SPI to RS485

V4 is now released. Please visit the latest version, which includes matching motor tuning tools, more sample projects, and a more complete protocol framework.

Protocol Overview

Use Case

Wiring

TX Protocol (SPI->RS485)

RX Protocol (RS485->SPI)

RS485 motors (fixed 21-byte frames)

CS1 controls RS485-1/RS485-2; CS2 controls RS485-3/RS485-4

Transparent, fixed length 21 bytes. Last two bytes reserved: last is CRC, second last is valid length.

Transparent, fixed length 21 bytes. Last two bytes reserved: last is CRC, second last is valid length.

Notes

  • To avoid conflicts with CAN, headers 0x45 0x54 and 0x53 0x54 are reserved for CAN.

  • The first two bytes of RS485 frames must not use those values.

Example Code

Python example (Unitree GOM8010 motor): spi_unitree_GO_M8010_6_demo.py