PX4 User Guide (v1.12)

# Modules Reference: Driver

Subcategories:

# adc

Source: drivers/adc/board_adc (opens new window)

# Description

ADC driver.

# Usage

adc <command> [arguments...]
 Commands:
   start
   test
   stop
   status        print status info

# ads1115

Source: drivers/adc/ads1115 (opens new window)

# Usage

ads1115 <command> [arguments...]
 Commands:
   start
     [-I]        Internal I2C bus(es)
     [-X]        External I2C bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
     [-a <val>]  I2C address
                 default: 72
   stop
   status        print status info

# atxxxx

Source: drivers/osd/atxxxx (opens new window)

# Description

OSD driver for the ATXXXX chip that is mounted on the OmnibusF4SD board for example.

It can be enabled with the OSD_ATXXXX_CFG parameter.

# Usage

atxxxx <command> [arguments...]
 Commands:
   start
     [-s]        Internal SPI bus(es)
     [-S]        External SPI bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-c <val>]  chip-select index (for external SPI)
                 default: 1
     [-m <val>]  SPI mode
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
   stop
   status        print status info

# batmon

Source: drivers/smart_battery/batmon (opens new window)

# Description

Driver for SMBUS Communication with BatMon enabled smart-battery Setup/usage information: https://rotoye.com/batmon-tutorial/

# Examples

To start at address 0x0B, on bus 4

batmon start -X -a 11 -b 4

# Usage

batmon <command> [arguments...]
 Commands:
   start
     [-I]        Internal I2C bus(es)
     [-X]        External I2C bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
     [-a <val>]  I2C address
                 default: 11
   man_info      Prints manufacturer info.
   suspend       Suspends the driver from rescheduling the cycle.
   resume        Resumes the driver from suspension.
   stop
   status        print status info

# batt_smbus

Source: drivers/batt_smbus (opens new window)

# Description

Smart battery driver for the BQ40Z50 fuel gauge IC.

# Examples

To write to flash to set parameters. address, number_of_bytes, byte0, ... , byteN

batt_smbus -X write_flash 19069 2 27 0

# Usage

batt_smbus <command> [arguments...]
 Commands:
   start
     [-I]        Internal I2C bus(es)
     [-X]        External I2C bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
     [-a <val>]  I2C address
                 default: 11
   man_info      Prints manufacturer info.
   unseal        Unseals the devices flash memory to enable write_flash
                 commands.
   seal          Seals the devices flash memory to disbale write_flash commands.
   suspend       Suspends the driver from rescheduling the cycle.
   resume        Resumes the driver from suspension.
   write_flash   Writes to flash. The device must first be unsealed with the
                 unseal command.
     [address]   The address to start writing.
     [number of bytes] Number of bytes to send.
     [data[0]...data[n]] One byte of data at a time separated by spaces.
   stop
   status        print status info

# bst

Source: drivers/telemetry/bst (opens new window)

# Usage

bst <command> [arguments...]
 Commands:
   start
     [-I]        Internal I2C bus(es)
     [-X]        External I2C bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
     [-a <val>]  I2C address
                 default: 118
   stop
   status        print status info

# dshot

Source: drivers/dshot (opens new window)

# Description

This is the DShot output driver. It is similar to the fmu driver, and can be used as drop-in replacement to use DShot as ESC communication protocol instead of PWM.

It supports:

  • DShot150, DShot300, DShot600, DShot1200
  • telemetry via separate UART and publishing as esc_status message
  • sending DShot commands via CLI

# Examples

Permanently reverse motor 1:

dshot reverse -m 1
dshot save -m 1

After saving, the reversed direction will be regarded as the normal one. So to reverse again repeat the same commands.

# Usage

dshot <command> [arguments...]
 Commands:
   start         Start the task (without any mode set, use any of the mode_*
                 cmds)
 All of the mode_* commands will start the module if not running already
   mode_gpio
   mode_pwm      Select all available pins as PWM
   mode_pwm14
   mode_pwm12
   mode_pwm8
   mode_pwm6
   mode_pwm5
   mode_pwm5cap1
   mode_pwm4
   mode_pwm4cap1
   mode_pwm4cap2
   mode_pwm3
   mode_pwm3cap1
   mode_pwm2
   mode_pwm2cap2
   mode_pwm1
   telemetry     Enable Telemetry on a UART
     <device>    UART device
   reverse       Reverse motor direction
     [-m <val>]  Motor index (1-based, default=all)
   normal        Normal motor direction
     [-m <val>]  Motor index (1-based, default=all)
   save          Save current settings
     [-m <val>]  Motor index (1-based, default=all)
   3d_on         Enable 3D mode
     [-m <val>]  Motor index (1-based, default=all)
   3d_off        Disable 3D mode
     [-m <val>]  Motor index (1-based, default=all)
   beep1         Send Beep pattern 1
     [-m <val>]  Motor index (1-based, default=all)
   beep2         Send Beep pattern 2
     [-m <val>]  Motor index (1-based, default=all)
   beep3         Send Beep pattern 3
     [-m <val>]  Motor index (1-based, default=all)
   beep4         Send Beep pattern 4
     [-m <val>]  Motor index (1-based, default=all)
   beep5         Send Beep pattern 5
     [-m <val>]  Motor index (1-based, default=all)
   esc_info      Request ESC information
     -m <val>    Motor index (1-based)
   stop
   status        print status info

# fake_gps

Source: examples/fake_gps (opens new window)

# Description

# Usage

fake_gps <command> [arguments...]
 Commands:
   start
   stop
   status        print status info

# fake_imu

Source: examples/fake_imu (opens new window)

# Description

# Usage

fake_imu <command> [arguments...]
 Commands:
   start
   stop
   status        print status info

# fake_magnetometer

Source: examples/fake_magnetometer (opens new window)

# Description

Publish the earth magnetic field as a fake magnetometer (sensor_mag). Requires vehicle_attitude and vehicle_gps_position.

# Usage

fake_magnetometer <command> [arguments...]
 Commands:
   start
   stop
   status        print status info

# gps

Source: drivers/gps (opens new window)

# Description

GPS driver module that handles the communication with the device and publishes the position via uORB. It supports multiple protocols (device vendors) and by default automatically selects the correct one.

The module supports a secondary GPS device, specified via -e parameter. The position will be published on the second uORB topic instance, but it's currently not used by the rest of the system (however the data will be logged, so that it can be used for comparisons).

# Implementation

There is a thread for each device polling for data. The GPS protocol classes are implemented with callbacks so that they can be used in other projects as well (eg. QGroundControl uses them too).

# Examples

Starting 2 GPS devices (the main GPS on /dev/ttyS3 and the secondary on /dev/ttyS4):

gps start -d /dev/ttyS3 -e /dev/ttyS4

Initiate warm restart of GPS device

gps reset warm

# Usage

gps <command> [arguments...]
 Commands:
   start
     [-d <val>]  GPS device
                 values: <file:dev>, default: /dev/ttyS3
     [-b <val>]  Baudrate (can also be p:<param_name>)
                 default: 0
     [-e <val>]  Optional secondary GPS device
                 values: <file:dev>
     [-g <val>]  Baudrate (secondary GPS, can also be p:<param_name>)
                 default: 0
     [-s]        Enable publication of satellite info
     [-i <val>]  GPS interface
                 values: spi|uart, default: uart
     [-j <val>]  secondary GPS interface
                 values: spi|uart, default: uart
     [-p <val>]  GPS Protocol (default=auto select)
                 values: ubx|mtk|ash|eml|fem
   stop
   status        print status info
   reset         Reset GPS device
     cold|warm|hot Specify reset type

# ina226

Source: drivers/power_monitor/ina226 (opens new window)

# Description

Driver for the INA226 power monitor.

Multiple instances of this driver can run simultaneously, if each instance has a separate bus OR I2C address.

For example, one instance can run on Bus 2, address 0x41, and one can run on Bus 2, address 0x43.

If the INA226 module is not powered, then by default, initialization of the driver will fail. To change this, use the -f flag. If this flag is set, then if initialization fails, the driver will keep trying to initialize again every 0.5 seconds. With this flag set, you can plug in a battery after the driver starts, and it will work. Without this flag set, the battery must be plugged in before starting the driver.

# Usage

ina226 <command> [arguments...]
 Commands:
   start
     [-I]        Internal I2C bus(es)
     [-X]        External I2C bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
     [-a <val>]  I2C address
                 default: 65
     [-k]        if initialization (probing) fails, keep retrying periodically
     [-t <val>]  battery index for calibration values (1 or 2)
                 default: 1
   stop
   status        print status info

# iridiumsbd

Source: drivers/telemetry/iridiumsbd (opens new window)

# Description

IridiumSBD driver.

Creates a virtual serial port that another module can use for communication (e.g. mavlink).

# Usage

iridiumsbd <command> [arguments...]
 Commands:
   start
     -d <val>    Serial device
                 values: <file:dev>
     [-v]        Enable verbose output
   test
     [s|read|AT <cmd>] Test command
   stop
   status        print status info

# irlock

Source: drivers/irlock (opens new window)

# Usage

irlock <command> [arguments...]
 Commands:
   start
     [-I]        Internal I2C bus(es)
     [-X]        External I2C bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
     [-a <val>]  I2C address
                 default: 84
   stop
   status        print status info

# linux_pwm_out

Source: drivers/linux_pwm_out (opens new window)

# Description

Linux PWM output driver with board-specific backend implementation.

# Usage

linux_pwm_out <command> [arguments...]
 Commands:
   start
   stop
   status        print status info

# lsm303agr

Source: drivers/magnetometer/lsm303agr (opens new window)

# Usage

lsm303agr <command> [arguments...]
 Commands:
   start
     [-s]        Internal SPI bus(es)
     [-S]        External SPI bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-c <val>]  chip-select index (for external SPI)
                 default: 1
     [-m <val>]  SPI mode
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
     [-R <val>]  Rotation
                 default: 0
   stop
   status        print status info

# newpixel

Source: drivers/lights/neopixel (opens new window)

# Description

This module is responsible for driving interfasing to the Neopixel Serial LED

# Examples

It is typically started with:

neopixel -n 8

To drive all available leds.

# Usage

newpixel <command> [arguments...]
 Commands:
   stop
   status        print status info

# paw3902

Source: drivers/optical_flow/paw3902 (opens new window)

# Usage

paw3902 <command> [arguments...]
 Commands:
   start
     [-s]        Internal SPI bus(es)
     [-S]        External SPI bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-c <val>]  chip-select index (for external SPI)
                 default: 1
     [-m <val>]  SPI mode
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
     [-Y <val>]  custom yaw rotation (degrees)
                 default: 0
   stop
   status        print status info

# pca9685

Source: drivers/pca9685 (opens new window)

# Usage

pca9685 <command> [arguments...]
 Commands:
   start
     [-I]        Internal I2C bus(es)
     [-X]        External I2C bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
     [-a <val>]  I2C address
                 default: 64
   reset
   test          enter test mode
   stop
   status        print status info

# pca9685_pwm_out

Source: drivers/pca9685_pwm_out (opens new window)

# Description

This module is responsible for generate pwm pulse with PCA9685 chip.

It listens on the actuator_controls topics, does the mixing and writes the PWM outputs.

# Implementation

This module depends on ModuleBase and OutputModuleInterface. IIC communication is based on CDev::I2C

# Examples

It is typically started with:

pca9685_pwm_out start -a 64 -b 1

Use the mixer command to load mixer files. mixer load /dev/pwm_outputX etc/mixers/quad_x.main.mix The number X can be acquired by executing pca9685_pwm_out status when this driver is running.

# Usage

pca9685_pwm_out <command> [arguments...]
 Commands:
   start         Start the task
     [-a <val>]  device address on this bus
                 default: 64
     [-b <val>]  bus that pca9685 is connected to
                 default: 1
     [-r <val>]  schedule rate limit
                 default: 400
   stop
   status        print status info

# pcf8583

Source: drivers/rpm/pcf8583 (opens new window)

# Usage

pcf8583 <command> [arguments...]
 Commands:
   start
     [-I]        Internal I2C bus(es)
     [-X]        External I2C bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
     [-a <val>]  I2C address
                 default: 80
   stop
   status        print status info

# pmw3901

Source: drivers/optical_flow/pmw3901 (opens new window)

# Usage

pmw3901 <command> [arguments...]
 Commands:
   start
     [-s]        Internal SPI bus(es)
     [-S]        External SPI bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-c <val>]  chip-select index (for external SPI)
                 default: 1
     [-m <val>]  SPI mode
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
     [-R <val>]  Rotation
                 default: 0
   stop
   status        print status info

# pwm_out

Source: drivers/pwm_out (opens new window)

# Description

This module is responsible for driving the output and reading the input pins. For boards without a separate IO chip (eg. Pixracer), it uses the main channels. On boards with an IO chip (eg. Pixhawk), it uses the AUX channels, and the px4io driver is used for main ones.

It listens on the actuator_controls topics, does the mixing and writes the PWM outputs.

The module is configured via mode_* commands. This defines which of the first N pins the driver should occupy. By using mode_pwm4 for example, pins 5 and 6 can be used by the camera trigger driver or by a PWM rangefinder driver. Alternatively, pwm_out can be started in one of the capture modes, and then drivers can register a capture callback with ioctl calls.

# Implementation

By default the module runs on a work queue with a callback on the uORB actuator_controls topic.

# Examples

It is typically started with:

pwm_out mode_pwm

To drive all available pins.

Capture input (rising and falling edges) and print on the console: start pwm_out in one of the capture modes:

pwm_out mode_pwm3cap1

This will enable capturing on the 4th pin. Then do:

pwm_out test

Use the pwm command for further configurations (PWM rate, levels, ...), and the mixer command to load mixer files.

# Usage

pwm_out <command> [arguments...]
 Commands:
   start         Start the task (without any mode set, use any of the mode_*
                 cmds)
 All of the mode_* commands will start pwm_out if not running already
   mode_gpio
   mode_pwm      Select all available pins as PWM
   mode_pwm14
   mode_pwm12
   mode_pwm8
   mode_pwm6
   mode_pwm5
   mode_pwm5cap1
   mode_pwm4
   mode_pwm4cap1
   mode_pwm4cap2
   mode_pwm3
   mode_pwm3cap1
   mode_pwm2
   mode_pwm2cap2
   mode_pwm1
   sensor_reset  Do a sensor reset (SPI bus)
     [<ms>]      Delay time in ms between reset and re-enabling
   peripheral_reset Reset board peripherals
     [<ms>]      Delay time in ms between reset and re-enabling
   i2c           Configure I2C clock rate
     <bus_id> <rate> Specify the bus id (>=0) and rate in Hz
   test          Test inputs and outputs
   stop
   status        print status info

# pwm_out_sim

Source: drivers/pwm_out_sim (opens new window)

# Description

Driver for simulated PWM outputs.

Its only function is to take actuator_control uORB messages, mix them with any loaded mixer and output the result to the actuator_output uORB topic.

It is used in SITL and HITL.

# Usage

pwm_out_sim <command> [arguments...]
 Commands:
   start         Start the module
     [-m <val>]  Mode
                 values: hil|sim, default: sim
   stop
   status        print status info

# px4flow

Source: drivers/optical_flow/px4flow (opens new window)

# Usage

px4flow <command> [arguments...]
 Commands:
   start
     [-I]        Internal I2C bus(es)
     [-X]        External I2C bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
     [-a <val>]  I2C address
                 default: 66
     [-R <val>]  Rotation (default=downwards)
                 default: 25
   stop
   status        print status info

# rc_input

Source: drivers/rc_input (opens new window)

# Description

This module does the RC input parsing and auto-selecting the method. Supported methods are:

  • PPM
  • SBUS
  • DSM
  • SUMD
  • ST24
  • TBS Crossfire (CRSF)

# Usage

rc_input <command> [arguments...]
 Commands:
   start
     [-d <val>]  RC device
                 values: <file:dev>, default: /dev/ttyS3
   bind          Send a DSM bind command (module must be running)
   stop
   status        print status info

# rgbled

Source: drivers/lights/rgbled_ncp5623c (opens new window)

# Usage

rgbled <command> [arguments...]
 Commands:
   start
     [-I]        Internal I2C bus(es)
     [-X]        External I2C bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
     [-a <val>]  I2C address
                 default: 57
   stop
   status        print status info

# roboclaw

Source: drivers/roboclaw (opens new window)

# Description

This driver communicates over UART with the Roboclaw motor driver (opens new window). It performs two tasks:

  • Control the motors based on the actuator_controls_0 UOrb topic.
  • Read the wheel encoders and publish the raw data in the wheel_encoders UOrb topic

In order to use this driver, the Roboclaw should be put into Packet Serial mode (see the linked documentation), and your flight controller's UART port should be connected to the Roboclaw as shown in the documentation. For Pixhawk 4, use the UART & I2C B port, which corresponds to /dev/ttyS3.

# Implementation

The main loop of this module (Located in RoboClaw.cpp::task_main()) performs 2 tasks:

  1. Write actuator_controls_0 messages to the Roboclaw as they become available
  2. Read encoder data from the Roboclaw at a constant, fixed rate.

Because of the latency of UART, this driver does not write every single actuator_controls_0 message to the Roboclaw immediately. Instead, it is rate limited based on the parameter RBCLW_WRITE_PER.

On startup, this driver will attempt to read the status of the Roboclaw to verify that it is connected. If this fails, the driver terminates immediately.

# Examples

The command to start this driver is:

$ roboclaw start

<device> is the name of the UART port. On the Pixhawk 4, this is /dev/ttyS3. <baud> is te baud rate.

All available commands are:

  • $ roboclaw start <device> <baud>
  • $ roboclaw status
  • $ roboclaw stop

# Usage

roboclaw <command> [arguments...]
 Commands:

# safety_button

Source: drivers/safety_button (opens new window)

# Description

This module is responsible for the safety button. Pressing the safety button 3 times quickly will trigger a GCS pairing request.

# Usage

safety_button <command> [arguments...]
 Commands:
   start
   stop
   status        print status info

# tone_alarm

Source: drivers/tone_alarm (opens new window)

# Description

This module is responsible for the tone alarm.

# Usage

tone_alarm <command> [arguments...]
 Commands:
   start
   stop
   status        print status info

# vmount

Source: modules/vmount (opens new window)

# Description

Mount (Gimbal) control driver. It maps several different input methods (eg. RC or MAVLink) to a configured output (eg. AUX channels or MAVLink).

Documentation how to use it is on the gimbal_control (opens new window) page.

# Implementation

Each method is implemented in its own class, and there is a common base class for inputs and outputs. They are connected via an API, defined by the ControlData data structure. This makes sure that each input method can be used with each output method and new inputs/outputs can be added with minimal effort.

# Examples

Test the output by setting a fixed yaw angle (and the other axes to 0):

vmount stop
vmount test yaw 30

# Usage

vmount <command> [arguments...]
 Commands:
   start
   test          Test the output: set a fixed angle for one axis (vmount must
                 not be running)
     roll|pitch|yaw <angle> Specify an axis and an angle in degrees
   stop
   status        print status info

# voxlpm

Source: drivers/power_monitor/voxlpm (opens new window)

# Usage

voxlpm [arguments...]
   start
     [-I]        Internal I2C bus(es)
     [-X]        External I2C bus(es)
     [-b <val>]  board-specific bus (default=all) (external SPI: n-th bus
                 (default=1))
     [-f <val>]  bus frequency in kHz
     [-q]        quiet startup (no message if no device found)
     [-a <val>]  I2C address
                 default: 68
     [-T <val>]  Type
                 values: VBATT|P5VDC|P12VDC, default: VBATT
     [-k]        if initialization (probing) fails, keep retrying periodically
   stop
   status        print status info