Pixhawk Adapter Board
Last updated
Last updated
The Pixhawk adapter board is used to break out the Skynode flight control interfaces on J3 and J4 to connectors and pinouts compatible to the Pixhawk-standard.
The voltage levels for all signals brought out from the FMU to the Pixhawk Adapter Board are either 5V or 3.3V compliant. Refer to the table below to check the voltage levels of specific pins. Exceeding these voltages will permanently damage the Flight Management Unit inside Skynode.
ID | Name | Connector | Description |
J11 | Primary | Molex Pico-Clasp 5015714007 | Connect to Skynode Primary (J4) |
J12 | Telem 1 | JST GH 6-pin SM06B-GHS-TB | |
J13 | GPS 1 | JST GH 10-pin SM10B-GHS-TB (until rev 5 included) JST GH 11-pin SM11B-GHS-TB (from rev 6 included) | Primary GPS with external compass, safety switch and led |
J14 | CAN 1 | JST GH 4-pin SM04B-GHS-TB | |
J15 | FMU | Pin Header TSW-108-08-G-T-RA | PWM channels from FMU, input capable |
J16 | SBUS RC | JST GH 3-pin SM03B-GHS-TB | SBUS protocol RC input |
J18 | I2C 1 | JST GH 4-pin SM04B-GHS-TB |
ID | Name | Connector | Description |
J21 | Secondary | Molex Pico-Claspre team is looki 5015714007 | Connect to Skynode Secondary (J3) |
J22 | SBUS OUT | JST GH 3-pin SM03B-GHS-TB | SBUS output |
J23 | GPS 2 | JST GH 6-pin SM06B-GHS-TB | Redundant GPS |
J24 | SPI | JST GH 11-pin SM11B-GHS-TB | |
J25 | IO | Pin Header TSW-108-08-G-T-RA | PWM channels from IO |
J26 | Telem 3 | JST GH 6-pin SM06B-GHS-TB | |
J27 | CAN 2 | JST GH 4-pin SM04B-GHS-TB | |
J28 | I2C 2 | JST GH 4-pin SM04B-GHS-TB |
Pin | Name | Dir | Lvl | Function |
1 | VDD_5V_HIPOWER | 5V | 5V supply for peripherals, max. 1.0A (fused) | |
2 | UART7_TX | OUT | 3.3V | Telem 1 TX |
3 | UART7_RX | IN | 3.3V | Telem 1 RX |
4 | UART7_CTS | IN | 3.3V | Telem 1 CTS |
5 | UART7_RTS | OUT | 3.3V | Telem 1 RTS |
6 | GND | Ground |
Pin | Name | Dir | Lvl | Function |
1 | VDD_5V_CAN1_GPS1 | 5V | 5V supply for primary GPS and CAN interface | |
2 | USART1_TX | OUT | 3.3V | GPS 1 TX |
3 | USART1_RX | IN | 3.3V | GPS 1 RX |
4 | I2C1_SCL | I/O | 3.3V | I2C SCL for external magnetometer |
5 | I2C1_SDA | I/O | 3.3V | I2C SDA for external magnetometer |
6 | GPS_PPS | IN | 3.3V | PPS signal from GPS module |
7 | FMU_IO_SAFETY_SWITCH_IN | IN | 3.3V | Safety switch state input |
8 | FMU_IO_nSAFETY_SWITCH_LED_OUT | OUT | 3.3V | Safety switch led output |
9 | FMU_VDD_3V3 | OUT | 3.3V | 3.3V supply for peripherals, max 50mA |
10 | BUZZER_1_INV | OUT | Buzzer output (open drain) | |
11 | GND | Ground |
I2C lines are pulled up with 1kΩ in Skynode. External pull up resistors shall not be added.
The highlighted pin 6 was added in rev 6 of the Pixhawk Adapter Board, to ensure compatibility with the PX4 F9P GPS module. For backwards compatibility with the Freefly RTK GPS module, a custom cable needs to be made.
Pin | Name | Dir | Lvl | Function |
1 | VDD_5V_CAN1_GPS1 | 5V | 5V supply for primary GPS and CAN interface | |
2 | CAN1_P | I/O | 5V | FMU CAN 1 |
3 | CAN1_N | I/O | 5V | FMU CAN 1 |
6 | GND | Ground |
Pin | Name | Dir | Lvl | PWM/ OneShot | DShot | Shared with PPB |
1 | FMU_CH1 | I/O | 3.3V | Yes | Yes | |
2 | FMU_CH2 | I/O | 3.3V | Yes | Yes | |
3 | FMU_CH3 | I/O | 3.3V | Yes | Yes | |
4 | FMU_CH4 | I/O | 3.3V | Yes | Yes | |
5 | FMU_CH5 | I/O | 3.3V | Yes | Yes | |
6 | FMU_CH6 | I/O | 3.3V | Yes | Yes | |
7 | FMU_CH7 | I/O | 3.3V | Yes | Yes | |
8 | FMU_CH8 | I/O | 3.3V | Yes | Yes |
Pin | Name | Dir | Lvl | Function |
1 | VDD_5V_SBUS_RC | 5V | 5V supply for RC receiver, max 250mA | |
2 | IO_SBUS_INPUT | IN | 3.3V | SBUS protocol RC input |
3 | GND | Ground |
Pin | Name | Dir | Lvl | Function |
1 | VDD_5V_CAN1_GPS1 | 5V | 5V supply for primary GPS and CAN interface | |
2 | I2C1_SCL | I/O | 3.3V | I2C SCL for external peripherals |
3 | I2C1_SDA | I/O | 3.3V | I2C SDA for external peripherals |
6 | GND | Ground |
I2C lines are pulled up with 1kΩ in Skynode. External pull up resistors shall not be added.
Pin | Name | Dir | Lvl | Function |
1 | VDD_5V_SBUS_RC | Not connected | ||
2 | IO_SBUS_OUTPUT | OUT | 3.3V | SBUS protocol output |
3 | GND | Ground |
Pin | Name | Dir | Lvl | Function |
1 | VDD_5V_PERIPH | 5V | 5V supply for peripherals | |
2 | USART8_TX | OUT | 3.3V | GPS 2 TX |
3 | USART8_RX | IN | 3.3V | GPS 2 RX |
4 | I2C2_SCL | I/O | 3.3V | I2C SCL for external magnetometer |
5 | I2C2_SDA | I/O | 3.3V | I2C SDA for external magnetometer |
6 | GND | Ground |
I2C lines are pulled up with 1kΩ in Skynode. External pull up resistors shall not be added.
Pin | Name | Dir | Lvl | Function |
1 | VDD_5V_PERIPH | |||
2 | SPI6_SCK | OUT | 3.3V | SPI Clock |
3 | SPI6_MISO | IN | 3.3V | SPI MISO |
4 | SPI6_MOSI | OUT | 3.3V | SPI MOSI |
5 | SPI6_nCS1 | OUT | 3.3V | Chip select 1 |
6 | NC | |||
7 | SPI6_nSYNC | OUT | 3.3V | Sync signal |
8 | SPI6_DRDY1 | IN | 3.3V | Data ready 1 |
9 | NC | |||
10 | SPI6_nRESET | OUT | 3.3V | Reset |
11 | GND |
Pin | Name | Dir | Lvl | PWM/ OneShot | DShot | Shared with PPB |
1 | IO_CH1 | OUT | 3.3V | Yes | ||
2 | IO_CH2 | OUT | 3.3V | Yes | ||
3 | IO_CH3 | OUT | 3.3V | Yes | ||
4 | IO_CH4 | OUT | 3.3V | Yes | ||
5 | IO_CH5 | OUT | 3.3V | Yes | ||
6 | IO_CH6 | OUT | 3.3V | Yes | ||
7 | IO_CH7 | OUT | 3.3V | Yes | ||
8 | IO_CH8 | OUT | 3.3V | Yes |
Pin | Name | Dir | Lvl | Function |
1 | VDD_5V_PERIPH | 5V | 5V supply for peripherals | |
2 | USART2_TX | OUT | 3.3V | Telem 3 TX |
3 | USART2_RX | IN | 3.3V | Telem 3 RX |
4 | NC | |||
5 | NC | |||
6 | GND | Ground |
Pin | Name | Dir | Lvl | Function |
1 | VDD_5V_PERIPH | 5V | 5V supply for peripherals | |
2 | CAN2_P | I/O | 5V | FMU CAN 2 |
3 | CAN2_N | I/O | 5V | FMU CAN 2 |
6 | GND | Ground |
Pin | Name | Dir | Lvl | Function |
1 | VDD_5V_PERIPH | 5V | 5V supply for peripherals | |
2 | I2C2_SCL | I/O | 3.3V | I2C SCL for external peripherals |
3 | I2C2_SDA | I/O | 3.3V | I2C SDA for external peripherals |
6 | GND | Ground |
I2C lines are pulled up with 1kΩ in Skynode. External pull up resistors shall not be added.
Take a look at the for details about the changes.
CAN bus termination on Skynode changed in RC11. Prior to , Skynode has a 120Ω bus termination resistor inside, with no CAN termination on the Pixhawk Adapter Boards (until rev 5 included). This configuration assumed that Skynode was at the end of the bus. Rev 11 and onwards has the 120Ω bus termination resistor on the Pixhawk Adapter Boards (from rev 6 included), without built-in termination inside of Skynode. When designing a wire harness instead of using the Pixhawk Adapter Boards, usage of 120Ω termination resistors at both ends of the bus is mandatory, following ISO 11898..
CAN bus termination on Skynode changed in RC11. Prior to , Skynode has a 120Ω bus termination resistor inside, with no CAN termination on the Pixhawk Adapter Boards (until rev 5 included). This configuration assumed that Skynode was at the end of the bus. Rev 11 and onwards has the 120Ω bus termination resistor on the Pixhawk Adapter Boards (from rev 6 included), without built-in termination inside of Skynode. When designing a wire harness instead of using the Pixhawk Adapter Boards, usage of 120Ω termination resistors at both ends of the bus is mandatory, following ISO 11898.
