J-Tag debugging ML7218D1-MERCURY-M0-PE11 or TL7218D?

wes58

I am not sure whether this is the right forum section or whether I should post it in Hardware section, but I decided to post the question here. Is it possible to use J-Tag debugging on TL7218D/ML7218D1-MERCURY-M0-PE11 module? Reading the datasheet I can't see any pins defined for J-Tag connection on TL7218D.

TL_CHENDI

No worries, feel free to ask your questions.😄 Should your post be placed in an inappropriate forum section, we will advise you of the correct section for consultation. To get back to your question: The JTAG pins of the TL721x series chips are fixed as PC4~PC7. The TL7218D / ML7218D1 does not bring out these four IOs, so JTAG debugging is not supported for this chip/module. If JTAG functionality is required, you may contact our FAE to inquire about other packaged chips in the TL721x series. Thanks!

wes58

Thanks for your reply. So there is no debugging means for those modules. No J-Tag and not even pause/step/run in BDT through SWS! You just write the code and hope for the best. I wish I knew that before I spent $40 on 2 of these modules. It is also interesting that SEGGER shows TL7218D as supported by J-Link.  <div class="quote"><blockquote><font size="2"><a href="https://forum.telink-semi.cn/forum.php?mod=redirect&goto=findpost&pid=102927&ptid=98915" target="_blank"><font color="#999999">TL_CHENDI 发表于 2026-9-22 19:55</font></a></font><br /> No worries, feel free to ask your questions.😄 Should your post be placed in an inappropriate forum  ...</blockquote></div><br /> <br />

TL_CHENDI

Alright, let's clarify. Your original question was whether JTAG debugging is supported on the TL7218D / ML7218D1 module, and we have provided a clear answer: JTAG debugging is not supported. The information on SEGGER has not been updated in a timely manner. We apologize for the inconvenience caused, and we have contacted the relevant team to update it soon. Regarding SWS debugging support for the TL7218D / ML7218D1: if you review the ML7218D1 datasheet carefully, you will find that SWS debugging is supported, and the corresponding pin is PA7. We appreciate you selecting our modules for your development and debugging work. Should you have any further questions, please feel free to contact us. Thank you! <i class="pstatus"> 本帖最后由 TL_CHENDI 于 2026-9-23 14:45 编辑 </i><br /> <br />

wes58

I am sorry if my response upset you, but you would expect some debugging capabitlites from very NEW Telink product. You would understand my frustration if you spent over a week - luckily with Telink help - on Zigbee forum trying to find the reason for exception in the example code provided with Zigbee BLE concurrent SDK. When you read datasheet for ML7218D1-MERCURY-M0-PE11 you find this: > - secure debug port control What does it mean? And this: > - Supports SWS debug Interface > - SWS interface for  whole system Debugging is an important feature and it should be mentioned that there is none. You can use SWS for programming. As far as debugging support via SWS there is none. See response I got in TOOL section a while back: > Hi,for the first question,TL721X and other chips that use Risv-V MCU  which don't support debugging via single wire, so the BDT tool interface  grayscales the Run/Pause/Step functions, while the B85/B87 uses a TC  Core that supports these functions.

wes58

Although it doesn't matter now, I will add what information about debugging is in TL721x datasheet. Isn't it sufficient information for someone to decide to purchase this chip and expect that it would have JTAG and SDP debugging?  I wrote it so maybe Telink will update their documentation to make it clear. <i class="pstatus"> 本帖最后由 wes58 于 2026-9-24 07:56 编辑 </i><br /> <br />

TL_JIANBO

Hi Wes58, Thank you for pointing out this issue. We should clearly specify the supported debugging methods in the document “PS-ML7218D1-MERCURY-E\_Product\_Specification\_for\_Telink\_Module\_ML7218D1-MERCURY-M0-PE11.pdf” to avoid any misunderstandings caused by unclear descriptions. Currently, while investigating the program exception issue, please use the SWS interface for now. Thank you.