EK-TM4C123GXL: When using EK-TM4C123GXL and rewriting the program of an external device, an error occurs as soon as the verification process is started

Hi Tom,

  I understand you are trying to use the EK-TM4C123GXL LaunchPad as a ICDI debug probe to debug another target device. There are a few experiments to try here. Can you answer me a few questions?

  - Were you successfully able to program the external device at least one time or a few times? Or it is failing the first time you try to program it? This is an important question to know.

 - If you use EK-TM4C123GXL to debug and program another device, will you see the verification error? There are two things I want to check here. One is make sure it is not some type of connection issue or a board level issue. Another is to make sure this is not an isolated target MCU issue. If you can successfully program another device then it proves that your LaunchPad, your target board and the wirings between them are ok. 

  - Can you do an unlock operation for the target MCU. Go to 'Other Utilities' tab in LM flash program and select 'Unlock'. Follow the instructions to unlock the target device. Can you successfully unlock the device? After you unlock, can you reprogram the failing device again? Will you get the verification error again?

- In the 'Program' tab, can you un-check the 'Verify after program'? It is not that we want to ignore the issue. I just want to see if other issues will come up without the verify step? Suppose it finishes the programming, will the target device run the program successfully?

 - Do you have another debug probe such as XDS100, XDS200, or Jlink that you can try to program your target device? I hope you can at least borrow one. I understand it is to save cost by using EK-TM4C1213GXL as a debug probe. it is not the ideal way for debugging with bunch of blue wires and unsure of proper connection contacts. Can you repeat the same issue with a commercial debug probe?

 - If you can repeatedly see the verification issue on only one MCU but not others then it is likely the MCU is damaged. 

I will answer your question.

 - Were you successfully able to program the external device at least one time or a few times? Or it is failing the first time you try to program it? This is an important question to know.

    ** I got an error when I tried to program for the first time. Also, if you try the program process again, the same error will occur.

 - If you use EK-TM4C123GXL to debug and program another device, will you see the verification error? There are two things I want to check here. One is make sure it is not some type of connection issue or a board level issue. Another is to make sure this is not an isolated target MCU issue. If you can successfully program another device then it proves that your LaunchPad, your target board and the wirings between them are ok. 

    ** I tried it on another same external device, but I got the same error, so I don't think it's a communication or board level issue.

  - Can you do an unlock operation for the target MCU. Go to 'Other Utilities' tab in LM flash program and select 'Unlock'. Follow the instructions to unlock the target device. Can you successfully unlock the device? After you unlock, can you reprogram the failing device again? Will you get the verification error again?

    ** I tried to unlock the target device. However, another error [** ERROR **: Unable to initialaize target --0!] occurred and the process of the program could not be executed.

- In the 'Program' tab, can you un-check the 'Verify after program'? It is not that we want to ignore the issue. I just want to see if other issues will come up without the verify step? Suppose it finishes the programming, will the target device run the program successfully?

    ** Even if I removed [Verify After Program], the process of the program did not complete normally and [Reset MCU After Program] was not executed.

 - Do you have another debug probe such as XDS100, XDS200, or Jlink that you can try to program your target device? I hope you can at least borrow one. I understand it is to save cost by using EK-TM4C1213GXL as a debug probe. it is not the ideal way for debugging with bunch of blue wires and unsure of proper connection contacts. Can you repeat the same issue with a commercial debug probe?

    ** I don't have another debug probe like XDS100, XDS200, or Jlink.

 - If you can repeatedly see the verification issue on only one MCU but not others then it is likely the MCU is damaged.

     ** We have verified with two MCUs, and both have the same result, so it is unlikely that the MCU has failed.

Best regards,

Shigeki Tanzawa

Hi Shigeki-san,

  Thanks for providing the answers. Based on your answers, I think it is very likely a board level issue, not the target MCU. Here is what I will suggest. 

  - Please tell me what is the target device you are trying to debug and program. Is it another TM4C12x device? If you try to debug a non-TM4C device, then it will not work. 

  - Can you carefully go through this app note in section 4.6 that illustrates how to use a EK-TM4C123GXL LaunchPad to debug out another device?   http://www.ti.com/lit/an/spma075/spma075.pdf

  - In the same app note, go to page 27 and follow the steps to troubleshoot JTAG issues.

  - Do you have another EK-TM4C123GXL LaunchPad? Can you repeat the same error? This step will really help if your first LaunchPad is working or not. 

  - I hope you have more than 2 target MCUs? Can you try a few more MCUs? Can you repeat the same error on all of them?

  - Please show the schematic of your target board? At the same time also please compare your schematic with section 4.1 on the app note. Section 4.1 on the app note has examples on how to design the JTAG connection.

  - Lastly, I really hope you have another commercial debug probe like XDS100 or XDS200.If you don't have one please borrow one. These are low cost debug probe that I think is worth the investment.  I tend to think it is a board level issue, not MCU. It is unheard of that multiple MCUs produce the same error. 

Hi Charies-san,

Thank you for your reply.

Will reply again.

  - Please tell me what is the target device you are trying to debug and program. Is it another TM4C12x device? If you try to debug a non-TM4C device, then it will not work. 

    ** The target device is not [TM4C12x device]. It's a third-party external device, so I don't know the internal details.

 - Can you carefully go through this app note in section 4.6 that illustrates how to use a EK-TM4C123GXL LaunchPad to debug out another device? 

    ** I checked the attached app note 4.6.

  - In the same app note, go to page 27 and follow the steps to troubleshoot JTAG issues.

    ** I don't have an XDS probe, so I can't run the content on this page.

  - Do you have another EK-TM4C123GXL LaunchPad? Can you repeat the same error? This step will really help if your first LaunchPad is working or not.

    ** I have only one [EK-TM4C123GXL LaunchPad].

  - I hope you have more than 2 target MCUs? Can you try a few more MCUs? Can you repeat the same error on all of them?

    ** There are only two target MCUs. Both get the same error. (** ERROR **: The verify failed! The First failing address: 0x00000XXX)

  - Please show the schematic of your target board? At the same time also please compare your schematic with section 4.1 on the app note. Section 4.1 on the app note has examples on how to design the JTAG connection.

    ** don't have a schematic of the target MCU. Because the target MCU is a third party, the schematic is not available.

 - Lastly, I really hope you have another commercial debug probe like XDS100 or XDS200.If you don't have one please borrow one. These are low cost debug probe that I think is worth the investment.  I tend to think it is a board level issue, not MCU. It is unheard of that multiple MCUs produce the same error. 

    ** I would consider purchasing a commercial debug probe such as the XDS100 or XDS200.

Best regards,

Shigeki Tanzawa