TMS570LS3137: Canbus transmit issue

Hi Ali,

Ali Ünsal said:

When I connect TMS570 only to the canbus analyzer, I see the messages coming out of TMS, but when I connect the device I will communicate with, only the messages coming from it come to the analyzer. TMS cannot send messages.

I don't understand your issue clearly. Can you please elaborate it further?

As far as i understand, 

You are doing two testings, 

1. You are connecting TMS570 with CAN analyzer and verifying the data between TMS570 and analyzer, in this case you are not facing any issues.

2. You are connecting TMS570 with other TMS570? There you can't see any data, right?

Is my understanding correct?

I am also suggesting you refer CAN video tutorial in below link once:

(+) [FAQ] TMS570LC4357: Examples and Demos available for Hercules Controllers (E.g. TMS570x, RM57x and RM46x etc) - Arm-based microcontrollers forum - Arm-based microcontrollers - TI E2E support forums

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Thanks & regards,
Jagadish.

Hi Jagadish, 

Answers to your questions:

1. Yes.

2. No, the other device is not TMS570, it is our customer's device. I don't know. When connected our TMS570 to other device, TMS570 cannot transmit CAN packages. The Tx buffer remains full.

Hi Ali,

Does the customer board have CAN transceiver on it?

Please refer my comment in below thread once:

(+) TMS570LC4357: Can communications between processors - Arm-based microcontrollers forum - Arm-based microcontrollers - TI E2E support forums

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Thanks & regards,
Jagadish.

Hi, 

I don't know customer's board specs. But I think there is because when I send CANBUS packet from Canbus Anaylzer it can receive those packages.

I debugged this situation, there is My observations:

* I see one time canGetLastError function returned 0x03 : canERROR_ACKNOWLEDGE (3): When a TX message wasn't acknowledged

* When Tx function is run; canTransmit return 0 with below block

/** - Check for pending message:
    *     - pending message, return 0
    *     - no pending message, start new transmission 
    */
    if ((node->TXRQx[regIndex] & bitIndex) != 0U)
    {
        success = 0U;
    }

I tried to clean the buffer but it failed.

Thanks & best regards

Hi Ali,

Ali Ünsal said:

But I think there is because when I send CANBUS packet from Canbus Anaylzer it can receive those packages.

If customer board working for CAN analyzer, then it should also work for TMS570. There might be just some configuration differences.

Can you please also verify which ID it is supporting 29-bit ID or 11-bit ID?

For example, if the customer board configured to support extended ID (29-bit) ID then make sure to enable the below check box in TMS570 side:

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Thanks & regards,
Jagadish.

Hi Jagadish,

jagadish gundavarapu said:

If customer board working for CAN analyzer, then it should also work for TMS570. There might be just some configuration differences.

You're right but there is no difference in the configurations. All of them are same ( bit rate, can version etc.) 

My observation is that when messages overlap, TMS570 cannot return to normal position for retransmission. I don't have any other ideas. 

Thanks & regards, 

Ali