Pixracer Pro
The Pixracer Pro is the next generation autopilot of mRo’s Pixracer family.
Overview
The Pixracer Pro is the next generation of mRobotics’ family of Pixracer autopilots. It has been designed primarily for the demanding requirements of small multicopters, but of course can be used on planes and other vehicles which require no more than 8 pwm outputs for controlling escs and motors.
Tip
At time of writing the autopilot is still being evolved/improved. The final version may very slightly from the information provided here.
Specifications
- Processor:
- MCU – STM32H743IIK6
- 2MB flash allows full features of ArduPilot to be flashed
- 256KB FRAM – FM25V02-G
- Sensors
- Gyro/Accelerometer: Invensense ICM-20948 / Gyro / Mag
- Gyro/Accelerometer: Invensense ICM-20602 Accel / Gyro
- Gyro/Accelerometer: Bosch BMI088 Accel / Gyro
- Barometer: DPS310
- Power
- Interfaces/Connectivity
- MicroSD card reader
- Micro-C USB
- RGB LED
- GPS (serial + I2C)
- TELEM1/TELEM2
- FrSky Telemetry serial port
- On-Board Buzzer
- 8 Servo/Motor Outputs, 3.3V (default) or 5V level selectable (GPIO 74)
- Connectors: GPS+I2C (USART4), RC-IN/PPM-IN/RSSI/SBus-IN/Spektrum-IN, USART3 (TxD, RxD, CTS, RTS), USART2 (TxD, RxD, CTS, RTS), USART8(FRSky-IN/FRSky-OUT), CAN1, CAN2, SERVO1-SERVO8, USART1/USART7 (TxD, RxD), SPI6, POWER-BRICK (VDD, Voltage, Current, GND).
- Dimensions
Connector pin assignments
Unless noted otherwise all connectors are JST GH
USART2,USART3 (TELEM1/TELEM2)connectors
| PIN |
SIGNAL |
VOLTAGE/TOLERANCE |
| 1 |
+5V |
+5V |
| 2 |
TX |
+3.3V/5V |
| 3 |
RX |
+3.3V/5V |
| 2 |
CTS |
+3.3V |
| 3 |
RTS |
+3.3V/5V |
| 6 |
GND |
GND |
UART1/UART7 connector
| PIN |
SIGNAL |
VOLTAGE/TOLERANCE |
| 1 |
+5V |
+5V |
| 2 |
TX1 |
+3.3V/5V |
| 3 |
RX1 |
+3.3V/5V |
| 4 |
GND |
GND |
| 5 |
+5V |
+5V |
| 6 |
TX7 |
+3.3V/5V |
| 7 |
RX7 |
+3.3V/5V |
| 8 |
GND |
GND |
USART4 (GPS+I2C) connector
| PIN |
SIGNAL |
VOLTAGE/TOLERANCE |
| 1 |
+5V |
+5V |
| 2 |
TX |
+3.3V/5V |
| 3 |
RX |
+3.3V/5V |
| 4 |
SCL |
+3.3V/5V |
| 5 |
SDA |
+3.3V/5V |
| 6 |
GND |
GND |
USART8 (FrSky Telemetry)
| PIN |
SIGNAL |
VOLTAGE/TOLERANCE |
| 1 |
+5V |
+5V |
| 2 |
TX |
+3.3V/5V |
| 3 |
RX |
+3.3V/5V |
| 4 |
GND |
GND |
CAN1 and CAN2 connectors
| PIN |
SIGNAL |
VOLTAGE/TOLERANCE |
| 1 |
+5V |
+5V |
| 2 |
CH |
+3.3V/5V |
| 3 |
CL |
+3.3V/5V |
| 4 |
GND |
GND |
Power connector
| PIN |
SIGNAL |
VOLTAGE/TOLERANCE |
| 1 |
+5V in |
+5V |
| 2 |
+5V in |
+5V |
| 3 |
CURR sense in |
+3.3V/5V |
| 4 |
VOLT sense in |
+3.3V/5V |
| 5 |
GND |
GND |
| 6 |
GND |
GND |
SPI6 connector
| PIN |
SIGNAL |
VOLTAGE/TOLERANCE |
| 1 |
+5V in |
+5V |
| 2 |
MISO |
+3.3V/5V |
| 3 |
SCK |
+3.3V/5V |
| 4 |
CS |
+3.3V/5V |
| 5 |
MOSI |
+3.3V/5V |
| 6 |
GND |
GND |
Default UART order
| Parameter |
Default Protocol** |
Connector |
| SERIAL0 |
console |
USB |
| SERIAL1 |
Telemetry1 |
USART2 (supports CTS and RTS signaling) |
| SERIAL2 |
Telemetry2 |
USART3 (supports CTS and RTS signaling) |
| SERIAL3 |
GPS1 |
UART4 |
| SERIAL4 |
GPS2 |
UART8 (targeted for FrSky Telem, but must change SERIAL4_PROTOCOL) |
| SERIAL5 |
USER |
USART1 |
| SERIAL6 |
USER |
UART7 |
| SERIAL7 |
SLCAN |
USB (second composite USB interface) |
** User may change SERIALx_PROTOCOL as required for application
Dshot capability
All motor/servo outputs are Dshot and PWM capable. However, mixing Dshot and normal PWM operation for outputs is restricted into groups, ie. enabling Dshot for an output in a group requires that ALL outputs in that group be configured and used as Dshot, rather than PWM outputs. The output groups that must be the same (PWM rate or Dshot, when configured as a normal servo/motor output) are: 1/2/3/4, 5/6, and 7/8.
