TMS320F28062: can not download program with emulator the second time

Celes.

It sounds like you may have some board or ESD issues where you are damaging units during the programming process. I have a few thoughts.

• I hope that you are following safe production and handling procedures? https://www.esda.org/about-esd/esd-fundamentals/part-1-an-introduction-to-esd/
• Check your board voltages are there any that are not as expected?
• Does the programmed unit fail to operate after the first programming?
• Is the application code potentially damaging boards which in turn damages the MCU?
• Please look through the JTAG Connectivity Debug Guide for more instructions on how you may be able to isolate the problem.

Regards,

Mark

Mark, 

         Thanks for your prompt reply firstly, by the way I have further questions based on your answer and suggestion.

1. We following safe production handling procedure, after the first programming and testing and befor the second loading,  conformal coating had been used on the board for preventing ESD damaging.

2.This is our mature product, the voltage which can be tested are normal.

3. After the first programming before the second loading, the previous program can run normally,  we can test by testing facility watching its functional instruction on the led, motor, input output display etc.

This issue happen not on every board, just on a few about 20% this batch.  I hope you could give me more suggestion, thank you.

Celes,

I find the 20% reprogramming failure rate pretty disturbing. At this time I do not have many more thoughts as to why it is occurring.

Have you worked through the JTAG connectivity debug guide I previously linked to? It contains a decent workflow for attempting to recover failed units.

Have you checked the status of the XRSn pin on failing units? Were Boot mode pins changed and preventing the JTAG from connecting?

Can you try to do a A-B swap with a successfully reprogrammed unit and a failing one? move the MCU to a test socket, or to a board that was able to be reprogrammed. Also, place a unit that was successfully reprogrammed onto a board that was not working. This might tell us if the MCU itself has an issue or if there may be an issue with the failing PCB.

Regards,
Mark

Hi Celes,

Were you able to resolve your issue?

-Mark