# RPi PilotPi Shield

Experimental

WARNING

PX4 does not manufacture this (or any) autopilot. Contact the manufacturer for hardware support or compliance issues.

The PilotPi shield is a fully functional solution to run PX4 autopilot directly on Raspberry Pi. It is designed to be a low-cost but highly scalability platform with continuous updates from both Linux and PX4 sides. No proprietary driver is required, as all components have upstream support from RPi and PX4 community. PCB and schematic are open source as well.

PilotPi with RPi 4B

# Quick Summary

  • Supported RPi boards:
    • Raspberry Pi 2B/3B/3B+/4B
  • Supported OS:
    • Raspberry Pi OS
    • Ubuntu Server (armhf/arm64)
  • Accelerometer / Gyro:
    • ICM42688P
  • Magnetometer:
    • IST8310
  • Barometer:
    • MS5611
  • PWM:
    • PCA9685
  • ADC:
    • ADS1115
  • Power:
    • 3~6S battery with built-in voltage sensing.
    • Power the Pi through USB cable
  • Availability: preparing for shipping

# Connectivity

Shield provides:

  • 16x PWM outputting channels
  • GPS connector
  • Telemetry connector
  • External I2C bus connector (Note: conflicts with CSI camera)
  • RC input port (SBUS)
  • 3x ADC channels range 0~5V
  • 2*8 2.54mm unused GPIO connector

Direct accessible from RPi:

  • 4x USB connector
  • CSI connector(Note: conflict with external I2C bus)
  • etc.

PilotPi PowerPart wiring

PilotPi SensorPart wiring

# Pinout

WARNING

It still uses old GH1.25 connectors. Wiring is compatible with Pixhawk 2.4.8

# Connectors

# GPS connector

Mapped to /dev/ttySC0

Pin Signal Volt
1 VCC +5V
2 TX +3v3
3 RX +3v3
4 NC +3v3
5 NC +3v3
6 GND GND

# Telemetry connector

Mapped to /dev/ttySC1

Pin Signal Volt
1 VCC +5V
2 TX +3v3
3 RX +3v3
4 CTS +3v3
5 RTS +3v3
6 GND GND

# External I2C connector

Mapped to /dev/i2c-0

Pin Signal Volt
1 VCC +5V
2 SCL +3v3(pullups)
3 SDA +3v3(pullups)
4 GND GND

# RC & ADC2/3/4

RC is mapped to /dev/ttyAMA0 with signal inverter switch on RX line.

Pin Signal Volt
1 RC +3V3~+5V
2 VCC +5V
3 GND GND
  • ADC1 is internally connected to voltage divider for battery voltage monitoring.
  • ADC2 is left unused.
  • ADC3 can be connected to an analog airspeed sensor.
  • ADC4 has a jumper cap between ADC and VCC, to monitor system voltage level.
Pin Signal Volt
1 ADCx 0V~+5V
2 VCC +5V
3 GND GND

Note

ADC3 & 4 have an alternative VCC source When 'Vref' switch is on, 'VCC' pin is driven by REF5050.

# Unused GPIO available on top of the board

Shield Pin BCM WiringPi RPi Pin
1 3V3 3v3 3V3
2 5V 5V 5V
3 4 7 7
4 14 15 8
5 17 0 11
6 27 2 13
7 22 3 15
8 23 4 16
9 7 11 26
10 5 21 29
11 6 22 31
12 12 26 32
13 13 23 33
14 16 27 36
15 26 25 37
16 GND GND GND

# Switches

# RC Inverter

This switch will decide the signal polarity of RX line: UART_RX = SW xor RC_INPUT

  • On: suitable with SBUS (signal inverted)
  • Off: preserved

# Vref

ADC 3 & 4 will have VCC driven by:

  • Vref output from REF5050 if on
  • 5V pin directly from RPi if off

# Boot Mode

This switch is connected to Pin22(BCM25). System rc script will check its value and decide whether PX4 should start alongside with system booting or not.

  • On: start PX4 automatically
  • Off: don' t start PX4

# Developer Quick Start

Refer to specific instructions for the OS running on your RPi: