Transmit frame info (Tx Buffer )
| PRIO | If the TPM (Transmit Priority Mode) bit in the CANxMOD register is set to 1, enabled Tx Buffers contend for the right to send their messages based on this field. The buffer with the lowest TX Priority value wins the prioritization and is sent first. |
| RESERVED | Reserved. Read value is undefined, only zero should be written. |
| DLC | Data Length Code. This value is sent in the DLC field of the next transmit message. In addition, if RTR = 0, this value controls the number of Data bytes sent in the next transmit message, from the CANxTDA and CANxTDB registers: 0000-0111 = 0-7 bytes 1xxx = 8 bytes |
| RESERVED | Reserved. Read value is undefined, only zero should be written. |
| RTR | This value is sent in the RTR bit of the next transmit message. If this bit is 0, the number of data bytes called out by the DLC field are sent from the CANxTDA and CANxTDB registers. If this bit is 1, a Remote Frame is sent, containing a request for that number of bytes. |
| FF | If this bit is 0, the next transmit message will be sent with an 11-bit Identifier (standard frame format), while if it’s 1, the message will be sent with a 29-bit Identifier (extended frame format). |