CCS/TMS320F280049C: CAN reading, DLC, arbid

Hi Lakshmi,

       Not sure that will work but you can try reading CAN_IF2ARB register for the arbid:

                     rx_id = HWREG(CANB_BASE + CAN_O_IF2ARB) & 0x1FFFFFF; // [28:0] 29 bits arb id

       For DLC, try reading CAN_IF2MCTL register:

                       dlc = HWREG(CANB_BASE + CAN_O_IF2MCTL) & 0xF; // [3:0] 4 bits DLC

Regards,

Joseph

Hello Joseph,

I tried 

rx_id = HWREG(CANB_BASE + CAN_O_IF2ARB) & 0x1FFFFFF; 

rx_id stays at 0, while data is updated. I am using std_id still i need to see some junk in rx_id.

Some doubts:

1. in the above equation i don't see any macro or variable corresponding to obj_id, because i am using no 17.
2. During debug mode, the Message RAM cannot be accessed via the IFx register sets says in sprui33c.pdf

Regards
LT

Hi Lakshmi,

Couple of questions:

        - Which IF register were you using reading out the CAN message, is it IF1 or IF2?

        - For the ID that you are interested to read out, is it the message object ID (1 to 32) or the arbitration ID (unique ID from transmitting node, 11-bit std or 29-bit extended)?

Thanks,

Joseph

Hi,

 - Which IF register were you using reading out the CAN message, is it IF1 or IF2?

I am using this function from diverlib

CAN_readMessage(CANB_BASE, 17, rxMsgData);

- For the ID that you are interested to read out, is it the message object ID (1 to 32) or the arbitration ID (unique ID from transmitting node, 11-bit std or 29-bit extended)?

• Yes i am using message obj id 17, 
• I am receivng all messages and 

CAN_setupMessageObject(CANB_BASE, 17, 0x00,
CAN_MSG_FRAME_STD, CAN_MSG_OBJ_TYPE_RX, 0,
CAN_MSG_OBJ_RX_INT_ENABLE | CAN_MSG_OBJ_USE_ID_FILTER, 8);

Regards,
LT