32170 Datasheet, PDF (712/881 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 32-BIT CMOS MICROCOMPUTER

13
CAN MODULE
13.8 Receiving Remote Frames
13.8 Receiving Remote Frames
13.8.1 Remote Frame Receive Procedure
The following describes the procedure for receiving remote frames.
(1) Initializing the CAN Message Slot Control Register
Initialize the CAN Message Slot Control Register for the slot in which you want to receive by
writing H'00 to the register.
(2) Confirming that reception is idle
Read the CAN Message Slot Control Register after being initialized and check the TRSTAT
(Transmit/Receive Status) bit to see that reception has stopped and remains idle. If this bit = 1, it
means that the CAN module is accessing the message slot, so you need to wait until the bit is
cleared.
(3) Setting the receive ID
Set the ID you want to receive in the message slot.
(4) Setting the Extended ID Register
Set the corresponding bit of the Extended ID Register to 0 when you want to receive a standard
frame or 1 when you want to receive an extended frame.
(5) Setting the CAN Message Slot Control Register
(a) When automatic response (data frame transmission) for remote frame reception is desired
Write H'60 to the CAN Message Slot Control Register to set the RR (Receive Request) and
RM (Remote) bits to 1.
(b) When automatic response (data frame transmission) for remote frame reception is not
needed
Write H'70 to the CAN Message Slot Control Register to set the RR (Receive Request), RM
(Remote), and RL (Automatic Response Enable) bits to 1.
Note: In BasicCAN mode, slots 14 and 15, although capable of receiving remote frames,
cannot automatically respond to remote frame reception.
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32170/32174 Group User's Manual (Rev. 2.1)