углы Эйлера сохраняются в обычный объект `Vector` (хоть и, строго говоря, не являются вектором):

-* Угол по крену *(roll)* — `vector.x`.
-* Угол по тангажу *(pitch)* — `vector.y`.
-* Угол по рысканию *(yaw)* — `vector.z`.
+* Угол по крену (*roll*) — `vector.x`.
+* Угол по тангажу (*pitch*) — `vector.y`.
+* Угол по рысканию (*yaw*) — `vector.z`.

 Особенности углов Эйлера:

@@ -162,8 +162,8 @@ Vector crossProduct = Vector::cross(a, b); // -3, 6, -3

 Помимо углов Эйлера, любую ориентацию в трехмерном пространстве можно представить в виде вращения вокруг некоторой оси на некоторый угол. В геометрии это доказывается, как **теорема вращения Эйлера**. В таком представлении ориентация задается двумя величинами:

-* **Ось вращения** *(axis)* — единичный вектор, определяющий ось вращения.
-* **Угол поворота** *(angle* или *θ)* — угол, на который нужно повернуть объект вокруг этой оси.
+* **Ось вращения** (*axis*) — единичный вектор, определяющий ось вращения.
+* **Угол поворота** (*angle* или *θ*) — угол, на который нужно повернуть объект вокруг этой оси.

 В Flix ось вращения задается объектом `Vector`, а угол поворота — числом типа `float` в радианах:

@@ -177,7 +177,7 @@ float angle = radians(45);

 ### Вектор вращения

-Если умножить вектор *axis* на угол поворота *θ*, то получится **вектор вращения** *(rotation vector)*. Этот вектор играет важную роль в алгоритмах управления ориентацией летательного аппарата.
+Если умножить вектор *axis* на угол поворота *θ*, то получится **вектор вращения** (*rotation vector*). Этот вектор играет важную роль в алгоритмах управления ориентацией летательного аппарата.

 Вектор вращения обладает замечательным свойством: если угловые скорости объекта (в собственной системе координат) в каждый момент времени совпадают с компонентами этого вектора, то за единичное время объект придет к заданной этим вектором ориентации. Это свойство позволяет использовать вектор вращения для управления ориентацией объекта посредством управления угловыми скоростями.

@@ -198,7 +198,7 @@ Vector rotation = radians(45) * Vector(1, 2, 3);
 	<a href="https://github.com/okalachev/flix/blob/master/flix/quaternion.h"><code>quaternion.h</code></a>.<br>
 </div>

-Вектор вращения удобен, но еще удобнее использовать **кватернион**. В Flix кватернионы задаются объектами `Quaternion` из библиотеки `quaternion.h`. Кватернион состоит из четырех значений: *w*, *x*, *y*, *z* и рассчитывается из вектора оси вращения *(axis)* и угла поворота *(θ)* по формуле:
+Вектор вращения удобен, но еще удобнее использовать **кватернион**. В Flix кватернионы задаются объектами `Quaternion` из библиотеки `quaternion.h`. Кватернион состоит из четырех значений: *w*, *x*, *y*, *z* и рассчитывается из вектора оси вращения (*axis*) и угла поворота (*θ*) по формуле:

 \\[ q = \left( \begin{array}{c} w \\\\ x \\\\ y \\\\ z \end{array} \right) = \left( \begin{array}{c} \cos\left(\frac{\theta}{2}\right) \\\\ axis\_x \cdot \sin\left(\frac{\theta}{2}\right) \\\\ axis\_y \cdot \sin\left(\frac{\theta}{2}\right) \\\\ axis\_z \cdot \sin\left(\frac{\theta}{2}\right) \end{array} \right) \\]

@@ -177,7 +177,7 @@ imu.setDLPF(imu.DLPF_MAX);

 ## Калибровка гироскопа

-Как и любое измерительное устройство, гироскоп вносит искажения в измерения. Наиболее простая модель этих искажений делит их на статические смещения *(bias)* и случайный шум *(noise)*:
+Как и любое измерительное устройство, гироскоп вносит искажения в измерения. Наиболее простая модель этих искажений делит их на статические смещения (*bias*) и случайный шум (*noise*):

 \\[ gyro_{xyz}=rates_{xyz}+bias_{xyz}+noise \\]

@@ -67,35 +67,6 @@ 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, two types are supported: `float` and `int`.
-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).
-
-## 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).
@@ -12,25 +12,20 @@ Do the following:

 Do the following:

-* **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 battery voltage**. Use a multimeter to measure the battery voltage. It should be in range of 3.7-4.2 V.
+* **Check if there are some startup errors**. Connect the ESP32 to the computer and check the Serial Monitor output. Use the Reset button to make sure you see the whole ESP32 output.
 * **Check the baudrate is correct**. If you see garbage characters in the Serial Monitor, make sure the baudrate is set to 115200.
-* **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)*.
+* **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 CLI is working**. Perform `help` command in Serial Monitor. You should see the list of available commands. You can also access the CLI 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.
-* **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 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).
 * **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).
@@ -38,10 +33,7 @@ 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">
-
-* **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 controls** using `rc` command. All the controls should change between -1 and 1, and the throttle between 0 and 1.
+* **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, **calibrate the RC**. Type `cr` command in Serial Monitor and follow the instructions.
+* **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.
@@ -20,10 +20,10 @@ You can build and upload the firmware using either **Arduino IDE** (easier for b

 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 3.2.0. 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.
+   * `MAVLink`, version 2.0.16.
 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.
@@ -108,13 +108,13 @@ The drone is configured using parameters. To access and modify them, go to the Q

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

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

 ### Define IMU orientation

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

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

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

 |Orientation|Parameters|Orientation|Parameters|
 |:-:|-|-|-|
-|<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|
+|<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|

 ### Calibrate accelerometer

@@ -134,52 +134,27 @@ Before flight you need to calibrate the accelerometer:
 1. Access the console using QGroundControl (recommended) or Serial Monitor.
 2. Type `ca` command there and follow the instructions.

-### Setup motors
+### Check everything works

-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).
-
-Certain ESP32 models (such as ESP32-S3 and ESP32-C3) support a lower maximum PWM frequency; on these boards the parameter `MOT_PWM_FREQ` should be set to 38000 Hz.
-
-If using brushless motors and 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).
-
-> [!CAUTION]
-> **Remove the props when configuring the motors!** If improperly configured, you may not be able to stop them.
-
-### Battery voltage monitoring
-
-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:
+1. 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.
-   * The `accel bias` and `accel scale` fields should contain calibration parameters (not zeros and ones).
-   * The `gyro bias` field should contain estimated gyro bias (not zeros).
   * The `landed` field should be `1` when the drone is still on the ground and `0` when you lift it up.

 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>

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

-   * `mfr` — rotate front right motor (counter-clockwise).
-   * `mfl` — rotate front left motor (clockwise).
-   * `mrl` — rotate rear left motor (counter-clockwise).
-   * `mrr` — rotate rear right motor (clockwise).
+   * `mfr` — should rotate front right motor (counter-clockwise).
+   * `mfl` — should rotate front left motor (clockwise).
+   * `mrl` — should rotate rear left motor (counter-clockwise).
+   * `mrr` — should rotate rear right motor (clockwise).

-   Make sure rotation directions and propeller types match the following diagram:
+   Rotation diagram:

   <img src="img/motors.svg" width=200>

@@ -192,18 +167,6 @@ There are several ways to control the drone's flight: using **smartphone** (Wi-F

 ### 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`).
@@ -216,13 +179,11 @@ There are several ways to control the drone's flight: using **smartphone** (Wi-F

 ### Control with a remote control

-If using SBUS-connected remote control you need to enable SBUS and calibrate it:
+Before using remote SBUS-connected remote control, you need to 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. 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!
+1. Access the console using QGroundControl (recommended) or Serial Monitor.
+2. Type `cr` command and follow the instructions.
+3. Use the remote control to fly the drone!

 ### Control with a USB remote control

@@ -259,11 +220,11 @@ 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*. 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*).
+Flight mode is changed using mode switch on the remote control or using the command line.

 #### STAB

-In this mode, the drone stabilizes its attitude (orientation). The left stick controls throttle and yaw rate, the right stick controls pitch and roll angles.
+The default mode is *STAB*. In this mode, the drone stabilizes its attitude (orientation). The left stick controls throttle and yaw rate, the right stick controls pitch and roll angles.

 > [!IMPORTANT]
 > The drone doesn't stabilize its position, so slight drift is possible. The pilot should compensate it manually.
@@ -278,9 +239,9 @@ In this mode, the pilot controls the angular rates. This control method is diffi

 #### AUTO

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

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

 ## Wi-Fi configuration

@@ -289,9 +250,12 @@ You can configure the Wi-Fi using parameters and console commands.
 The Wi-Fi mode is chosen using `WIFI_MODE` parameter in QGroundControl or in the console:

 * `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 (may cause additional delays, so generally not recommended).
-* `3` — ESP-NOW mode — the drone uses ESP-NOW protocol for communication.
+* `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.

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

@@ -307,43 +271,6 @@ ap my-flix-ssid mypassword123
 p WIFI_MODE 1
 ```

-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 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.
-
-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*. QGroundControl should connect to the drone using ESP-NOW and begin showing the telemetry.
-
 ## Flight log

 After the flight, you can download the flight log for analysis wirelessly. Use the following command on your computer for that:
@@ -4,49 +4,6 @@ This page contains user-built drones based on the Flix project. Publish your pro

 ---

-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.
-
-<img src="img/user/fanby0ru/1.jpg" height=200> <img src="img/user/fanby0ru/2.jpg" height=200>
-
---
-
-Author: Ivan44 Phalko.<br>
-Description: custom PCB, cusom test bench.<br>
-[Flight validation](https://drive.google.com/file/d/17DNDJ1gPmCmDRAwjedCbJ9RXAyqMqqcX/view?usp=sharing).
-
-<img src="img/user/phalko/1.jpg" height=200> <img src="img/user/phalko/2.jpg" height=200> <img src="img/user/phalko/3.jpg" height=200>
-
---
-
-Author: **Arkadiy "Arky" Matsekh**, Foucault Dynamics, Gold Coast, Australia.<br>
-The drone was built for the University of Queensland industry-led Master's capstone project.
-
-**Flight video:**
-
-<a href="https://drive.google.com/file/d/1NNYSVXBY-w0JjCo07D8-PgnVq3ca9plj/view?usp=sharing"><img height=300 src="img/user/arkymatsekh/video.jpg"></a>
-
-<img src="img/user/arkymatsekh/1.jpg" height=150> <img src="img/user/arkymatsekh/2.jpg" height=150> <img src="img/user/arkymatsekh/3.jpg" height=150>
-
---
-
 Author: [goldarte](https://t.me/goldarte).<br>

 <img src="img/user/goldarte/1.jpg" height=150> <img src="img/user/goldarte/2.jpg" height=150>
@@ -3,33 +3,26 @@

 // Implementation of command line interface

-#include <Arduino.h>
-#include "flix.h"
 #include "pid.h"
 #include "vector.h"
 #include "util.h"
-#include "lpf.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"
@@ -44,11 +37,9 @@ const char* motd =
 "disarm - disarm the drone\n"
 "raw/stab/acro/auto - set mode\n"
 "rc - show RC data\n"
-"pw - show power info\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"
-"espnow <mac> [<key>] - setup ESP-NOW peer\n"
 "mot - show motor output\n"
 "log [dump] - print log header [and data]\n"
 "cr - calibrate RC\n"
@@ -78,7 +69,7 @@ void pause(float duration) {
 	}
 }

-void doCommand(String str, bool echo) {
+void doCommand(String str, bool echo = false) {
 	// parse command
 	String command, arg0, arg1;
 	splitString(str, command, arg0, arg1);
@@ -101,7 +92,7 @@ void doCommand(String str, bool echo) {
 	} 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()));
+			print("%s = %g\n", arg0.c_str(), arg1.toFloat());
 		} else {
 			print("Parameter not found: %s\n", arg0.c_str());
 		}
@@ -142,16 +133,12 @@ void doCommand(String str, bool echo) {
 		print("time: %.1f\n", controlTime);
 		print("mode: %s\n", getModeName());
 		print("armed: %d\n", armed);
-	} else if (command == "pw") {
-		print("Voltage: %.1f V\n", voltage);
 	} else if (command == "wifi") {
 		printWiFiInfo();
 	} else if (command == "ap") {
-		configWiFi(W_AP, arg0.c_str(), arg1.c_str());
+		configWiFi(true, arg0.c_str(), arg1.c_str());
 	} else if (command == "sta") {
-		configWiFi(W_STA, arg0.c_str(), arg1.c_str());
-	} else if (command == "espnow") {
-		configWiFi(W_ESPNOW, arg0.c_str(), arg1.c_str());
+		configWiFi(false, 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]);
@@ -175,7 +162,6 @@ void doCommand(String str, bool echo) {
 		print("Chip: %s\n", ESP.getChipModel());
 		print("Temperature: %.1f °C\n", temperatureRead());
 		print("Free heap: %d\n", ESP.getFreeHeap());
-		print("Firmware: " __DATE__ " " __TIME__ "\n");
 		// Print tasks table
 		print("Num  Task                Stack  Prio  Core  CPU%%\n");
 		int taskCount = uxTaskGetNumberOfTasks();
@@ -186,13 +172,12 @@ void doCommand(String str, bool echo) {
 			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.c_str(), cpuPercentage);
+				systemState[i].usStackHighWaterMark, systemState[i].uxCurrentPriority, core, cpuPercentage);
 		}
 		delete[] systemState;
 #endif
 	} else if (command == "reset") {
 		attitude = Quaternion();
-		gyroBiasFilter.reset();
 	} else if (command == "reboot") {
 		ESP.restart();
 	} else {
@@ -1,55 +0,0 @@
-// Wi-Fi
-#define WIFI_ENABLED 1
-#define WIFI_SSID "flix"
-#define WIFI_PASSWORD "flixwifi"
-#define WIFI_UDP_PORT 14550
-#define WIFI_UDP_REMOTE_PORT 14550
-#define WIFI_UDP_REMOTE_ADDR "255.255.255.255"
-
-// Motors
-#define MOTOR_0_PIN 12 // rear left
-#define MOTOR_1_PIN 13 // rear right
-#define MOTOR_2_PIN 14 // front right
-#define MOTOR_3_PIN 15 // front left
-#define PWM_FREQUENCY 78000
-#define PWM_RESOLUTION 10
-#define PWM_STOP 0
-#define PWM_MIN 0
-#define PWM_MAX 1000000 / PWM_FREQUENCY
-
-// Control
-#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
-
-// Estimation
-#define WEIGHT_ACC 0.003
-#define RATES_LFP_ALPHA 0.2 // cutoff frequency ~ 40 Hz
-
-// MAVLink
-#define SYSTEM_ID 1
-
-// Safety
-#define RC_LOSS_TIMEOUT 1
-#define DESCEND_TIME 10
@@ -3,16 +3,38 @@

 // Flight control

-#include "config.h"
-#include "flix.h"
 #include "vector.h"
 #include "quaternion.h"
 #include "pid.h"
 #include "lpf.h"
 #include "util.h"

-extern const int RAW = 0, ACRO = 1, STAB = 2, AUTO = 3; // flight modes
+#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;

@@ -30,7 +52,6 @@ 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;
-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;
 extern float controlRoll, controlPitch, controlThrottle, controlYaw, controlMode;
@@ -44,9 +65,9 @@ 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[2];
+	if (controlMode < 0.25) mode = STAB;
+	if (controlMode < 0.75) mode = STAB;
+	if (controlMode > 0.75) mode = STAB;

 	if (mode == AUTO) return; // pilot is not effective in AUTO mode

@@ -127,25 +148,12 @@ void controlTorque() {
 	motors[MOTOR_REAR_LEFT] = thrustTarget + torqueTarget.x + torqueTarget.y - torqueTarget.z;
 	motors[MOTOR_REAR_RIGHT] = thrustTarget - torqueTarget.x + torqueTarget.y + torqueTarget.z;

-	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";
@@ -1,10 +1,8 @@
 // Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
 // Repository: https://github.com/okalachev/flix

-// Attitude estimation using gyro and accelerometer
+// Attitude estimation from gyro and accelerometer

-#include "config.h"
-#include "flix.h"
 #include "quaternion.h"
 #include "vector.h"
 #include "lpf.h"
@@ -15,13 +13,11 @@ Quaternion attitude; // estimated attitude
 bool landed;

 float accWeight = 0.003;
-float levelWeight = 0.0002;
 LowPassFilter<Vector> ratesFilter(0.2); // cutoff frequency ~ 40 Hz

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

 void applyGyro() {
@@ -46,12 +42,3 @@ void applyAcc() {
 	// apply correction
 	attitude = Quaternion::rotate(attitude, Quaternion::fromRotationVector(correction));
 }
-
-void applyLevel() {
-	if (landed) return;
-
-	// 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));
-}
@@ -1,95 +0,0 @@
-// Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
-// Repository: https://github.com/okalachev/flix
-
-// All-in-one header file
-
-#pragma once
-
-#include <Arduino.h>
-#include "vector.h"
-#include "quaternion.h"
-
-extern float t, dt;
-extern float loopRate;
-extern float controlRoll, controlPitch, controlYaw, controlThrottle, controlMode;
-extern Vector gyro, acc;
-extern Vector rates;
-extern Quaternion attitude;
-extern bool landed;
-extern int mode;
-extern bool armed;
-extern Quaternion attitudeTarget;
-extern Vector ratesTarget, ratesExtra, torqueTarget;
-extern float thrustTarget;
-extern float motors[4];
-
-void print(const char* format, ...);
-void pause(float duration);
-void doCommand(String str, bool echo = false);
-void handleInput();
-void control();
-void interpretControls();
-void controlAttitude();
-void controlRates();
-void controlTorque();
-void desaturate(float& a, float& b, float& c, float& d);
-const char *getModeName();
-void estimate();
-void applyGyro();
-void applyAcc();
-void applyLevel();
-void setupIMU();
-void configureIMU();
-void readIMU();
-void rotateIMU(Vector& data);
-void calibrateGyroOnce();
-void calibrateAccel();
-void calibrateAccelOnce();
-void printIMUCalibration();
-void printIMUInfo();
-void setupLED();
-void setLED(bool on);
-void blinkLED();
-void prepareLogData();
-void logData();
-void printLogHeader();
-void printLogData();
-void processMavlink();
-void sendMavlink();
-void sendMessage(const void *msg);
-void receiveMavlink();
-void printWiFiInfo();
-void configWiFi(int mode, const char *first, const char *second);
-void handleMavlink(const void *_msg);
-void mavlinkPrint(const char* str);
-void sendMavlinkPrint();
-void setupMotors();
-int getDutyCycle(float value);
-void sendMotors();
-bool motorsActive();
-void testMotor(int n);
-void setupParameters();
-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 syncParameters();
-void printParameters();
-void resetParameters();
-void setupRC();
-bool readRC();
-void normalizeRC();
-void calibrateRC();
-void calibrateRCChannel(int *channel, uint16_t in[16], uint16_t out[16], const char *str);
-void printRCCalibration();
-void setupPower();
-void failsafe();
-void rcLossFailsafe();
-void descend();
-void autoFailsafe();
-void step();
-void computeLoopRate();
-void setupWiFi();
-void sendWiFi(const uint8_t *buf, int len);
-int receiveWiFi(uint8_t *buf, int len);
@@ -3,20 +3,27 @@

 // Main firmware file

-#include "config.h"
 #include "vector.h"
 #include "quaternion.h"
 #include "util.h"
-#include "flix.h"
+
+
+extern float t, dt;
+extern float controlRoll, controlPitch, controlYaw, controlThrottle, controlMode;
+extern Vector gyro, acc;
+extern Vector rates;
+extern Quaternion attitude;
+extern bool landed;
+extern float motors[4];

 void setup() {
 	Serial.begin(115200);
 	print("Initializing flix\n");
+	disableBrownOut();
 	setupParameters();
-	setupPower();
 	setupLED();
-	setLED(true);
 	setupMotors();
+	setLED(true);
 	setupWiFi();
 	setupIMU();
 	setupRC();
@@ -33,7 +40,6 @@ void loop() {
 	sendMotors();
 	handleInput();
 	processMavlink();
-	readVoltage();
 	logData();
 	syncParameters();
 }
@@ -10,7 +10,7 @@
 #include "util.h"

 MPU9250 imu(SPI);
-Vector imuRotation(0, 0, PI / 2); // imu orientation as Euler angles
+Vector imuRotation(0, 0, -PI / 2); // imu orientation as Euler angles

 Vector gyro; // gyroscope output, rad/s
 Vector gyroBias;
@@ -19,8 +19,6 @@ Vector acc; // accelerometer output, m/s/s
 Vector accBias;
 Vector accScale(1, 1, 1);

-LowPassFilter<Vector> gyroBiasFilter(0.001);
-
 void setupIMU() {
 	print("Setup IMU\n");
 	imu.begin();
@@ -52,6 +50,8 @@ void readIMU() {
 void calibrateGyroOnce() {
 	static Delay landedDelay(2);
 	if (!landedDelay.update(landed)) return; // calibrate only if definitely stationary
+
+	static LowPassFilter<Vector> gyroBiasFilter(0.001);
 	gyroBias = gyroBiasFilter.update(gyro);
 }

@@ -121,7 +121,7 @@ void printIMUInfo() {
 	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", gyro.x, gyro.y, gyro.z);
+	print("gyro: %f %f %f\n", rates.x, rates.y, rates.z);
 	print("acc: %f %f %f\n", acc.x, acc.y, acc.z);
 	imu.waitForData();
 	Vector rawGyro, rawAcc;
@@ -3,8 +3,6 @@

 // Board's LED control

-#include <Arduino.h>
-
 #define BLINK_PERIOD 500000

 #ifndef LED_BUILTIN
@@ -3,7 +3,6 @@

 // In-RAM logging

-#include "flix.h"
 #include "vector.h"
 #include "util.h"

@@ -5,8 +5,6 @@

 #pragma once

-#include <Arduino.h>
-
 template <typename T> // Using template to make the filter usable for scalar and vector values
 class LowPassFilter {
 public:
@@ -16,10 +14,15 @@ public:
 	LowPassFilter(float alpha): alpha(alpha) {};

 	T update(const T input) {
-		if (!init) {
-			init = true;
-			return output = input;
+		if (alpha == 1) { // filter disabled
+			return input;
 		}
+
+		if (!initialized) {
+			output = input;
+			initialized = true;
+		}
+
 		return output += alpha * (input - output);
 	}

@@ -28,9 +31,9 @@ public:
 	}

 	void reset() {
-		init = false;
+		initialized = false;
 	}

 private:
-	bool init = false;
+	bool initialized = false;
 };
@@ -3,23 +3,17 @@

 // MAVLink communication

-#include <Arduino.h>
 #include <MAVLink.h>
-#include "config.h"
 #include "util.h"

-extern const int RAW, ACRO, STAB, AUTO;
 extern float controlTime;
-extern float voltage;
-extern uint16_t channels[16];

+bool mavlinkConnected = false;
+String mavlinkPrintBuffer;
 int mavlinkSysId = 1;
 Rate telemetryFast(10);
 Rate telemetrySlow(2);

-bool mavlinkConnected = false;
-static String mavlinkPrintBuffer;
-
 void processMavlink() {
 	sendMavlink();
 	receiveMavlink();
@@ -44,19 +38,12 @@ void sendMavlink() {
 		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);
-
-		uint16_t voltages[] = {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);
-		if (valid(voltage)) sendMessage(&msg);
 	}

 	if (telemetryFast && mavlinkConnected) {
-		const float offset[] = {0, 0, 0, 0};
+		const float zeroQuat[] = {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
+			time, attitude.w, attitude.x, -attitude.y, -attitude.z, rates.x, -rates.y, -rates.z, zeroQuat); // convert to frd
 		sendMessage(&msg);

 		mavlink_msg_rc_channels_raw_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &msg, controlTime * 1000, 0,
@@ -69,7 +56,7 @@ void sendMavlink() {
 		sendMessage(&msg);

 		mavlink_msg_scaled_imu_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &msg, time,
-			acc.x / ONE_G * 1000, -acc.y / ONE_G * 1000, -acc.z / ONE_G * 1000, // convert to frd
+			acc.x * 1000, -acc.y * 1000, -acc.z * 1000, // convert to frd
 			gyro.x * 1000, -gyro.y * 1000, -gyro.z * 1000,
 			0, 0, 0, 0);
 		sendMessage(&msg);
@@ -155,7 +142,7 @@ void handleMavlink(const void *_msg) {
 		// send ack
 		mavlink_message_t msg;
 		mavlink_msg_param_value_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &msg,
-			m.param_id, getParameter(name), MAV_PARAM_TYPE_REAL32, parametersCount(), 0); // index is unknown
+			m.param_id, m.param_value, MAV_PARAM_TYPE_REAL32, parametersCount(), 0); // index is unknown
 		sendMessage(&msg);
 	}

@@ -215,7 +202,6 @@ void handleMavlink(const void *_msg) {
 		armed = motors[0] > 0 || motors[1] > 0 || motors[2] > 0 || motors[3] > 0;
 	}

-	/* TODO:
 	if (msg.msgid == MAVLINK_MSG_ID_LOG_REQUEST_DATA) {
 		mavlink_log_request_data_t m;
 		mavlink_msg_log_request_data_decode(&msg, &m);
@@ -229,7 +215,6 @@ void handleMavlink(const void *_msg) {
 			sendMessage(&msg);
 		}
 	}
-	*/

 	// Handle commands
 	if (msg.msgid == MAVLINK_MSG_ID_COMMAND_LONG) {
@@ -1,64 +0,0 @@
-// Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
-// Repository: https://github.com/okalachev/flix
-
-// PWM control for motors
-
-#include <Arduino.h>
-#include "config.h"
-#include "flix.h"
-#include "util.h"
-
-float motors[4]; // normalized motor thrusts in range [0..1]
-
-int motorPins[4] = {12, 13, 14, 15}; // default pin numbers
-int pwmFrequency = 78000;
-int pwmResolution = 10;
-int pwmStop = 0;
-int pwmMin = 0;
-int pwmMax = -1; // -1 means duty cycle mode
-
-extern 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
-	for (int i = 0; i < 4; i++) {
-		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++) {
-		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;
-		float duty = mapf(pwm, 0, 1000000 / pwmFrequency, 0, (1 << pwmResolution) - 1);
-		return round(duty);
-	} else { // duty cycle mode
-		return round(value * ((1 << pwmResolution) - 1));
-	}
-}
-
-bool motorsActive() {
-	return motors[0] != 0 || motors[1] != 0 || motors[2] != 0 || motors[3] != 0;
-}
-
-void testMotor(int n) {
-	print("Testing motor %d\n", n);
-	motors[n] = 0.2;
-	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);
-	motors[n] = 0;
-	sendMotors();
-	print("Done\n");
-}
@@ -0,0 +1,68 @@
+// Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
+// Repository: https://github.com/okalachev/flix
+
+// Motors output control using MOSFETs
+// In case of using ESCs, change PWM_STOP, PWM_MIN and PWM_MAX to appropriate values in μs, decrease PWM_FREQUENCY (to 400)
+
+#include "util.h"
+
+#define MOTOR_0_PIN 12 // rear left
+#define MOTOR_1_PIN 13 // rear right
+#define MOTOR_2_PIN 14 // front right
+#define MOTOR_3_PIN 15 // front left
+
+#define PWM_FREQUENCY 78000
+#define PWM_RESOLUTION 10
+#define PWM_STOP 0
+#define PWM_MIN 0
+#define PWM_MAX 1000000 / PWM_FREQUENCY
+
+float motors[4]; // normalized motor thrusts in range [0..1]
+
+const int MOTOR_REAR_LEFT = 0;
+const int MOTOR_REAR_RIGHT = 1;
+const int MOTOR_FRONT_RIGHT = 2;
+const int MOTOR_FRONT_LEFT = 3;
+
+void setupMotors() {
+	print("Setup Motors\n");
+
+	// configure pins
+	ledcAttach(MOTOR_0_PIN, PWM_FREQUENCY, PWM_RESOLUTION);
+	ledcAttach(MOTOR_1_PIN, PWM_FREQUENCY, PWM_RESOLUTION);
+	ledcAttach(MOTOR_2_PIN, PWM_FREQUENCY, PWM_RESOLUTION);
+	ledcAttach(MOTOR_3_PIN, PWM_FREQUENCY, PWM_RESOLUTION);
+
+	sendMotors();
+	print("Motors initialized\n");
+}
+
+int getDutyCycle(float value) {
+	value = constrain(value, 0, 1);
+	float pwm = mapf(value, 0, 1, PWM_MIN, PWM_MAX);
+	if (value == 0) pwm = PWM_STOP;
+	float duty = mapf(pwm, 0, 1000000 / PWM_FREQUENCY, 0, (1 << PWM_RESOLUTION) - 1);
+	return round(duty);
+}
+
+void sendMotors() {
+	ledcWrite(MOTOR_0_PIN, getDutyCycle(motors[0]));
+	ledcWrite(MOTOR_1_PIN, getDutyCycle(motors[1]));
+	ledcWrite(MOTOR_2_PIN, getDutyCycle(motors[2]));
+	ledcWrite(MOTOR_3_PIN, getDutyCycle(motors[3]));
+}
+
+bool motorsActive() {
+	return motors[0] != 0 || motors[1] != 0 || motors[2] != 0 || motors[3] != 0;
+}
+
+void testMotor(int n) {
+	print("Testing motor %d\n", n);
+	motors[n] = 1;
+	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);
+	motors[n] = 0;
+	sendMotors();
+	print("Done\n");
+}
@@ -4,63 +4,39 @@
 // Parameters storage in flash memory

 #include <Preferences.h>
-#include "flix.h"
-#include "pid.h"
-#include "lpf.h"
 #include "util.h"

-extern float channelZero[16], channelMax[16];
+extern float channelZero[16];
+extern float channelMax[16];
 extern float rollChannel, pitchChannel, throttleChannel, yawChannel, armedChannel, modeChannel;
-extern float tiltMax;
-extern int flightModes[3];
-extern PID rollPID, pitchPID, yawPID;
-extern PID rollRatePID, pitchRatePID, yawRatePID;
-extern Vector maxRate;
-extern Vector imuRotation;
-extern Vector accBias, accScale;
-extern float accWeight, levelWeight;
-extern LowPassFilter<Vector> gyroBiasFilter, ratesFilter, voltageFilter;
-extern int rcRxPin, voltagePin;
-extern int motorPins[4];
-extern int pwmFrequency, pwmResolution, pwmStop, pwmMin, pwmMax;
-extern int wifiMode, wifiLongRange, udpLocalPort, udpRemotePort, espnowChannel;
-extern int mavlinkSysId;
-extern Rate telemetrySlow, telemetryFast;
-extern float rcLossTimeout, descendTime;
-extern int voltagePin;
-extern float voltageScale;
-extern const int MOTOR_REAR_LEFT, MOTOR_REAR_RIGHT, MOTOR_FRONT_RIGHT, MOTOR_FRONT_LEFT;
+extern int wifiMode, udpLocalPort, udpRemotePort;

 Preferences storage;

 struct Parameter {
-	const char *name; // max length is 15
+	const char *name; // max length is 15 (Preferences key limit)
 	bool integer;
-	union { float *f; int *i; }; // pointer to the variable
+	union { float *f; int *i; }; // pointer to variable
 	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) {};
+	Parameter(const char *name, float *variable) : name(name), integer(false), f(variable) {};
+	Parameter(const char *name, int *variable) : name(name), integer(true), i(variable) {};
 	float getValue() const { return integer ? *i : *f; };
 	void setValue(const float value) { if (integer) *i = value; else *f = value; };
 };

-static Parameter parameters[] = {
+Parameter parameters[] = {
 	// control
 	{"CTL_R_RATE_P", &rollRatePID.p},
 	{"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_D_A", &yawRatePID.lpf.alpha},
 	{"CTL_R_P", &rollPID.p},
 	{"CTL_R_I", &rollPID.i},
 	{"CTL_R_D", &rollPID.d},
@@ -72,9 +48,6 @@ static Parameter parameters[] = {
 	{"CTL_R_RATE_MAX", &maxRate.x},
 	{"CTL_Y_RATE_MAX", &maxRate.z},
 	{"CTL_TILT_MAX", &tiltMax},
-	{"CTL_FLT_MODE_0", &flightModes[0]},
-	{"CTL_FLT_MODE_1", &flightModes[1]},
-	{"CTL_FLT_MODE_2", &flightModes[2]},
 	// imu
 	{"IMU_ROT_ROLL", &imuRotation.x},
 	{"IMU_ROT_PITCH", &imuRotation.y},
@@ -85,23 +58,10 @@ static Parameter parameters[] = {
 	{"IMU_ACC_SCALE_X", &accScale.x},
 	{"IMU_ACC_SCALE_Y", &accScale.y},
 	{"IMU_ACC_SCALE_Z", &accScale.z},
-	{"IMU_GYRO_BIAS_A", &gyroBiasFilter.alpha},
 	// estimate
 	{"EST_ACC_WEIGHT", &accWeight},
-	{"EST_LVL_WEIGHT", &levelWeight},
 	{"EST_RATES_LPF_A", &ratesFilter.alpha},
-	// motors
-	{"MOT_PIN_FL", &motorPins[MOTOR_FRONT_LEFT], setupMotors},
-	{"MOT_PIN_FR", &motorPins[MOTOR_FRONT_RIGHT], setupMotors},
-	{"MOT_PIN_RL", &motorPins[MOTOR_REAR_LEFT], setupMotors},
-	{"MOT_PIN_RR", &motorPins[MOTOR_REAR_RIGHT], setupMotors},
-	{"MOT_PWM_FREQ", &pwmFrequency, setupMotors},
-	{"MOT_PWM_RES", &pwmResolution, setupMotors},
-	{"MOT_PWM_STOP", &pwmStop},
-	{"MOT_PWM_MIN", &pwmMin},
-	{"MOT_PWM_MAX", &pwmMax},
 	// rc
-	{"RC_RX_PIN", &rcRxPin, setupRC},
 	{"RC_ZERO_0", &channelZero[0]},
 	{"RC_ZERO_1", &channelZero[1]},
 	{"RC_ZERO_2", &channelZero[2]},
@@ -125,27 +85,16 @@ static Parameter parameters[] = {
 	{"RC_MODE", &modeChannel},
 	// wifi
 	{"WIFI_MODE", &wifiMode},
-	{"WIFI_PORT_LOC", &udpLocalPort},
-	{"WIFI_PORT_REM", &udpRemotePort},
-	{"WIFI_LONG_RANGE", &wifiLongRange},
-	// espnow
-	{"ESPNOW_CHANNEL", &espnowChannel},
+	{"WIFI_LOC_PORT", &udpLocalPort},
+	{"WIFI_REM_PORT", &udpRemotePort},
 	// mavlink
 	{"MAV_SYS_ID", &mavlinkSysId},
 	{"MAV_RATE_SLOW", &telemetrySlow.rate},
 	{"MAV_RATE_FAST", &telemetryFast.rate},
-	// 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},
 };

 void setupParameters() {
-	print("Setup parameters\n");
-	storage.begin("flix");
+	storage.begin("flix", false);
 	// Read parameters from storage
 	for (auto &parameter : parameters) {
 		if (!storage.isKey(parameter.name)) {
@@ -172,7 +121,7 @@ float getParameter(int index) {

 float getParameter(const char *name) {
 	for (auto &parameter : parameters) {
-		if (strcasecmp(parameter.name, name) == 0) {
+		if (strcmp(parameter.name, name) == 0) {
 			return parameter.getValue();
 		}
 	}
@@ -181,10 +130,9 @@ float getParameter(const char *name) {

 bool setParameter(const char *name, const float value) {
 	for (auto &parameter : parameters) {
-		if (strcasecmp(parameter.name, name) == 0) {
+		if (strcmp(parameter.name, name) == 0) {
 			if (parameter.integer && !isfinite(value)) return false; // can't set integer to NaN or Inf
 			parameter.setValue(value);
-			if (parameter.callback) parameter.callback();
 			return true;
 		}
 	}
@@ -198,7 +146,8 @@ void syncParameters() {

 	for (auto &parameter : parameters) {
 		if (parameter.getValue() == parameter.cache) continue; // no change
-		if (isnan(parameter.getValue()) && isnan(parameter.cache)) continue; // both are NAN
+		if (isnan(parameter.getValue()) && isnan(parameter.cache)) continue; // both are NaN
+		if (isinf(parameter.getValue()) && isinf(parameter.cache)) continue; // both are Inf

 		storage.putFloat(parameter.name, parameter.getValue());
 		parameter.cache = parameter.getValue(); // update cache
@@ -5,8 +5,6 @@

 #pragma once

-#include "Arduino.h"
-#include "flix.h"
 #include "lpf.h"

 class PID {
@@ -1,28 +0,0 @@
-// 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 "lpf.h"
-#include "util.h"
-
-float voltage = NAN;
-LowPassFilter<float> voltageFilter(0.2);
-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);
-}
@@ -5,7 +5,6 @@

 #pragma once

-#include <Arduino.h>
 #include "vector.h"

 class Quaternion : public Printable {
@@ -1,105 +0,0 @@
-// Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
-// Repository: https://github.com/okalachev/flix
-
-// Work with the RC receiver
-
-#include <SBUS.h>
-#include "util.h"
-
-static SBUS rc(Serial1);
-int rcRxPin = -1; // -1 means disabled
-
-uint16_t channels[16]; // raw rc channels
-int channelZero[16]; // calibration zero values
-int channelMax[16]; // calibration max values
-
-float controlRoll, controlPitch, controlYaw, controlThrottle; // pilot's inputs, range [-1, 1]
-float controlMode = NAN;
-float controlTime = NAN; // time of the last controls update
-
-int rollChannel = -1, pitchChannel = -1, throttleChannel = -1, yawChannel = -1, modeChannel = -1; // channel mapping
-
-void setupRC() {
-	if (rcRxPin < 0) return;
-	print("Setup RC\n");
-	rc.begin(rcRxPin);
-}
-
-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;
-}
-
-void normalizeRC() {
-	float controls[16];
-	for (int i = 0; i < 16; i++) {
-		controls[i] = mapf(channels[i], channelZero[i], channelMax[i], 0, 1);
-	}
-	// Update control values
-	controlRoll = rollChannel < 0 ? 0 : controls[rollChannel];
-	controlPitch = pitchChannel < 0 ? 0 : controls[pitchChannel];
-	controlYaw = yawChannel < 0 ? 0 : controls[yawChannel];
-	controlThrottle = throttleChannel < 0 ? 0 : controls[throttleChannel];
-	controlMode = modeChannel < 0 ? NAN : controls[modeChannel]; // mode control is ineffective if not mapped
-}
-
-void calibrateRC() {
-	if (rcRxPin < 0) {
-		print("RC_RX_PIN = %d, set the RC pin!\n", rcRxPin);
-		return;
-	}
-	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, "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();
-}
-
-void calibrateRCChannel(int *channel, uint16_t in[16], uint16_t out[16], const char *str) {
-	print("%s", str);
-	pause(3);
-	for (int i = 0; i < 30; i++) readRC(); // try update 30 times max
-	memcpy(out, channels, sizeof(channels));
-
-	if (channel == NULL) return; // no channel to calibrate
-
-	// Find channel that changed the most between in and out
-	int ch = -1, diff = 0;
-	for (int i = 0; i < 16; i++) {
-		if (abs(out[i] - in[i]) > diff) {
-			ch = i;
-			diff = abs(out[i] - in[i]);
-		}
-	}
-	if (ch >= 0 && diff > 10) { // difference threshold is 10
-		*channel = ch;
-		channelZero[ch] = in[ch];
-		channelMax[ch] = out[ch];
-	} else {
-		*channel = -1;
-	}
-}
-
-void printRCCalibration() {
-	print("Control   Ch     Zero   Max\n");
-	print("Roll      %-7d%-7d%-7d\n", rollChannel, rollChannel < 0 ? 0 : channelZero[rollChannel], rollChannel < 0 ? 0 : channelMax[rollChannel]);
-	print("Pitch     %-7d%-7d%-7d\n", pitchChannel, pitchChannel < 0 ? 0 : channelZero[pitchChannel], pitchChannel < 0 ? 0 : channelMax[pitchChannel]);
-	print("Yaw       %-7d%-7d%-7d\n", yawChannel, yawChannel < 0 ? 0 : channelZero[yawChannel], yawChannel < 0 ? 0 : channelMax[yawChannel]);
-	print("Throttle  %-7d%-7d%-7d\n", throttleChannel, throttleChannel < 0 ? 0 : channelZero[throttleChannel], throttleChannel < 0 ? 0 : channelMax[throttleChannel]);
-	print("Mode      %-7d%-7d%-7d\n", modeChannel, modeChannel < 0 ? 0 : channelZero[modeChannel], modeChannel < 0 ? 0 : channelMax[modeChannel]);
-}
@@ -0,0 +1,99 @@
+// Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
+// Repository: https://github.com/okalachev/flix
+
+// Work with the RC receiver
+
+#include <SBUS.h>
+#include "util.h"
+
+SBUS rc(Serial2);
+
+uint16_t channels[16]; // raw rc channels
+float channelZero[16]; // calibration zero values
+float channelMax[16]; // calibration max values
+
+float controlRoll, controlPitch, controlYaw, controlThrottle; // pilot's inputs, range [-1, 1]
+float controlMode = NAN; //
+float controlTime; // time of the last controls update (0 when no RC)
+
+// Channels mapping (using float to store in parameters):
+float rollChannel = NAN, pitchChannel = NAN, throttleChannel = NAN, yawChannel = NAN, modeChannel = NAN;
+
+void setupRC() {
+	print("Setup RC\n");
+	rc.begin();
+}
+
+bool readRC() {
+	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;
+}
+
+void normalizeRC() {
+	float controls[16];
+	for (int i = 0; i < 16; i++) {
+		controls[i] = mapf(channels[i], channelZero[i], channelMax[i], 0, 1);
+	}
+	// Update control values
+	controlRoll = rollChannel >= 0 ? controls[(int)rollChannel] : 0;
+	controlPitch = pitchChannel >= 0 ? controls[(int)pitchChannel] : 0;
+	controlYaw = yawChannel >= 0 ? controls[(int)yawChannel] : 0;
+	controlThrottle = throttleChannel >= 0 ? controls[(int)throttleChannel] : 0;
+	controlMode = modeChannel >= 0 ? controls[(int)modeChannel] : NAN; // mode switch should not have affect if not set
+}
+
+void calibrateRC() {
+	uint16_t zero[16];
+	uint16_t center[16];
+	uint16_t max[16];
+	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");
+	printRCCalibration();
+}
+
+void calibrateRCChannel(float *channel, uint16_t in[16], uint16_t out[16], const char *str) {
+	print("%s", str);
+	pause(3);
+	for (int i = 0; i < 30; i++) readRC(); // try update 30 times max
+	memcpy(out, channels, sizeof(channels));
+
+	if (channel == NULL) return; // no channel to calibrate
+
+	// Find channel that changed the most between in and out
+	int ch = -1, diff = 0;
+	for (int i = 0; i < 16; i++) {
+		if (abs(out[i] - in[i]) > diff) {
+			ch = i;
+			diff = abs(out[i] - in[i]);
+		}
+	}
+	if (ch >= 0 && diff > 10) { // difference threshold is 10
+		*channel = ch;
+		channelZero[ch] = in[ch];
+		channelMax[ch] = out[ch];
+	} else {
+		*channel = NAN;
+	}
+}
+
+void printRCCalibration() {
+	print("Control   Ch     Zero   Max\n");
+	print("Roll      %-7g%-7g%-7g\n", rollChannel, rollChannel >= 0 ? channelZero[(int)rollChannel] : NAN, rollChannel >= 0 ? channelMax[(int)rollChannel] : NAN);
+	print("Pitch     %-7g%-7g%-7g\n", pitchChannel, pitchChannel >= 0 ? channelZero[(int)pitchChannel] : NAN, pitchChannel >= 0 ? channelMax[(int)pitchChannel] : NAN);
+	print("Yaw       %-7g%-7g%-7g\n", yawChannel, yawChannel >= 0 ? channelZero[(int)yawChannel] : NAN, yawChannel >= 0 ? channelMax[(int)yawChannel] : NAN);
+	print("Throttle  %-7g%-7g%-7g\n", throttleChannel, throttleChannel >= 0 ? channelZero[(int)throttleChannel] : NAN, throttleChannel >= 0 ? channelMax[(int)throttleChannel] : NAN);
+	print("Mode      %-7g%-7g%-7g\n", modeChannel, modeChannel >= 0 ? channelZero[(int)modeChannel] : NAN, modeChannel >= 0 ? channelMax[(int)modeChannel] : NAN);
+}
@@ -3,15 +3,11 @@

 // Fail-safe functions

-#include "config.h"
-#include "flix.h"
-#include "util.h"
+#define RC_LOSS_TIMEOUT 1
+#define DESCEND_TIME 10

 extern float controlTime;
-extern const int AUTO, STAB;
-
-float rcLossTimeout = 1;
-float descendTime = 10;
+extern float controlRoll, controlPitch, controlThrottle, controlYaw;

 void failsafe() {
 	rcLossFailsafe();
@@ -20,8 +16,9 @@ void failsafe() {

 // RC loss failsafe
 void rcLossFailsafe() {
+	if (controlTime == 0) return; // no RC at all
 	if (!armed) return;
-	if (t - controlTime > rcLossTimeout) {
+	if (t - controlTime > RC_LOSS_TIMEOUT) {
 		descend();
 	}
 }
@@ -30,7 +27,7 @@ void rcLossFailsafe() {
 void descend() {
 	mode = AUTO;
 	attitudeTarget = Quaternion();
-	thrustTarget -= dt / descendTime;
+	thrustTarget -= dt / DESCEND_TIME;
 	if (thrustTarget < 0) {
 		thrustTarget = 0;
 		armed = false;
@@ -41,8 +38,8 @@ void descend() {
 void autoFailsafe() {
 	static float roll, pitch, yaw, throttle;
 	if (roll != controlRoll || pitch != controlPitch || yaw != controlYaw || 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
+		// controls changed
+		if (mode == AUTO) mode = STAB; // regain control by the pilot
 	}
 	roll = controlRoll;
 	pitch = controlPitch;
@@ -3,9 +3,6 @@

 // Time related functions

-#include "Arduino.h"
-#include "flix.h"
-
 float t = NAN; // current time, s
 float dt; // time delta with the previous step, s
 float loopRate; // Hz
@@ -6,25 +6,26 @@
 #pragma once

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

 const float ONE_G = 9.80665;
+extern float t;

-inline float mapf(float x, float in_min, float in_max, float out_min, float out_max) {
+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;
 }

-inline bool invalid(float x) {
+bool invalid(float x) {
 	return !isfinite(x);
 }

-inline bool valid(float x) {
+bool valid(float x) {
 	return isfinite(x);
 }

 // Wrap angle to [-PI, PI)
-inline float wrapAngle(float angle) {
+float wrapAngle(float angle) {
 	angle = fmodf(angle, 2 * PI);
 	if (angle > PI) {
 		angle -= 2 * PI;
@@ -34,29 +35,21 @@ inline 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
-inline void splitString(String& str, String& token0, String& token1, String& token2) {
+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, " ");
+	token1 = strtok(NULL, " "); // String(NULL) creates empty string
 	token2 = strtok(NULL, "");
-	if (token1.c_str() == NULL) token1 = "";
-	if (token2.c_str() == NULL) token2 = "";
 }

-// Simplified ESP-NOW Serial without tx buffering and resends
-class ESPNOWSerial : public ESP_NOW_Serial_Class {
-public:
-	using ESP_NOW_Serial_Class::ESP_NOW_Serial_Class;
-	void onSent(bool success) override {} // disable resends
-	size_t write(const uint8_t *data, size_t len) override {
-		return ESP_NOW_Peer::send(data, len); // pure send without buffering
-	}
-};
-
 // Rate limiter
 class Rate {
 public:
@@ -5,8 +5,6 @@

 #pragma once

-#include <Arduino.h>
-
 class Vector : public Printable {
 public:
 	float x, y, z;
@@ -107,23 +105,10 @@ 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.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;
+		if (direction.zero()) {
+			// vectors are opposite, return any perpendicular vector
+			return cross(a, Vector(1, 0, 0));
 		}
 		direction.normalize();
 		float angle = angleBetween(a, b);
@@ -138,5 +123,5 @@ public:
 	}
 };

-inline Vector operator * (const float a, const Vector& b) { return b * a; }
-inline Vector operator + (const float a, const Vector& b) { return b + a; }
+Vector operator * (const float a, const Vector& b) { return b * a; }
+Vector operator + (const float a, const Vector& b) { return b + a; }
@@ -1,132 +0,0 @@
-// Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
-// Repository: https://github.com/okalachev/flix
-
-// Wi-Fi and ESP-NOW communication
-
-#include <WiFi.h>
-#include <WiFiAP.h>
-#include <WiFiUdp.h>
-#include <MacAddress.h>
-#include <ESP32_NOW_Serial.h>
-#include <Preferences.h>
-#include "config.h"
-#include "flix.h"
-#include "util.h"
-
-extern Preferences storage; // use the main preferences storage
-extern bool mavlinkConnected;
-
-extern const int W_DISABLED = 0, W_AP = 1, W_STA = 2, W_ESPNOW = 3;
-int wifiMode = W_AP;
-
-int wifiLongRange = 0;
-int udpLocalPort = 14550;
-int udpRemotePort = 14550;
-static IPAddress udpRemoteIP = "255.255.255.255";
-static WiFiUDP udp;
-
-static ESPNOWSerial espnow(NULL, 0, WIFI_IF_AP);
-static 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());
-		udp.begin(udpLocalPort);
-	} else if (wifiMode == W_STA) {
-		WiFi.begin(storage.getString("WIFI_STA_SSID", "").c_str(), storage.getString("WIFI_STA_PASS", "").c_str());
-		udp.begin(udpLocalPort);
-	} else 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 (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);
-	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 (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());
-	} 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");
-	}
-	print("MAVLink connected: %d\n", mavlinkConnected);
-}
-
-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 {
-		print("Invalid configuration\n");
-		return;
-	}
-	print("✓ Reboot to apply new settings\n");
-}
@@ -0,0 +1,76 @@
+// Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
+// Repository: https://github.com/okalachev/flix
+
+// Wi-Fi connectivity
+
+#include <WiFi.h>
+#include <WiFiAP.h>
+#include <WiFiUdp.h>
+#include "Preferences.h"
+
+extern Preferences storage; // use the main preferences storage
+
+const int W_DISABLED = 0, W_AP = 1, W_STA = 2;
+int wifiMode = W_AP;
+int udpLocalPort = 14550;
+int udpRemotePort = 14550;
+IPAddress udpRemoteIP = "255.255.255.255";
+
+WiFiUDP udp;
+
+void setupWiFi() {
+	print("Setup Wi-Fi\n");
+	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);
+}
+
+void sendWiFi(const uint8_t *buf, int len) {
+	if (WiFi.softAPgetStationNum() == 0 && !WiFi.isConnected()) return;
+	udp.beginPacket(udpRemoteIP, udpRemotePort);
+	udp.write(buf, len);
+	udp.endPacket();
+}
+
+int receiveWiFi(uint8_t *buf, int len) {
+	udp.parsePacket();
+	if (udp.remoteIP()) udpRemoteIP = udp.remoteIP();
+	return udp.read(buf, len);
+}
+
+void printWiFiInfo() {
+	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("Clients: %d\n", WiFi.softAPgetStationNum());
+		print("IP: %s\n", WiFi.softAPIP().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("IP: %s\n", WiFi.localIP().toString().c_str());
+	} else {
+		print("Mode: Disabled\n");
+		return;
+	}
+	print("Remote IP: %s\n", udpRemoteIP.toString().c_str());
+	print("MAVLink connected: %d\n", mavlinkConnected);
+}
+
+void configWiFi(bool ap, const char *ssid, const char *password) {
+	if (ap) {
+		storage.putString("WIFI_AP_SSID", ssid);
+		storage.putString("WIFI_AP_PASS", password);
+	} else {
+		storage.putString("WIFI_STA_SSID", ssid);
+		storage.putString("WIFI_STA_PASS", password);
+	}
+	print("✓ Reboot to apply new settings\n");
+}
@@ -21,8 +21,6 @@
 #define degrees(rad) ((rad)*RAD_TO_DEG)

 #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;
@@ -151,7 +149,7 @@ public:
 	void setRxInvert(bool invert) {};
 };

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

 class EspClass {
 public:
@@ -167,9 +165,6 @@ void delay(uint32_t ms) {

 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; }

 unsigned long __micros;
 unsigned long __resetTime = 0;
@@ -10,23 +10,9 @@ list(APPEND CMAKE_CXX_FLAGS "${GAZEBO_CXX_FLAGS}")

 set(FLIX_SOURCE_DIR ../flix)
 include_directories(${FLIX_SOURCE_DIR})
-set(FLIX_SOURCE_DIR ../flix)
-include_directories(${FLIX_SOURCE_DIR})
-set(FLIX_SOURCES
-  ${FLIX_SOURCE_DIR}/cli.cpp
-  ${FLIX_SOURCE_DIR}/control.cpp
-  ${FLIX_SOURCE_DIR}/estimate.cpp
-  ${FLIX_SOURCE_DIR}/safety.cpp
-  ${FLIX_SOURCE_DIR}/log.cpp
-  ${FLIX_SOURCE_DIR}/mavlink.cpp
-  ${FLIX_SOURCE_DIR}/motors.cpp
-  ${FLIX_SOURCE_DIR}/parameters.cpp
-  ${FLIX_SOURCE_DIR}/rc.cpp
-  ${FLIX_SOURCE_DIR}/time.cpp
-)

 set(CMAKE_BUILD_TYPE RelWithDebInfo)
-add_library(flix SHARED simulator.cpp ${FLIX_SOURCES})
+add_library(flix SHARED simulator.cpp)
 target_link_libraries(flix ${GAZEBO_LIBRARIES} ${SDL2_LIBRARIES})
 target_include_directories(flix PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})
 target_compile_options(flix PRIVATE -Wno-address-of-packed-member) # disable unneeded mavlink warnings
@@ -1,12 +0,0 @@
-// 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; };
-};
@@ -13,7 +13,7 @@ class SBUS {
 public:
 	SBUS(HardwareSerial& bus, const bool inv = true) {};
 	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) {};
+	void begin() {};
 	bool read() { return joystickInit(); };
 	SBUSData data() {
 		SBUSData data;
@@ -9,7 +9,6 @@
 #include "quaternion.h"
 #include "Arduino.h"
 #include "wifi.h"
-#include "lpf.h"

 extern float t, dt;
 extern float controlRoll, controlPitch, controlYaw, controlThrottle, controlMode;
@@ -20,33 +19,28 @@ extern float motors[4];

 Vector gyro, acc, imuRotation;
 Vector accBias, gyroBias, accScale(1, 1, 1);
-LowPassFilter<Vector> gyroBiasFilter(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 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*, uint16_t[16], uint16_t[16], const char*);
+void calibrateRCChannel(float *channel, uint16_t zero[16], uint16_t max[16], const char *str);
 void printRCCalibration();
 void printLogHeader();
 void printLogData();
@@ -58,7 +52,6 @@ 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();
@@ -18,6 +18,18 @@
 #include "Arduino.h"
 #include "flix.h"

+#include "cli.ino"
+#include "control.ino"
+#include "estimate.ino"
+#include "safety.ino"
+#include "log.ino"
+#include "lpf.h"
+#include "mavlink.ino"
+#include "motors.ino"
+#include "parameters.ino"
+#include "rc.ino"
+#include "time.ino"
+
 using ignition::math::Vector3d;
 using namespace gazebo;
 using namespace std;
@@ -60,8 +72,6 @@ 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();

@@ -1,3 +1,4 @@
 // 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) {}
@@ -11,10 +11,9 @@
 #include <sys/poll.h>
 #include <gazebo/gazebo.hh>

-int wifiMode = 1; // mock
-int udpLocalPort = 14580;
-int udpRemotePort = 14550;
-const char *udpRemoteIP = "255.255.255.255";
+#define WIFI_UDP_PORT 14580
+#define WIFI_UDP_REMOTE_PORT 14550
+#define WIFI_UDP_REMOTE_ADDR "255.255.255.255"

 int wifiSocket;

@@ -23,22 +22,22 @@ void setupWiFi() {
 	sockaddr_in addr; // local address
 	addr.sin_family = AF_INET;
 	addr.sin_addr.s_addr = INADDR_ANY;
-	addr.sin_port = htons(udpLocalPort);
+	addr.sin_port = htons(WIFI_UDP_PORT);
 	if (bind(wifiSocket, (sockaddr *)&addr, sizeof(addr))) {
-		gzerr << "Failed to bind WiFi UDP socket on port " << udpLocalPort << std::endl;
+		gzerr << "Failed to bind WiFi UDP socket on port " << WIFI_UDP_PORT << std::endl;
 		return;
 	}
 	int broadcast = 1;
 	setsockopt(wifiSocket, SOL_SOCKET, SO_BROADCAST, &broadcast, sizeof(broadcast)); // enable broadcast
-	gzmsg << "WiFi UDP socket initialized on port " << udpLocalPort << " (remote port " << udpRemotePort << ")" << std::endl;
+	gzmsg << "WiFi UDP socket initialized on port " << WIFI_UDP_PORT << " (remote port " << WIFI_UDP_REMOTE_PORT << ")" << std::endl;
 }

 void sendWiFi(const uint8_t *buf, int len) {
 	if (wifiSocket == 0) setupWiFi();
 	sockaddr_in addr; // remote address
 	addr.sin_family = AF_INET;
-	addr.sin_addr.s_addr = inet_addr(udpRemoteIP);
-	addr.sin_port = htons(udpRemotePort);
+	addr.sin_addr.s_addr = inet_addr(WIFI_UDP_REMOTE_ADDR);
+	addr.sin_port = htons(WIFI_UDP_REMOTE_PORT);
 	sendto(wifiSocket, buf, len, 0, (sockaddr *)&addr, sizeof(addr));
 }

@@ -1,3 +0,0 @@
-# ESPNOW-proxy
-
-Proxy sketch for using ESP-NOW connection with Flix drone.
@@ -1,88 +0,0 @@
-// 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);
-		}
-	}
-}
@@ -10,7 +10,6 @@ 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)
@@ -24,11 +23,11 @@ print('> imu')
 print(flix.cli('imu'))

 print('=== Get parameter...')
-pitch_p = flix.get_param('CTL_P_P')
-print('CTL_P_P = ', pitch_p)
+pitch_p = flix.get_param('PITCH_P')
+print('PITCH_P = ', pitch_p)

 print('=== Set parameter...')
-flix.set_param('CTL_P_P', pitch_p)
+flix.set_param('PITCH_P', pitch_p)

 print('=== Wait for gyro update...')
 print('Gyro: ', flix.wait('gyro'))
@@ -13,7 +13,7 @@ lines = []

 print('Downloading log...')
 count = 0
-dev.write('log dump\n'.encode())
+dev.write('log\n'.encode())
 while True:
    line = dev.readline()
    if not line:
@@ -43,7 +43,6 @@ records = [record for record in records if record[0] != 0]

 print(f'Received records: {len(records)}')

-os.makedirs(f'{DIR}/log', exist_ok=True)
 log = open(f'{DIR}/log/{datetime.datetime.now().isoformat()}.csv', 'wb')
 log.write(header.encode() + b'\n')
 for record in records:
@@ -24,20 +24,19 @@ pip install pyflix
 The API is accessed through the `Flix` class:

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

 ### Telemetry

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

 ```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]
@@ -93,18 +92,17 @@ Full list of events:
 |-----|-----------|----------------|
 |`connected`|Connected to the drone||
 |`disconnected`|Connection is lost||
-|`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)*|
+|`armed`|Armed state update|Armed state (*bool*)|
+|`mode`|Flight mode update|Flight mode (*str*)|
+|`landed`|Landed state update|Landed state (*bool*)|
 |`print`|The drone prints text to the console|Text|
-|`attitude`|Attitude update|Attitude quaternion *(list)*|
-|`attitude_euler`|Attitude update|Euler angles *(list)*|
-|`rates`|Angular rates update|Angular rates *(list)*|
-|`channels`|Raw RC channels update|Raw RC channels *(list)*|
-|`motors`|Motor outputs update|Motor outputs *(list)*|
-|`acc`|Accelerometer update|Accelerometer output *(list)*|
-|`gyro`|Gyroscope update|Gyroscope output *(list)*|
+|`attitude`|Attitude update|Attitude quaternion (*list*)|
+|`attitude_euler`|Attitude update|Euler angles (*list*)|
+|`rates`|Angular rates update|Angular rates (*list*)|
+|`channels`|Raw RC channels update|Raw RC channels (*list*)|
+|`motors`|Motor outputs update|Motor outputs (*list*)|
+|`acc`|Accelerometer update|Accelerometer output (*list*)|
+|`gyro`|Gyroscope update|Gyroscope output (*list*)|
 |`mavlink`|Received MAVLink message|Message object|
 |`mavlink.<message_name>`|Received specific MAVLink message|Message object|
 |`mavlink.<message_id>`|Received specific MAVLink message|Message object|
@@ -119,8 +117,8 @@ Full list of events:
 Get and set firmware parameters using `get_param` and `set_param` methods:

 ```python
-pitch_p = flix.get_param('CTL_P_P')  # get parameter value
-flix.set_param('CTL_P_P', 5)         # set parameter value
+pitch_p = flix.get_param('PITCH_P')  # get parameter value
+flix.set_param('PITCH_P', 5)         # set parameter value
 ```

 Execute console commands using `cli` method. This method returns the command response:
@@ -279,3 +277,7 @@ logger = logging.getLogger('flix')
 logger.setLevel(logging.DEBUG)  # be more verbose
 logger.setLevel(logging.WARNING)  # be less verbose
 ```
+
+## Stability
+
+The library is in development stage. The API is not stable.
@@ -5,7 +5,6 @@

 import os
 import time
-import math
 from queue import Queue, Empty
 from typing import Optional, Callable, List, Dict, Any, Union, Sequence
 import logging
@@ -27,7 +26,6 @@ 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]
@@ -70,7 +68,7 @@ class Flix:
        self._heartbeat_thread.start()
        if wait_connection:
            self.wait('mavlink.HEARTBEAT')
-            time.sleep(0.6) # give some time to receive initial state
+            time.sleep(0.2) # give some time to receive initial state

    def _init_state(self):
        self.attitude = [1, 0, 0, 0]
@@ -140,7 +138,7 @@ class Flix:
        while True:
            try:
                msg: Optional[mavlink.MAVLink_message] = self.connection.recv_match(blocking=True)
-                if msg is None or msg.get_srcSystem() != self.system_id:
+                if msg is None:
                    continue
                self._connected()
                msg_dict = msg.to_dict()
@@ -187,16 +185,11 @@ class Flix:
            self._trigger('motors', self.motors)

        if isinstance(msg, mavlink.MAVLink_scaled_imu_message):
-            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.acc = self._mavlink_to_flu([msg.xacc / 1000, msg.yacc / 1000, msg.zacc / 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')
@@ -1,6 +1,6 @@
 [project]
 name = "pyflix"
-version = "0.15"
+version = "0.11"
 description = "Python API for Flix drone"
 authors = [{ name="Oleg Kalachev", email="okalachev@gmail.com" }]
 license = "MIT"
Author	SHA1	Message	Date
Oleg Kalachev	8a12d1fa70	Add parameters for mavlink subsystem System ID, fast telemetry rate, slow telemetry rate.	2026-01-19 01:28:43 +03:00
Oleg Kalachev	a7cd6473fd	Remove WIFI_ENABLED ci build	2026-01-19 01:09:40 +03:00
Oleg Kalachev	5960e85a74	Don't send param_ack if parameter is not set	2026-01-19 01:08:29 +03:00
Oleg Kalachev	cef1834ea3	Implement wi-fi configuration Add console commands to setup wi-fi Add parameter for choosing between STA and AP mode. Add parameter for udp ports. Remove WIFI_ENABLED macro.	2026-01-19 00:53:36 +03:00
Oleg Kalachev	6548ae5708	Add possibility to use int variables as parameters In addition to floats.	2026-01-18 21:24:44 +03:00