CAN can not accept the specified ID

[vnv]

Hi,

I am using the LPC11C24 CAN communication ,CAN can not accept the specified ID,My example comes from the official,Some of my examples are as follows：

msg_obj.msgobj = 1;
msg_obj.mode_id = 0x400 | CAN_MSGOBJ_EXT;  //CAN_MSGOBJ_EXT=0x20000000
msg_obj.mask = 0x1FFFFFFF;
LPC_CCAN_API->config_rxmsgobj(&msg_obj);
while (1) {
__WFI(); /* Go to Sleep */
}

CAN can accept 0x 80000400,0x 60000400,0x40000400,0x20000400 0x400 ID.I want to accept only the specified 0x400 Extended frame ID.what should I do？

[jeremyzhou]

Hi ，

You can use the following code instead of the original code to receive the frame whose identifier is 0x400.

     msg_obj.msgobj = 1;
     msg_obj.mode_id = 0x400;
     //msg_obj.mask = 0x700;
        msg_obj.mask = 0x7FF;
     LPC_CCAN_API->config_rxmsgobj(&msg_obj);‍‍‍‍‍‍‍‍‍‍

And the Figure 1 exemplifies the testing results.

Fig 1

Have a great day,
TIC

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[vnv]

Hi ,

You use the standard frame, I use the expansion of the frame.you can try my code.

msg_obj.msgobj = 1;
msg_obj.mode_id = 0x400 | CAN_MSGOBJ_EXT;
msg_obj.mask = 0x7FF;
LPC_CCAN_API->config_rxmsgobj(&msg_obj);

CAN can accept 0x 80000400,0x 60000400,0x40000400,0x20000400,0x400 ID.CAN can not accept the specified 0x400 Extended frame ID.

[jeremyzhou]

Hi ,

Thanks for your reply.

The extended ID can't beyond the 0x1FFF_FFFF, otherwise the ID can't be recognized.

     msg_obj.msgobj = 1;
     msg_obj.mode_id = 0x400|CAN_MSGOBJ_EXT;
     //msg_obj.mask = 0x700;
        msg_obj.mask = 0x1FFFFFFF;
        //msg_obj.mask = 0x7FF;
     LPC_CCAN_API->config_rxmsgobj(&msg_obj);‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

To implement receive the specific extend ID frame, please the following code.
Have a great day,
TIC

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Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------

[vnv]

Hi,

I understand, thank you very much for your answer