ESPHome connects makers to CAN FD equipment

ESPHome adds support for Microchip’s MCP2517FD, MCP2518FD and MCP251863 controllers, giving makers a hardware connection for CAN FD, the extended version of the CAN device bus. Connected over SPI, they handle messages of up to 64 data bytes instead of classic CAN’s eight.

The component turns November 4’s message-handling groundwork into a hardware connection. Joe tested all three controller variants at data rates up to 5 Mbit/s, and the MCP2518FD at 8 Mbit/s.

The MCP2517FD has a hardware timing limitation that can still lose received messages or interrupt transmission. The driver warns when the controller reports the error and attempts to restore its configured mode.