# Holybro Pixhawk 4 (FMUv5) - Discontinued

:::warning PX4 does not manufacture this (or any) autopilot. Contact the [manufacturer](https://holybro.com/) for hardware support or compliance issues. :::

_Pixhawk 4_® is an advanced autopilot designed and made in collaboration with Holybro® and the PX4 team. It is optimized to run PX4 v1.7 and later, and is suitable for academic and commercial developers.

It is based on the [Pixhawk-project](https://pixhawk.org/) **FMUv5** open hardware design and runs PX4 on the [NuttX](https://nuttx.apache.org/) OS.

![](https://4155462212-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-LArEa7z2SPawfl3HpCD%2Fuploads%2Fgit-blob-f28b0534fa40b74cde4c3bda9380398ff5da6c0e%2Fpixhawk4_hero_upright.jpg?alt=media) ![](https://4155462212-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-LArEa7z2SPawfl3HpCD%2Fuploads%2Fgit-blob-11a8acc404ecb5dbf6877d9374bba74d07b1197a%2Fpixhawk4_logo_view.jpg?alt=media)

:::tip This autopilot is [supported]() by the PX4 maintenance and test teams. :::

## Quick Summary

* Main FMU Processor: STM32F765
  * 32 Bit Arm® Cortex®-M7, 216MHz, 2MB memory, 512KB RAM
* IO Processor: STM32F100
  * 32 Bit Arm® Cortex®-M3, 24MHz, 8KB SRAM
* On-board sensors:
  * Accel/Gyro: ICM-20689
  * Accel/Gyro: BMI055 or ICM20602
  * Magnetometer: IST8310
  * Barometer: MS5611
* GPS: u-blox Neo-M8N GPS/GLONASS receiver; integrated magnetometer IST8310
* Interfaces:
  * 8-16 PWM outputs (8 from IO, 8 from FMU)
  * 3 dedicated PWM/Capture inputs on FMU
  * Dedicated R/C input for CPPM
  * Dedicated R/C input for Spektrum / DSM and S.Bus with analog / PWM RSSI input
  * Dedicated S.Bus servo output
  * 5 general purpose serial ports
  * 3 I2C ports
  * 4 SPI buses
  * Up to 2 CANBuses for dual CAN with serial ESC
  * Analog inputs for voltage / current of 2 batteries
* Power System:
  * Power module output: 4.9\~5.5V
  * USB Power Input: 4.75\~5.25V
  * Servo Rail Input: 0\~36V
* Weight and Dimensions:
  * Weight: 15.8g
  * Dimensions: 44x84x12mm
* Other Characteristics:
  * Operating temperature: -40 \~ 85°c

Additional information can be found in the [Pixhawk 4 Technical Data Sheet](https://github.com/PX4/PX4-user_guide/raw/main/assets/flight_controller/pixhawk4/pixhawk4_technical_data_sheet.pdf).

## Where to Buy

Order from [Holybro](https://holybro.com/products/pixhawk-4).

## Connectors

![Pixhawk 4 connectors](https://4155462212-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-LArEa7z2SPawfl3HpCD%2Fuploads%2Fgit-blob-2c2f45ed3e1d699f4694ec116d3e6e5e2e9f8655%2Fpixhawk4-connectors.jpg?alt=media)

:::warning The **DSM/SBUS RC** and **PPM RC** ports are for RC receivers only. These are powered! NEVER connect any servos, power supplies or batteries (or to any connected receiver). :::

## Pinouts

Download _Pixhawk 4_ pinouts from [here](https://cdn.shopify.com/s/files/1/0604/5905/7341/files/Pixhawk4-Pinouts.pdf).

:::note Connector pin assignments are left to right (i.e. Pin 1 is the left-most pin). The exception is the [debug port(s)](#debug_port) (pin 1 is the right-most, as shown below). :::

## Serial Port Mapping

| UART   | Device     | Port                  |
| ------ | ---------- | --------------------- |
| UART1  | /dev/ttyS0 | GPS                   |
| USART2 | /dev/ttyS1 | TELEM1 (flow control) |
| USART3 | /dev/ttyS2 | TELEM2 (flow control) |
| UART4  | /dev/ttyS3 | TELEM4                |
| USART6 | /dev/ttyS4 | RC SBUS               |
| UART7  | /dev/ttyS5 | Debug Console         |
| UART8  | /dev/ttyS6 | PX4IO                 |

## Dimensions

![Pixhawk 4 Dimensions](https://4155462212-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-LArEa7z2SPawfl3HpCD%2Fuploads%2Fgit-blob-85649096c3bdc811f592ea4331850dd05328815c%2Fpixhawk4_dimensions.jpg?alt=media)

## Voltage Ratings

_Pixhawk 4_ can be triple-redundant on the power supply if three power sources are supplied. The three power rails are: **POWER1**, **POWER2** and **USB**.

:::note The output power rails **FMU PWM OUT** and **I/O PWM OUT** (0V to 36V) do not power the flight controller board (and are not powered by it). You must supply power to one of **POWER1**, **POWER2** or **USB** or the board will be unpowered. :::

**Normal Operation Maximum Ratings**

Under these conditions all power sources will be used in this order to power the system:

1. **POWER1** and **POWER2** inputs (4.9V to 5.5V)
2. **USB** input (4.75V to 5.25V)

**Absolute Maximum Ratings**

Under these conditions the system will not draw any power (will not be operational), but will remain intact.

1. **POWER1** and **POWER2** inputs (operational range 4.1V to 5.7V, 0V to 10V undamaged)
2. **USB** input (operational range 4.1V to 5.7V, 0V to 6V undamaged)
3. Servo input: VDD\_SERVO pin of **FMU PWM OUT** and **I/O PWM OUT** (0V to 42V undamaged)

## Assembly/Setup

The [Pixhawk 4 Wiring Quick Start](../../../assembly/quick_start_pixhawk4) provides instructions on how to assemble required/important peripherals including GPS, Power Management Board etc.

## Building Firmware

:::tip Most users will not need to build this firmware! It is pre-built and automatically installed by _QGroundControl_ when appropriate hardware is connected. :::

To [build PX4](../../../development/getting_started/building_px4) for this target:

```
make px4_fmu-v5_default
```

## Debug Port

The [PX4 System Console](../../../development/debug/consoles/system_console) and [SWD interface](../../../development/debug/gdb_debugging/swd_debug) run on the **FMU Debug** port, while the I/O console and SWD interface can be accessed via **I/O Debug** port. In order to access these ports, the user must remove the _Pixhawk 4_ casing.

![Pixhawk 4 Debug Ports](https://4155462212-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-LArEa7z2SPawfl3HpCD%2Fuploads%2Fgit-blob-bbccdee2b1a09602a28c0f205eb125b0bd344aee%2Fpixhawk4_debug_port.jpg?alt=media)

The pinout uses the standard [Pixhawk debug connector pinout](https://github.com/pixhawk/Pixhawk-Standards/blob/master/DS-009%20Pixhawk%20Connector%20Standard.pdf). For wiring information see:

* [System Console > Pixhawk Debug Port](../../../../development/debug/consoles/system_console#pixhawk_debug_port)

## Peripherals

* [Digital Airspeed Sensor](https://store-drotek.com/793-digital-differential-airspeed-sensor-kit-.html)
* [Telemetry Radio Modules](../../peripherals/telemetry)
* [Rangefinders/Distance sensors](../../peripherals/rangefinders)

## Supported Platforms / Airframes

Any multicopter / airplane / rover or boat that can be controlled with normal RC servos or Futaba S-Bus servos. The complete set of supported configurations can be seen in the [Airframes Reference](../../../airframes/airframe_reference).

## Further info

* [Pixhawk 4 Technical Data Sheet](https://github.com/PX4/PX4-user_guide/raw/main/assets/flight_controller/pixhawk4/pixhawk4_technical_data_sheet.pdf)
* [FMUv5 reference design pinout](https://docs.google.com/spreadsheets/d/1-n0__BYDedQrc_2NHqBenG1DNepAgnHpSGglke-QQwY/edit#gid=912976165).
* [Pixhawk 4 Wiring QuickStart](../../../assembly/quick_start_pixhawk4)
* [Pixhawk 4 Pinouts](https://cdn.shopify.com/s/files/1/0604/5905/7341/files/Pixhawk4-Pinouts.pdf) (Holybro)
* [Pixhawk 4 Quick Start Guide](https://cdn.shopify.com/s/files/1/0604/5905/7341/files/Pixhawk4-quickstartguide.pdf) (Holybro)
