
23.1.21.7 RECREQ Bit
The RECREQ bit determines transmit/receive mode shown in
Table 23.4. When the RECREQ bit is set to 1
(receive operation requested), the message slot is set to receive the data frame or remote frame. If the REMOTE
bit is set to 1 (remote frame transmitted/received) and the RSPLOCK bit is set to 0 (automatic answering to the
remote frame enabled), the data frame is transmitted automatically after the remote frame is received,
regardless of the RECREQ bit setting to 0.
Set the RECREQ bit to 0 (receive operation not requested) to transmit the data frame or remote frame.
Do not set both bits TRMREQ and RECREQ in the same message slot to 1.
23.1.21.8 TRMREQ Bit
The TRMREQ bit determines transmit/receive mode shown in
Table 23.4. When the TRMREQ bit is set to 1
(transmit operation requested), the data frame or remote frame is transmitted. If the REMOTE bit is set to 0
(remote frame transmitted/received), the message slot automatically switches to a receive slot for the data frame
after the remote frame is transmitted, regardless of the TRMREQ bit setting to 1.
Set the TRMREQ bit to 0 (transmit operation not requested) to receive the data frame or remote frame.
Do not set both bits TRMREQ and RECREQ in the same message slot to 1.
NOTES:
1. When a transmit operation request occurs in multiple message slots, the data frame or remote frame in the
slot which has the smallest slot number is transmitted first.
2. In single-shot mode, if a transmit operation is aborted due to the arbitration lost or transmit error, the value
in the C2MCTLi (i = 0 to 31) register is cleared to 00h.