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Chapter 34 CAN Controller
2.Register Description
■ Function of the IFx Command Mask Register (IFxCMSK)
The other bits of IFx Command Mask Register have different functions depending on the transfer direction :
• Direction = Write
[bit15-bit8] res Reserved Bits
[bit7] WR/RD Write / Read
0 Read: Transfer data from the Message Object addressed by the Command Request
Register into the selected Message Buffer Registers.
1 Write: Transfer data from the selected Message Buffer Registers to the Message
Object addressed by the Command Request Register.
[bit6] Mask Access Mask Bits
0 Mask bits unchanged.
1 Transfer Identifier Mask + MDir + MXtd to Message Object.
[bit5] Arb Access Arbitration Bits
0 Arbitration bits unchanged.
1 Transfer Identifier + Dir + Xtd + MsgVal to Message Object.
[bit4] Control Access Control Bits
0 Control Bits unchanged.
1 Transfer Control Bits to Message Object.
[bit3] CIP Clear Interrupt Pending Bit
When writing to a Message Object, this bit is ignored.
[bit2] TxReq/
NewDat
Access Transmission Request Bit
0 TxRqst bit unchanged
1 set TxRqst bit
[bit1] Data A Access Data Bytes 0-3
0 Data Bytes 0-3 unchanged.
1 Transfer Data Bytes 0-3 to Message Object.
[bit0] Data B Access Data Bytes 4-7
