Pixhawk 6C 6C Mini Flight Controller¶
Pixhawk6C is the latest update to the successful family of Pixhawk® autopilots made by Holybro, featuring STM32H7 cpus, vibration isolation of IMUs, redundant IMUs, and IMU heating. It comes in two form factors. The 6C Mini reduces the size and has a built-in PWM motor/servo header, at the expense of a bit fewer ports.
Where To Buy¶
The Pixhawk6 autopilots are sold by Holybro
Features of Pixhawk6 Series¶
(click table below to expand)
UART Mapping¶
SERIAL0 -> USB
SERIAL1 -> UART7 (Telem1) RTS/CTS pins
SERIAL2 -> UART5 (Telem2) RTS/CTS pins
SERIAL3 -> USART1 (GPS1)
SERIAL4 -> UART8 (GPS2)
SERIAL5 -> USART2 (Telem3) RTS/CTS pins (not included on 6C Mini)
SERIAL6 -> USART3 (USER) (Debug p)
SERIAL7 -> USB (can be used for SLCAN with protocol change)
RC Input¶
The RCIN pin, which by default is mapped to a timer input, can be used for all ArduPilot supported receiver protocols, except CRSF/ELRS and SRXL2 which require a true UART connection. However, FPort, when connected in this manner, will only provide RC without telemetry.
To allow CRSF and embedded telemetry available in Fport, CRSF, and SRXL2 receivers, a full UART, such as SERIAL5 (UART3) would need to be used for receiver connections. Below are setups using Serial6. For the 6C Mini, SERIAL1 - SERIAL4 would need to be used.
SERIAL5_PROTOCOL should be set to “23”.
FPort would require SERIAL5_OPTIONS be set to “15”.
CRSF would require SERIAL5_OPTIONS be set to “0”.
SRXL2 would require SERIAL5_OPTIONS be set to “4” and connects only the TX pin.
Any UART can be used for RC system connections in ArduPilot also, and is compatible with all protocols except PPM. See Radio Control Systems for details.
PWM Output¶
The Pixhawk6C supports up to 16 PWM outputs. All 16 outputs support all normal PWM output formats. All FMU outputs (marked “FMU PWM Output”) also support DShot.
The 8 FMU PWM outputs are in 4 groups:
PWM 1, 2, 3 and 4 in group1
PWM 5 and 6 in group2
PWM 7 and 8 in group3 (not 6C Mini)
FMU outputs within the same group need to use the same output rate and protocol. If any output in a group uses DShot then all channels in that group need to use DShot.
Note
to use BDShot capability on outputs 1-8, use the firmware in the “Pixhawk6C-bdshot” folder on the Firmware Server
Battery Monitoring¶
The board has 2 dedicated power monitor ports with a 6 pin connector. The Pixhawk6C uses analog power monitors on these ports.
BATT_MONITOR = 4
BATT_VOLT_PIN = 8
BATT_CURR_PIN = 4
BATT_VOLT_MULT = 18.182
BATT_AMP_PERVLT = 36.364
BATT2_VOLT_PIN = 5
BATT2_CURR_PIN = 14
BATT2_VOLT_MULT = 18.182
BATT2_AMP_PERVLT = 36.364
Compass¶
The Pixhawk6C/Mini has a built-in compass. Due to potential interference, the autopilot is usually used with an external I2C compass as part of a GPS/Compass combination.
GPIOs¶
The FMU PWM outputs can be used as GPIOs (relays, buttons, RPM etc). To use them you need to set the output’s SERVOx_FUNCTION to -1. See GPIOs page for more information.
The numbering of the GPIOs for PIN variables in ArduPilot is:
FMU pins:
PWM1 50
PWM2 51
PWM3 52
PWM4 53
PWM5 54
PWM6 55
PWM7 56 (not 6C Mini)
PWM8 57 (not 6C Mini)
Analog inputs¶
The Pixhawk6C has an analog RSSI input pin:
Analog 3.3V RSSI input pin = 103
Connectors¶
Unless noted otherwise all connectors are JST GH
See Pixhawk6C pinout
Loading Firmware¶
The board comes pre-installed with an ArduPilot compatible bootloader, allowing the loading of xxxxxx.apj firmware files with any ArduPilot compatible ground station.
Firmware for these boards can be found here in sub-folders labeled “Pixhawk6C”.