Hi Guofeng
If use 32bit xp,from first screenshot, your chip is secured.
On the debugger go to the menu TBDML HCS12->Unsecure...
This will run the "TBDML_Erase_unsecure_hcs12xx.cmd" file.
please check if your chip can be successfully unsecured.
if Unsecure can not fix the problem, try create a brand new project, test if the new project can be downloaded.
If still can't connect board, please test your board with another interface to verify if the chip itself has problem.
Have a great day,
Jennie Zhang
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