24.3.2.10.1 Using Multiprocessor Communication Mode

The following procedure should be used to exchange data in Multiprocessor Communication mode (MPCM):

  1. All slave MCUs are in Multiprocessor Communication mode.
  2. The master MCU sends an address frame, and all slaves receive and read this frame.
  3. Each slave MCU determines if it has been selected.
  4. The addressed MCU will disable MPCM and receive all data frames. The other slave MCUs will ignore the data frames.
  5. When the addressed MCU has received the last data frame, it must enable MPCM again and wait for a new address frame from the master.

The process then repeats from step 2.

Using any of the 5- to 8-bit character frame formats is impractical, as the receiver must change between using n and n+1 character frame formats. This makes full-duplex operation difficult since the transmitter and receiver must use the same character size setting.