External SPI bus

Connector pinout

Pin	Signal	Voltage
1	VCC	+5.0V
2	SPI CLK	+3.3V
3	SPI MISO	+3.3V
4	SPI MOSI	+3.3V
5	SPI CS	+3.3V
6	GPIO EXT	+3.3V
7	GND	GND

RDDRONE-FMUK66 Rev. C schematic

RDDRONE-FMUK66 Rev. B schematic

Rev. B (and older boards) are not supported anymore. This information is left for reference.