PX4 User Guide
  • Introduction
  • Getting Started
    • Basic Concepts
    • Vehicles/Frames
    • Flight Controllers
    • Sensors
    • Radio Systems
    • Flight Modes
    • Vehicle Status Notifications
      • LED Meanings
      • Tune/Sound Meanings
      • Preflight Checks
    • Payloads & Cameras
    • Flight Reporting
  • Basic Assembly
    • Mounting the Flight Controller
    • Mounting the GPS/Compass
    • Vibration Isolation
    • Cable Wiring
    • CUAV Pixhawk V6X Wiring QuickStart
    • CUAV V5+ Wiring Quickstart
    • CUAV V5 nano Wiring Quickstart
    • Holybro Pixhawk 6C Wiring Quickstart
    • Holybro Pixhawk 6X Wiring Quickstart
    • Holybro Pixhawk 5X Wiring Quickstart
    • Holybro Pixhawk 4 Wiring Quickstart - Discontinued
    • Holybro Pixhawk 4 Mini Wiring Quickstart - Discontinued
    • Holybro Durandal Wiring Quickstart
    • Holybro Pix32 v5 Wiring Quickstart
    • Cube Wiring Quickstart
    • Pixracer Wiring Quickstart
    • mRo (3DR) Pixhawk Wiring Quickstart
  • Standard Configuration
    • Firmware
    • Airframe
    • Sensor Orientation
    • Compass
    • Gyroscope
    • Accelerometer
    • Airspeed
    • Level Horizon Calibration
    • Radio Setup
    • Joystick Setup
    • Flight Modes
    • Battery
    • Safety
      • Failsafe Simulation
    • ESC Calibration
    • Actuators
    • Autotune
  • Vehicle Types & Setup
    • Multicopters
      • Multicopter Config/Tuning
        • MC Filter/Control Latency Tuning
        • MC PID Tuning (Manual/Basic)
        • MC PID Tuning Guide (Manual/Advanced)
        • MC Setpoint Tuning (Trajectory Generator)
          • MC Jerk-limited Type Trajectory
        • Multicopter Racer Setup
      • X500 v2 (Pixhawk 6C)
      • X500 v2 (Pixhawk 5X)
      • X500 (Pixhawk 4)
      • S500 V2 (Pixhawk 4)
      • DJI F450 (CUAV v5+)
      • DJI F450 (CUAV v5 nano)
      • QAV250 (Pixhawk4 Mini) - Discontinued
      • DJI F450 + RTK (Pixhawk 3 Pro)
      • QAV250 (Pixhawk Mini)
      • QAV-R 5" Racer (Pixracer)
      • Omnicopter
    • Planes
      • Fixed Wing Config/Tuning
        • Fixedwing PID Tuning Guide
        • Fixedwing Advanced Tuning Guide
        • Fixedwing Trimming Guide
      • Reptile Dragon 2 (ARK6X)
      • Turbo Timber Evolution (Pixhawk 4 Mini)
      • Wing Wing Z84 (Pixracer)
    • VTOL
      • VTOL Config/Tuning
        • QuadPlane Configuration
        • Back-transition Tuning
        • VTOL w/o Airspeed Sensor
        • VTOL Weather Vane
      • Standard VTOL
        • FunCub QuadPlane (Pixhawk)
        • Ranger QuadPlane (Pixhawk)
        • Falcon Vertigo QuadPlane (Dropix)
      • Tailsitter VTOL
        • Build: TBS Caipiroshka Tailsitter Build (Pixracer)
      • Tiltrotor VTOL
        • Build: Convergence Tiltrotor (Pixfalcon)
    • Airships (experimental)
    • Autogyros (experimental)
      • ThunderFly Auto-G2 (Holybro pix32)
    • Balloons (experimental)
    • Helicopter (experimental)
      • Helicopter Config/Tuning
    • Rovers (experimental)
      • Traxxas Stampede
    • Submarines (experimental)
      • BlueROV2
    • Airframes Reference
  • Flying
    • First Flight Guidelines
    • Flying 101
    • Missions
      • Package Delivery Mission
    • GeoFence
    • Safety Point Planning
    • Flight Modes
      • Position Mode (MC)
      • Altitude Mode (MC)
      • Manual/Stabilized Mode (MC)
      • Acro Mode (MC)
      • Orbit Mode (MC)
      • Position Mode (FW)
      • Altitude Mode (FW)
      • Stabilized Mode (FW)
      • Acro Mode (FW)
      • Manual Mode (FW)
      • Takeoff Mode
      • Land Mode
      • Return Mode
      • Hold Mode
      • Mission Mode
      • Follow Me Mode
      • Offboard Mode
    • Terrain Following/Holding
  • Flight Log Analysis
    • Log Analysis using Flight Review
    • Log Analysis using PlotJuggler
  • Advanced Configuration
    • Finding/Updating Parameters
    • Full Parameter Reference
    • ECL/EKF Overview & Tuning
    • Flight Termination Configuration
    • Bootloader Flashing onto Betaflight Systems
    • Land Detector Configuration
    • Prearm/Arm/Disarm Configuration
    • IMU Factory Calibration
    • Sensor Thermal Compensation
    • Compass Power Compensation
    • Advanced Controller Orientation
    • Static Pressure Buildup
    • Serial Port Configuration
    • MAVLink Telemetry (OSD/GCS)
    • PX4 Ethernet Setup
    • Bootloader Update
  • Hardware (Drones&Parts)
    • Complete Vehicles
      • ModalAI Starling
      • PX4 Vision Kit
      • MindRacer BNF & RTF
        • MindRacer 210
        • NanoMind 110
      • Holybro Kopis 2
      • Bitcraze Crazyflie 2.1
    • Flight Controllers (Autopilots)
      • Pixhawk Series
        • Silicon Errata
      • Pixhawk Standard Autopilots
        • CUAV Pixhawk V6X (FMUv6X)
        • Holybro Pixhawk 6X (FMUv6X)
        • Holybro Pixhawk 6C (FMUv6C)
        • Holybro Pixhawk 6C Mini(FMUv6C)
        • Holybro Pix32 v6 (FMUv6C)
        • Holybro Pixhawk 5X (FMUv5X)
        • Holybro Pixhawk 4 (FMUv5) - Discontinued
        • Holybro Pixhawk 4 Mini (FMUv5) - Discontinued
        • Drotek Pixhawk 3 Pro (FMUv4pro)
        • mRo Pixracer (FMUv4)
        • Hex Cube Black (FMUv3)
        • mRo Pixhawk (FMUv3)
        • Holybro Pixhawk Mini (FMUv3) - Discontinued
      • Manufacturer-Supported Autopilots
        • AirMind MindPX
        • AirMind MindRacer
        • ARK Electronics ARKV6X
        • CUAV X7
        • CUAV Nora
        • CUAV V5+ (FMUv5)
        • CUAV V5 nano (FMUv5)
        • CUAV Pixhack v3 (FMUv3)
        • CubePilot Cube Orange+ (CubePilot)
        • CubePilot Cube Orange (CubePilot)
        • CubePilot Cube Yellow (CubePilot)
        • Holybro Kakute H7v2
        • Holybro Kakute H7mini
        • Holybro Kakute H7
        • Holybro Durandal
        • Holybro Pix32 v5
        • ModalAI Flight Core v1
        • ModalAI VOXL Flight
        • ModalAI VOXL 2
        • mRobotics-X2.1 (FMUv2)
        • mRo Control Zero F7)
        • NXP RDDRONE-FMUK66 FMU
        • Sky-Drones AIRLink
        • SPRacing SPRacingH7EXTREME
        • ThePeach FCC-K1
        • ThePeach FCC-R1
      • Experimental Autopilots
        • BeagleBone Blue
        • Raspberry Pi 2/3 Navio2
        • Raspberry Pi 2/3/4 PilotPi
          • PilotPi with Raspberry Pi OS
          • PilotPi with Ubuntu Server
      • Discontinued Autopilots/Vehicles
        • Drotek Dropix (FMUv2)
        • Omnibus F4 SD
        • BetaFPV Beta75X 2S Brushless Whoop
        • Bitcraze Crazyflie 2.0
        • Aerotenna OcPoC-Zynq Mini
        • CUAV v5
        • Holybro Kakute F7 (Discontinued)
        • Holybro Pixfalcon
        • Holybro pix32 (FMUv2)
        • mRo AUAV-X2
        • 3DR Pixhawk 1
        • Snapdragon Flight
        • Intel® Aero RTF Drone (Discontinued)
      • Pixhawk Autopilot Bus (PAB) & Carriers
        • ARK Electronics Pixhawk Autopilot Bus Carrier
    • Flight Controller Peripherals
      • ADSB/FLARM (Traffic Avoidance)
      • Air Traffic Avoidance: ADSB/FLARM
      • Air Traffic Avoidance: UTM
      • Airspeed Sensors
        • TFSlot Airspeed Sensor
      • Barometers
      • Camera
      • Distance Sensors (Rangefinders)
        • Lightware SFxx Lidar
        • Ainstein US-D1 Standard Radar Altimeter
        • LeddarOne Lidar
        • Benewake TFmini Lidar
        • Lidar-Lite
        • TeraRanger
        • Lanbao PSK-CM8JL65-CC5
        • Avionics Anonymous Laser Altimeter UAVCAN Interface
      • ESCs & Motors
        • PWM ESCs and Servos
        • DShot ESCs
        • OneShot ESCs and Servos
        • DroneCAN ESCs
          • Zubax Telega
          • PX4 Sapog ESC Firmware
            • Holybro Kotleta
            • Zubax Orel
        • VESC
      • TBS Crossfire (CRSF) Telemetry
      • FrSky Telemetry
      • Gimbal (Mount) Configuration
      • GPS/Compass
        • ARK GPS
        • Holybro DroneCAN M8N GPS
        • LOCOSYS Hawk A1 GNSS
        • Hex Here2
        • Holybro M8N & M9N GPS
        • Sky-Drones SmartAP GPS
      • Grippers
        • Servo Gripper
      • Optical Flow
        • ARK Flow
        • PMW3901
        • PX4FLOW (Deprecated)
      • Precision Landing
      • Parachute
      • Power Modules/PDB
        • CUAV HV pm
        • CUAV CAN PMU
        • Holybro PM02
        • Holybro PM07
        • Holybro PM06 V2
        • Holybro PM02D (digital)
        • Holybro PM03D (digital)
        • Pomegranate Systems Power Module
        • Sky-Drones SmartAP PDB
      • Satellite Coms (Iridium/RockBlock)
      • Telemetry Radios
        • SiK Radio
          • RFD900 (SiK) Telemetry Radio
          • HolyBro (SIK) Telemetry Radio
        • Telemetry Wifi
          • ESP8266 WiFi Module
          • ESP32 WiFi Module
          • 3DR Telemetry Wifi (Discontinued)
        • Microhard Serial Telemetry Radio
          • ARK Electron Microhard Serial Telemetry Radio
          • Holybro Microhard P900 Telemetry Radio
        • CUAV P8 Telemetry Radio
        • HolyBro XBP9X - Discontinued
      • RTK GPS
        • ARK RTK GPS
        • RTK GPS Heading with Dual u-blox F9P
        • CUAV C-RTK
        • CUAV C-RTK2 PPK/RTK GNSS
        • CUAV C-RTK 9Ps
        • Femtones MINI2 Receiver
        • Freefly RTK GPS
        • Holybro H-RTK-F9P
        • Holybro H-RTK-M8P
        • Holybro H-RTK Unicore UM982 GPS
        • Locosys Hawk R1
        • Locosys Hawk R2
        • Septentrio AsteRx-RIB
        • Septentrio mosaic-go
        • Trimble MB-Two
        • CubePilot Here+ (Discontined)
      • Remote ID
      • Smart Batteries
        • Rotoye Batmon Battery Smartification Kit
      • Tachometers (Revolution Counters)
        • ThunderFly TFRPM01 Tachometer Sensor
      • I2C Peripherals
        • I2C bus accelerators
        • TFI2CADT01 I2C address translator
      • CAN Peripherals
      • DroneCAN Peripherals
        • PX4 DroneCAN Firmware
        • ARK CANnode
    • Companion Computers
      • Pixhawk + Companion Setup
        • RasPi Pixhawk Companion
      • Companion Computer Peripherals
      • Holybro Pixhawk RPI CM4 Baseboard
      • Auterion Skynode
      • Computer Vision
        • Obstacle Avoidance
        • Safe Landing
        • Collision Prevention
        • Path Planning Interface
        • Motion Capture (MoCap)
        • Visual Inertial Odometry (VIO)
          • Realsense T265 Tracking Camera (VIO)
      • Video Streaming
  • Development
    • Getting Started
      • Recommended Hardware/Setup
      • Toolchain Installation
        • MacOS Setup
        • Ubuntu Setup
        • Windows Setup
        • Visual Studio Code IDE
        • Other/Generic Tools
      • Building the Code
      • Writing your First Application
      • Application/Module Template
    • Concepts
      • PX4 Architecture
      • PX4 Flight Stack Architecture
        • Controller Diagrams
      • Events Interface
      • Flight Modes
      • Flight Tasks
      • Control Allocation
      • PWM limit state machine
      • System Startup
      • SD Card Layout
    • Simulation
      • jMAVSim Simulation
        • Multi-Vehicle Sim with JMAVSim
      • Gazebo Simulation
        • Vehicles
        • Multi-Vehicle Sim
      • Gazebo Classic Simulation
        • Vehicles
        • Worlds
        • Multi-Vehicle Sim
      • FlightGear Simulation
        • FlightGear Vehicles
        • Multi-Vehicle Sim with FlightGear
      • JSBSim Simulation
      • AirSim Simulation
      • Multi-Vehicle Simulation
      • Simulate Failsafes
      • HITL Simulation
      • Simulation-In-Hardware
    • Hardware
      • Flight Controller Reference Design
      • Manufacturer’s Board Support Guide
      • Flight Controller Porting Guide
        • PX4 Board Configuration (kconfig)
        • NuttX Board Porting Guide
      • Serial Port Mapping
      • Airframes
        • Adding a New Airframe
      • Device Drivers
      • Telemetry Radio
        • SiK Radio
      • Sensor and Actuator I/O
        • DroneCAN
        • I2C Bus
        • UART/Serial Ports
          • Port-Configurable Serial Drivers
      • RTK GPS (Integration)
    • Middleware
      • uORB Messaging
      • uORB Graph
      • uORB Message Reference
        • ActionRequest
        • ActuatorArmed
        • ActuatorControlsStatus
        • ActuatorMotors
        • ActuatorOutputs
        • ActuatorServos
        • ActuatorServosTrim
        • ActuatorTest
        • AdcReport
        • Airspeed
        • AirspeedValidated
        • AirspeedWind
        • AutotuneAttitudeControlStatus
        • BatteryStatus
        • ButtonEvent
        • CameraCapture
        • CameraStatus
        • CameraTrigger
        • CellularStatus
        • CollisionConstraints
        • CollisionReport
        • ControlAllocatorStatus
        • Cpuload
        • DebugArray
        • DebugKeyValue
        • DebugValue
        • DebugVect
        • DifferentialPressure
        • DistanceSensor
        • Ekf2Timestamps
        • EscReport
        • EscStatus
        • EstimatorAidSource1d
        • EstimatorAidSource2d
        • EstimatorAidSource3d
        • EstimatorBias
        • EstimatorBias3d
        • EstimatorEventFlags
        • EstimatorGpsStatus
        • EstimatorInnovations
        • EstimatorSelectorStatus
        • EstimatorSensorBias
        • EstimatorStates
        • EstimatorStatus
        • EstimatorStatusFlags
        • Event
        • FailsafeFlags
        • FailureDetectorStatus
        • FollowTarget
        • FollowTargetEstimator
        • FollowTargetStatus
        • GeneratorStatus
        • GeofenceResult
        • GimbalControls
        • GimbalDeviceAttitudeStatus
        • GimbalDeviceInformation
        • GimbalDeviceSetAttitude
        • GimbalManagerInformation
        • GimbalManagerSetAttitude
        • GimbalManagerSetManualControl
        • GimbalManagerStatus
        • GpioConfig
        • GpioIn
        • GpioOut
        • GpioRequest
        • GpsDump
        • GpsInjectData
        • Gripper
        • HealthReport
        • HeaterStatus
        • HomePosition
        • HoverThrustEstimate
        • InputRc
        • InternalCombustionEngineStatus
        • IridiumsbdStatus
        • IrlockReport
        • LandingGear
        • LandingGearWheel
        • LandingTargetInnovations
        • LandingTargetPose
        • LaunchDetectionStatus
        • LedControl
        • LogMessage
        • LoggerStatus
        • MagWorkerData
        • MagnetometerBiasEstimate
        • ManualControlSetpoint
        • ManualControlSwitches
        • MavlinkLog
        • MavlinkTunnel
        • Mission
        • MissionResult
        • ModeCompleted
        • MountOrientation
        • NavigatorMissionItem
        • NormalizedUnsignedSetpoint
        • NpfgStatus
        • ObstacleDistance
        • OffboardControlMode
        • OnboardComputerStatus
        • OrbTest
        • OrbTestLarge
        • OrbTestMedium
        • OrbitStatus
        • ParameterUpdate
        • Ping
        • PositionControllerLandingStatus
        • PositionControllerStatus
        • PositionSetpoint
        • PositionSetpointTriplet
        • PowerButtonState
        • PowerMonitor
        • PpsCapture
        • PwmInput
        • Px4ioStatus
        • QshellReq
        • QshellRetval
        • RadioStatus
        • RateCtrlStatus
        • RcChannels
        • RcParameterMap
        • Rpm
        • RtlTimeEstimate
        • SatelliteInfo
        • SensorAccel
        • SensorAccelFifo
        • SensorBaro
        • SensorCombined
        • SensorCorrection
        • SensorGnssRelative
        • SensorGps
        • SensorGyro
        • SensorGyroFft
        • SensorGyroFifo
        • SensorHygrometer
        • SensorMag
        • SensorOpticalFlow
        • SensorPreflightMag
        • SensorUwb
        • SensorSelection
        • SensorsStatus
        • SensorsStatusImu
        • SystemPower
        • TakeoffStatus
        • TaskStackInfo
        • TecsStatus
        • TelemetryStatus
        • TiltrotorExtraControls
        • TimesyncStatus
        • TrajectoryBezier
        • TrajectorySetpoint
        • TrajectoryWaypoint
        • TransponderReport
        • TuneControl
        • UavcanParameterRequest
        • UavcanParameterValue
        • UlogStream
        • UlogStreamAck
        • UwbDistance
        • UwbGrid
        • VehicleAcceleration
        • VehicleAirData
        • VehicleAngularAccelerationSetpoint
        • VehicleAngularVelocity
        • VehicleAttitude
        • VehicleAttitudeSetpoint
        • VehicleCommand
        • VehicleCommandAck
        • VehicleConstraints
        • VehicleControlMode
        • VehicleGlobalPosition
        • VehicleImu
        • VehicleImuStatus
        • VehicleLandDetected
        • VehicleLocalPosition
        • VehicleLocalPositionSetpoint
        • VehicleMagnetometer
        • VehicleOdometry
        • VehicleOpticalFlow
        • VehicleOpticalFlowVel
        • VehicleRatesSetpoint
        • VehicleRoi
        • VehicleStatus
        • VehicleThrustSetpoint
        • VehicleTorqueSetpoint
        • VehicleTrajectoryBezier
        • VehicleTrajectoryWaypoint
        • VtolVehicleStatus
        • Wind
        • YawEstimatorStatus
      • MAVLink Messaging
      • uXRCE-DDS (PX4-ROS 2/DDS Bridge)
    • Modules & Commands
      • Autotune
      • Commands
      • Communication
      • Controllers
      • Drivers
        • Airspeed Sensor
        • Baro
        • Distance Sensor
        • IMU
        • INS
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        • Rpm Sensor
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      • System
      • Template
    • Debugging/Logging
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        • MAVLink Shell
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      • Debugging with Eclipse
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      • Sending Debug Values
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      • Binary Size Profiling
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      • Flight Log Analysis
      • ULog File Format
    • Tutorials
      • Long-distance Video Streaming
      • Connecting an RC Receiver on Linux
    • Advanced Topics
      • Parameters & Configs
      • Package Delivery Architecture
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        • Motion Capture (VICON, Optitrack, NOKOV)
      • Installing driver for Intel RealSense R200
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Powered by GitBook
On this page
  • ESC Connection Overview
  • Power Connections
  • Fixed Wing / VTOL
  • Multicopter
  • Opto-isolated ESC
  • PX4 Configuration
  • Troubleshooting
  • Ground Connection
  • Power Connection / Opto-isolated ESCs
  • Invalid Minimum Value
  • Timeout
  • Valid Pulse Shape, Voltage and Update Rate
  1. Hardware (Drones&Parts)
  2. Flight Controller Peripherals
  3. ESCs & Motors

PWM ESCs and Servos

This section describes how to connect and power PWM-based brushless motor controllers and servos.

ESC Connection Overview

Each PWM Electronic Speed Controller (ESC) minimally has the following wires:

  • Power VBAT (usually thick and red)

  • Power GND (usually thick and black)

And on the servo plug:

  • PWM signal (usually white or yellow)

  • GND (usually black or brown)

The servo plug may also have a +5V wire (usually red or orange). The purpose of this wire and how it is connected depends on particular ESC and vehicle type.

:::tip In some cases (see below)the +5V line is not needed. Instead of cutting the +5V line you can gently lift of the locking tab of the plastic housing of the servo connector for that pin (e.g. using a cutter blade or small screw driver) and pull the pin out. Isolate it with electrical isolation tape and tape it to the servo cable. This allows you to easily undo the wire later if needed :::

Power Connections

Always connect Power VBAT and GND to the battery, and the PWM signal and GND from the servo plug to the motor.

:::tip There is no setup that does not require signal ground to be connected! :::

The connection to the +5V wire (if present) depends on the ESC/Vehicle.

Fixed Wing / VTOL

On a fixed wing (or VTOL) ESC, the +5V line usually provides the output of a Battery Elimination Circuit (BEC).:

  • This can be connected to the Pixhawk servo rail and used to power servos for flaps, ailerons etc.

    :::note It is unsafe to power servos or ESCs from the autopilot's avionics power supply. This is why Pixhawk series flight controllers do not provide power for the servo rail (the AUX servo rail is unpowered and is limited to 1A). :::

  • As a rule of thumb you should only connect the output of only one BEC to the Pixhawk servo rail. (while it may be possible to connect multiple +5V outputs to the rail, this depends on the ESC model).

Multicopter

On a multicopter, the +5V line might not be present or (if present) may not be connected.

  • Multicopters often do not need servos, and hence do not need to power the Pixhawk servo rail (motors are usually separately powered from a power distribution board).

  • There is no harm (or benefit) in connecting the wire to the servo rail.

  • DJI ESCs typically include this wire, but it is not connected.

Opto-isolated ESC

On an opto-isolated ESC without BEC, the +5V line might need to be connected and powered (in order to provide power to the ESC microcontroller). In this case the wire will normally be connected to the flight controller servo rail, and the servo rail must be powered from an additional BEC.

PX4 Configuration

Troubleshooting

Pixhawk is compatible with all PWM ESCs on the market. If a particular ESC is not operational, it is incorrectly wired up or configured.

Ground Connection

Check that the ground (black wire) of the ESC servo connector is connected to Pixhawk (there is no valid wiring setup that does not have a ground reference).

:::warning It is unsafe to fly without ground connected. This is because for every positive pulse (the ESC signal) there needs to be an adjacent ground return path for a clean signal shape.

The image below shows how noisy the signal becomes if GND is not connected.

Power Connection / Opto-isolated ESCs

If using an opto-isolated ESC that does not provide a BEC / power output, please ensure that the ESC does not need its +5V line powered for the opto-isolator.

See the first section of this page explains for other power connection considerations.

Invalid Minimum Value

Some ESCs need to see a special low value pulse before switching on (to protect users who have the throttle stick in the middle position on power-up).

Timeout

Some ESCs may time out (preventing motor activation) if they have not received a valid low pulse within a few seconds of power on.

Valid Pulse Shape, Voltage and Update Rate

:::note This should not be a problem, but is included for completeness :::

Pixhawk uses active high pulses, as used by all the major brands (Futaba, Spektrum, FrSky).

PWM interfaces are not formally standardised, however, the normal micro controllers all use TTL or CMOS voltage levels. TTL is defined as low < 0.8V and high > 2.0V with some manufacturers using > 2.4V for additional noise margin. CMOS logic is defined with similar voltage levels. 5V levels are never required to successfully switch to an on state.

:::tip Futaba, FrSky and Spektrum receivers output 3.3V or 3.0V voltage levels, as they are well above 2.4V. Pixhawk has adopted this common industry pattern and outputs 3.3V levels on recent boards. :::

PreviousESCs & MotorsNextDShot ESCs

Last updated 1 year ago

PWM motors and servos are configured using the screen in QGroundControl.

After assigning outputs and basic calibration, you may then wish to peform an .

Additional PX4 PWM configuration parameters can be found here: .

:::

PX4 sends a pulse when the vehicle is disarmed, which silences the ESCs when they are disarmed and ensures that ESCs initialise correctly. Appropriate values are determined and set as part of the process (internally these set the per-output parameters and ).

PX4 sends an idle/disarmed pulse right after power on to stop ESCs timing out. Appropriate values are determined and set as part of the process (internally these set the per-output parameters and ).

Actuator Configuration
ESC Calibration
actuator configuration/testing
actuator configuration/testing
PWM without ground
PWM Outputs
PWM_MAIN_DISn
PWM_AUX_DISn
PWM_MAIN_DISn
PWM_AUX_DISn