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Chapter 19
CAN Controller (CAN)
Preliminary User’s Manual U17566EE1V2UM00
19.10.5
Remote frame reception
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
(CnMCONFm.MA0 bit set to 1.)
• Set as a transmit message buffer
(CnMCONFm.MT2 to CnMCONFm.MT0 bits set to 000B)
• Ready for reception
(CnMCTRLm.RDY bit set to 1.)
• Set to transmit message
(CnMCONFm.RTR bit is cleared to 0.)
• Transmission request is not set.
(CnMCTRLm.TRQ bit is set to 1.)
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 CnMDLCm.DLC3 to CnMDLCm.DLC0 bits store the received DLC
value.
• The CnMDATA0m to CnMDATA7m registers in the data area are not
updated (data before reception is saved).
• The CnMCTRLm.DN bit is set to 1.
• The CnINTS.CINTS1 bit is set to 1 (if the CnMCTRLm.IE bit of the message
buffer that receives and stores the frame is set to 1).
• The receive completion interrupt (INTCnRE) is output (if the IE bit of the
message buffer that receives and stores the frame is set to 1 and if the
CnIE.CIE1 bit is set to 1).
• The message buffer number is recorded in the receive history list.
Caution
When a message buffer is searched for receiving and storing a remote frame,
overwrite control by the CnMCONFm.OWS bit of the message buffer and the
DN bit are not affected.
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.
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