PX4 User Guide

# CUAV V5+ Autopilot

V5+® is an advanced autopilot manufactured by CUAV®. It was designed by CUAV® in collaboration with the PX4 team.

The autopilot is recommended for commercial systems integration, but is also suitable for academic research and any other use.

V5+ AutoPilot - hero image

Some of its main features include:

  • Full compatibility with the Pixhawk project FMUv5 design standard and uses the Pixhawk Connector Standard for all external interfaces.
  • More advanced processor, RAM and flash memory than FMU v3, along with more stable and reliable sensors.
  • Firmware-compatible with PX4.
  • Modular design allows users to customize their own carrier board.
  • Built-in vibration dampening system with high performance shock absorption system.
  • Multiple-redundant sensor and power systems for improved flight safety and stability.

Note This flight controller is manufacturer supported.

# 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:

    • Accelerometer/Gyroscope: ICM-20689
    • Accelerometer/Gyroscope: BMI055
    • Magnetometer: IST8310
    • Barometer: MS5611

  • Interfaces:

    • 8-14 PWM outputs (6 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
    • analog / PWM RSSI input
    • S.Bus servo output
    • 5 general purpose serial ports
    • 4 I2C ports
    • 4 SPI buses
    • 2 CANBuses with serial ESC
    • Analog inputs for voltage / current of 2 batteries

  • Power System:

    • Power: 4.3~5.4V
    • USB Input: 4.75~5.25V

  • Weight and Dimensions:

    • Weight: 90g
    • Dimensions: 85.5*42*33mm

  • Other Characteristics:

    • Operating temperature: -20 ~ 80°c（Measured value）

# Purchase

CUAV Aliexpress (International users)

CUAV Taobao (China Mainland users)

Note Autopilot may be purchased with included Neo GPS module

# Connections (Wiring) {#connection}

CUAV V5+ Wiring Quickstart

# Pinouts {#pinouts}

Download V5+ pinouts from here.

# Voltage Ratings

V5+ AutoPilot supports redundant power supplies - up to three sources may be used: Power1, Power2 and USB. You must supply power to at least one of these sources, or the flight controller will be unpowered.

Note On FMUv5 based FMUs with PX4IO module (as is the case for the V5+), the Servo Power Rail is only monitored by the FMU. It is neither powered by, nor provides power to the FMU. However, the pins marked + are all common, and a BEC may be connected to any of the servo pin sets to power the servo power rail.

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 (4.3V to 5.4V)
  2. USB input (4.75V to 5.25V)

# Over Current Protection

The V5+ has over current protection on the 5 Volt Peripheral and 5 Volt high power, which limits the current to 2.5A. The V5+ has short circuit protection.

Warning Up to 2.5 A can be delivered to the connectors listed as pin 1 (although these are only rated at 1 A).

# 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 for this target:

make px4_fmu-v5_default

# Debug Port

The PX4 System Console and SWD interface operate on the FMU Debug port (DSU7). The board does not have an I/O debug interface.

Debug port (DSU7)

The debug port (DSU7) uses a JST BM06B connector and has the following pinout:

Pin Signal Volt
1 (red) 5V+ +5V
2 (blk) DEBUG TX (OUT) +3.3V
3 (blk) DEBUG RX (IN) +3.3V
4 (blk) FMU_SWDIO +3.3V
5 (blk) FMU_SWCLK +3.3V
6 (blk) GND GND

The product package includes a convenient debug cable that can be connected to the DSU7 port. This splits out an FTDI cable for connecting the PX4 System Console to a computer USB port, and SWD pins used for SWD/JTAG debugging. The provided debug cable does not connect to the SWD port Vref pin (1).

CUAV Debug cable

Warning The SWD Vref pin (1) uses 5V as Vref but the CPU is run at 3.3V!

Some JTAG adapters (SEGGER J-Link) will use the Vref voltage to set the voltage on the SWD lines. For direct connection to Segger Jlink we recommended you use the 3.3 Volts from pin 4 of the connector marked DSM/SBUS/RSSI to provide Vtref to the JTAG (i.e. providing 3.3V and NOT 5V).

For more information see Using JTAG for hardware debugging.

# 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 TX is RC input from SBUS_RC connector
UART7 /dev/ttyS5 Debug Console
UART8 /dev/ttyS6 PX4IO

# Peripherals {#optional-hardware}

# 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.

# Notes

# Do not plug Digital or Analog PM onto connectors configured for other type of PM

If you plug an Analog PM into a digital PM connector it will stop all the I2C devices on that bus. Specifically this will stop the GPS's compass due to contention, and may also damage the FMU (longer term).

Similarly, a digital PM plugged into a analog connector will not work, and may also damage/destroy the power module (longer term).

# Compatibility

CUAV adopts some differentiated designs and is incompatible with some hardware, which will be described below.

# GPS not compatible with other devices {#compatibility_gps}

The Neo v2.0 GPS recommended for use with CUAV V5+ and CUAV V5 nano is not fully compatible with other Pixhawk flight controllers (specifically, the buzzer part is not compatible and there may be issues with the safety switch).

The UAVCAN NEO V2 PRO GNSS receiver can also be used, and is compatible with other flight controllers.

# Using JTAG for hardware debugging {#compatibility_jtag}

DSU7 FMU Debug Pin 1 is 5 volts - not the 3.3 volts of the CPU.

Some JTAG use this voltage to set the IO levels when communicating to the target.

For direct connection to Segger Jlink we recommended you use the 3.3 Volts of DSM/SBUS/RSSI pin 4 as Pin 1 on the debug connector (Vtref).

# Known Issues

The issues below refer to the batch number in which they first appear. The batch number is the four-digit production date behind V01 and is displayed on a sticker on the side of the flight controller. For example, the serial number Batch V011904((V01 is the number of V5, 1904 is the production date, that is, the batch number).

# SBUS / DSM / RSSI interface Pin1 unfused {#pin1_unfused}

Warning This is a safety issue.

Please do not connect other equipment (except RC receiver) on SBUS / DSM / RSSI interface - this may lead to equipment damage.

  • Found: Batches V01190904xxxx
  • Fixed: Batches later than V01190904xxxx

# Further Information

← CUAV V5 nano (FMUv5) →