Remote Frame Reception - NEC V850ES/F 3-L Series User Manual

CAN Controller (CAN)

18.9.6 Remote frame reception

Caution
In all the operation modes, when a remote frame is received, the message
buffer that is to store the remote frame is searched from all the message
buffers satisfying the following conditions.
• Used as a message buffer
(MA0 bit of CnMCONFm register set to 1.)
• Set as a transmit message buffer
(MT[2:0] bits in CnMCONFm register set to 000
• Ready for reception
(RDY bit of CnMCTRLm register set to 1.)
• Set to transmit message
(RTR bit of CnMCONFm register is cleared to 0.)
• Transmission request is not set.
(TRQ bit of CnMCTRLm register is cleared to 0.)
Upon acceptance of a remote frame, the following actions are executed if the
ID of the received remote frame matches the ID of a message buffer that
satisfies the above conditions.
• The DLC[3:0] bit string in the CnMDLCm register store the received DLC
value.
• The CnMDATA0m to CnMDATA7m registers in the data area are not
updated (data before reception is saved).
• The DN bit of the CnMCTRLm register is set to 1.
• The CINTS1 bit of the CnINTS register is set to 1 (if the IE bit in the
CnMCTRLm register of the message buffer that receives and stores the
frame is set to 1).
• The receive completion interrupt (INTCnREC) is output (if the IE bit of the
message buffer that receives and stores the frame is set to 1 and if the CIE1
bit of the CnIE register is set to 1).
• The message buffer number is recorded in the receive history list.
When a message buffer is searched for receiving and storing a remote frame,
overwrite control by the OWS bit of the CnMCONFm register of the message
buffer and the DN bit of the CnMCTRLm register are not checked. The setting
of OWS is ignored, and DN is set in any case.
If more than one transmit message buffer has the same ID and the ID of the
received remote frame matches that ID, the remote frame is stored in the
transmit message buffer with the lowest message buffer number.
User's Manual U18743EE1V2UM00
Chapter 18
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