Controller v2

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UART-based Controller

Command Format

Framing

The framing is self synchronizing. Each frame ends with an EOF marker. Everywhere else the EOF marker is escaped.

Frame Format

  • 1 byte sequence number
  • n byte frame data
  • 2 byte crc16 (CCITT) of frame data
  • 0x7e as EOF marker

Escaping

Escaping is done by byte stuffing. Escape character is 0x7d. Bytes to be escaped are 0x7d and 0x7e. The escape character is following by the byte to by escaped XOR 0x20.