makeflyeasy PixSurveyA1¶

Specifications¶

Processor:
- 32-bit STM32F427VIT6 ARM Cortex M4 core with FPU
- 168 Mhz/256 KB RAM/2 MB Flash
- 32-bit failsafe co-processor (STMF103)
Sensors
- Three redundant IMUs (accels, gyros and compass)
- Gyro/Accelerometers: ICM20948 or MPU9250, ICM20602, MPU6000
- Barometers: Two redundant MS5611 barometers
- Compass: AK8960 or AK09916
Power
- Redundant power supply with automatic failover
- Power supply 4.8V-5.8V
Interfaces
- 14x PWM servo outputs (8 from IO, 6 from FMU)
- S.Bus servo output
- R/C inputs for CPPM, Spektrum / DSM and S.Bus
- 5x general purpose serial ports
- 2x I2C ports
- 2x CAN Bus interface
- MicroSD card reader
- Type-C USB
- High-powered piezo buzzer driver (on expansion board)
- Safety switch / LED
Dimensions
- Weight 117g
- Size 110mm x 100mm x 23mm

UART Mapping¶

SERIAL0 -> console (primary mavlink, usually USB)

SERIAL1 -> USART2 (telem1)

SERIAL2 -> USART3 (Telem2) RTS/CTS pins

SERIAL3 -> UART4 (primary GPS)

SERIAL4 -> UART8 (GPS2)

Connector pin assignments¶

TELEM1, TELEM2 ports¶

Pin	Signal	Volt
1	VCC	+5V
2	TX (OUT)	+3.3V
3	RX (IN)	+3.3V
4	GND	GND

I2C1, I2C2 port¶

PIN	SIGNAL	VOLT
1	VCC	+5V
2	SCL	+3.3V
3	SDA	+3.3V
4	GND	GND

CAN1, CAN2 port¶

PIN	SIGNAL	VOLT
1	VCC	+5V
2	CAN_H	+12V
3	CAN_L	+12V
4	GND	GND

Safety port¶

PIN	SIGNAL	VOLT
1	VCC	+5V
2	LED	+3.3V
3	SafKey	+3.3V

GPS1/I2C1, GPS2/I2C2 ports¶

PIN	SIGNAL	VOLT
1	VCC	+5V
2	TX	+3.3V
3	RX	+3.3V
4	SCL	+3.3V
5	SDA	+3.3V
6	GND	GND

Power1, Power2 ports¶

PIN	SIGNAL	VOLT
1	VCC	+5V
2	VCC	+5V
3	CURRENT	+3.3V
4	VOLTAGE	+3.3V
5	GND	GND
6	GND	GND

RC Input¶

The PPM/SBus.in 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 SERIAL4 (UART8) would need to be used for receiver connections. Below are setups using UART4. SERIAL4_PROTOCOL should be set to “23”.

FPort would require SERIAL4_OPTIONS be set to “15”.
CRSF would require SERIAL4_OPTIONS be set to “0”.
SRXL2 would require SERIAL4_OPTIONS be set to “4” and connects only the UART4 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 PixSurveyA1 supports up to 14 PWM outputs. All 14 outputs support all normal PWM output formats. All FMU outputs (9-14) support DShot.

The 6 FMU outputs are in 4 groups:

Outputs 9, 10, 11 and 12 in group1

Outputs 13 and 14 in group2

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.