Interfaces

Skynode S connectors

Connectors

Name	Connector	Description
USB-C	USB Type-C	General purpose USB 3.0 port
USB 2	JST GH 7-pin SM07B-GHS-TB	Host mode only USB 2 port
CSI 0 and 1	2x MIPI-CSI (4 lanes)	Standard MIPI camera interface, Raspberry Pi camera-compatible
ESC	JST SH 8-pin SM08B-SRSS-TB	Power supply and ESC control
GPS	JST GH 6-pin SM06B-GHS-TB	External GPS and Compass
EXTRAS 1	JST GH 10-pin SM10B-GHS-TB	FMU connections: CAN, UART, Analog, Timers
EXTRAS 2	JST GH 12-pin SM12B-GHS-TB	Linux GPIO/SPI and FMU auxillery PWM

USB C

The USB Type C connector is reversible and has two USB3.0 lanes and one USB2.0 routed. USB C supports speed up to 5Gbps in host or device mode. Connected to Linux only.

It is possible to use a passive break out board to route out up to 3 USB ports for simultaneous use: 2x USB3.0 and 1x USB2.0.

USB 2

The connector has 7 pins to avoid accidental connection with the GPS port. The extra power pins allow for more current to be supplied from 5V.

Pin	Name	Direction	Level	Function
1	5V_EXT	OUT	5V
2	5V_EXT	OUT	5V
3	D-	I/O	5V	USB2 host mode
4	D+	I/O	5V	USB2 host mode
5	GND
6	GND
7	GND

USB 2 supports speed up to 480Mbps in host mode only.

MIPI-CSI

22 pin 0.5mm ribbon cable, RPi camera compatible.

Pin	CSI0 Function	CSI1 Function
1	3.3V	3.3V
2	I2C4 SDA	I2C3 SDA
3	I2C4 SCL	I2C3 SCL
4	GND	GND
5	CSI0 LED	CSI1 LED
6	CSI Enable (shared with CSI1)	CSI Enable (shared with CSI0)
7	GND	GND
8	CSI0 D3 P	CSI1 D3 P
9	CSI0 D3 N	CSI1 D3 P
10	GND	GND
11	CSI0 D2 P	CSI1 D2 P
12	CSI0 D2 N	CSI1 D2 N
13	GND	GND
14	CSI0 CLK P	CSI1 CLK P
15	CSI0 CLK N	CSI1 CLK N
16	GND	GND
17	CSI0 D1 P	CSI1 D1 P
18	CSI0 D1 N	CSI1 D1 N
19	GND	GND
20	CSI0 D0 P	CSI1 D0 P
21	CSI0 D0 N	CSI1 D0 N
22	GND	GND

ESC

The TELEMETRY Pin (1) is currently not mapped in software.

The connector pinout is the same as the BLHeli_S ESC pinout. For other ESCs, you need an adapter cable!

Pin	Name	Direction	Level	Function
1	TELEMETRY	IN	3.3V	Digital telemetry input based on UART
2	CURRENT	IN	3.3V	Analog current measurement
3	PWM1	OUT	3.3V	Motor 1
4	PWM2	OUT	3.3V	Motor 2
5	PWM3	OUT	3.3V	Motor 3
6	PWM4	OUT	3.3V	Motor 4
7	VBAT	IN	≤36V	Battery input
8	GND

All PWM pins can be configured to output PWM, OneShot, or DShot protocol in PX4. The order can be freely defined in software.

The analog current measurement is limited to the 0-3.3V range, however, the pin will survive higher voltages up to 12V.

GPS

The connector pinout is the same as for most GPS receivers.

Pin	Name	Direction	Level	Function
1	5V_EXT	OUT	5V	5V power supply
2	UART8_TX	OUT	3.3V	GPS1 TX
3	UART8_RX	IN	3.3V	GPS1 RX
4	I2C1_SCL	I/O	3.3V	I2C for external compass
5	I2C1_SDA	I/O	3.3V	I2C for external compass
6	GND

Connected GPS and external compass are automatically recognized on boot.

I2C lines are pulled up with 2kΩ in Skynode. External pullups should not be added.

EXTRAS 1

All functions are connected to the FMU only and configured via PX4.

Pin	Name	Direction	Level	Function
1	5V_EXT	OUT	5V	5V power supply
2	3V3_EXT	OUT	3.3V	3.3V power supply
3	ADC1_INP	IN	3.3V	Analog input
4	SBUS_IN	IN	3.3V	SBUS protocol RC input
5	UART3_TX	OUT	3.3V	TELEM2 TX
6	UART3_RX	IN	3.3V	TELEM2 RX
7	PPM_IN	IN	3.3V	PPM input
8	CAN1 H	I/O	5V	CAN1 high
9	CAN1 L	I/O	5V	CAN1 low
10	GND

The CAN pins include an internal 120Ω bus termination.

EXTRAS 2

The PWM functions are connected to the FMU only and configured via PX4.

The GPIO and SPI signals are connected to the mission computer.

Pin	Name	Direction	Level	Function
1	5V_EXT	OUT	5V	5V power supply
2	GPIO0	I/O	3.3V	Controlled by Linux: Bank 0, Gpio 0
3	GPIO1	I/O	3.3V	Controlled by Linux: Bank 0, Gpio 1
4	SPI1_MISO	IN	3.3V	Controlled by Linux: SPI1 Input
5	SPI1_MOSI	OUT	3.3V	Controlled by Linux: SPI1 Output
6	SPI1_SCK	OUT	3.3V	Controlled by Linux: SPI1 Clock
7	SPI1_CS	I/O	3.3V	Controlled by Linux: Chip Select
8	PWM5	I/O	3.3V	Auxilary PWM1
9	PWM6	I/O	3.3V	Auxilary PWM2
10	PWM7	I/O	3.3V	Auxilary PWM3
11	PWM8	I/O	3.3V	Auxilary PWM4
12	GND	I/O

Please note that the pinout is different on v1.3 with two 5V pins without a GND pin!

Pin	Pinout v1.3	Pinout v1.4
1	5V_EXT	5V_EXT
2	5V_EXT extra pin	GPIO0
3	GPIO0	GPIO1
4	GPIO1	SPI1_MISO
5	SPI1_MISO	SPI1_MOSI
6	SPI1_MOSI	SPI1_SCK
7	SPI1_SCK	SPI1_CS
8	SPI1_CS	PWM5
9	PWM5	PWM6
10	PWM6	PWM7
11	PWM7	PWM8
12	PWM8	GND
	GND missing