Comment by hommelix

16 hours ago

> The updater device then sends 64 byte chunks spread over 9 CAN 0x384 frames

Classic CAN uses 8 bytes long frame, so 64 bits. Is it a typo in the post, vor is it using CAN-FD?

I read this as the chunks are 64 bytes and thus each chunk is split over 9 frames. I haven’t looked yet but it’s probably an ISO-TP esque framing protocol.

  • Yep, this is the case. Nine frames are transmitted with the first frame containing a sequence number and the first five bytes, followed by seven frames containing just data, and a final frame containing the last three bytes of data, and a two byte CRC.