TMS570LS3137: Implement of CAN loopback test

Hello Arriy,

I need to look a little deeper into the reference code you linked to before I can answer your questions. I will look at these on Monday and get back to you.

Hello Arriy,

Arriy said:

1) This source code is implement to "24.14.4 Loop Back Combined with Silent Mode"  in Safety Manual(SPNU499B) ?

I don't believe that silent mode is being used in this example.

Arriy said:

(2) "IFX[2];" is what indicate?  I think, IFX[0] = buffer for RX,and IFX[1] = buffer for TX.

       After some data in IFX[0] , comparing whether the values IFX[1] and IFX[2] are the same or not ?

The test pass/fail is checked in this funcion:

unsigned int CAN_TestVerify()
{
 	 /* Read receive mailboxes */
    unsigned int error;
#ifdef	DEVICE_MODEL
	register DCAN_ST *ptr = (DCAN_ST *)DCAN1;
#else	
	register DCAN_ST *ptr = &e_DCAN1_ST;
#endif 
	error =0;

#if 0

   	ptr->IFX[0].IF1REQ_UN.IF1REQ_ST.MASK_B1		=1;
	ptr->IFX[0].IF1REQ_UN.IF1REQ_ST.ARB_B1		=1;
	ptr->IFX[0].IF1REQ_UN.IF1REQ_ST.CONTROL_B1	=1;
	ptr->IFX[0].IF1REQ_UN.IF1REQ_ST.CLRINTPEND_B1 =1;
	ptr->IFX[0].IF1REQ_UN.IF1REQ_ST.TXREQ_B1		=1;
	ptr->IFX[0].IF1REQ_UN.IF1REQ_ST.DATAA_B1		=1;
	ptr->IFX[0].IF1REQ_UN.IF1REQ_ST.DATAB_B1		=1;
	ptr->IFX[0].IF1REQ_UN.IF1REQ_ST.WR_B1 		=0; //Receive mailbox
	ptr->IFX[0].IF1REQ_UN.IF1REQ_ST.MSGNUM_B8 = 0x02; //2nd mailbox

#endif
	
	ptr->IFX[0].IF1REQ_UN.IF1REQ_UL = 0x007F0002;

	while(ptr->IFX[0].IF1REQ_UN.IF1REQ_ST.BUSY_B1 == 1);

	if(ptr->IFX[0].IFDATAA_UN.IFDATAA_UL!=DCAN_TxData[0]) error++;
	if(ptr->IFX[0].IFDATAB_UN.IFDATAB_UL!=DCAN_TxData[1]) error++;
    return (error);
}

The content of IFX0 is compared to the content of DCAN_TxData[0] and DCAN_TXData[1]. I don't see any references to IFX[2]?

However, there are 3 IFX registers. Usually IFX3 is used to access all CAN messages as itis the only one tied to the interrupt. For this test purpose it wasn't needed.

Also, you should be cautious about using some of the older examples. In this case the example does not originate from halcogen so using it in a project could be risky. For sure it would have to be verifiied by you/your company independently to assure it meets the device and application needs. I would highly recommend sticking with either safeTI diagnostic library code or Halcogen generated code only as these can be supported later by the CSPs that TI offeres or, at least you know that the code examples are developed in accordance with IEC61508.