kl36 continuous reset

[balaguruharihar]

Im using a custom board with kinetis kl36z256 mcu. The board was working fine. After a long continuous run the board stopped working. I couldn't reprogram the mcu anymore. Checked with the reset pin and found it was toggling continuously. Suspected a watchdog reset, hence erased the code an tried reprogramming. Still no success. At times the code gets written to the MCU but it gets locked with the reset handler. What may be the cause of it?

[jeremyzhou]

Hi Balaguru,

First of all, I'd like suggest that you should check the hardware circuit, likes the RESET_b and NMI_b should have 100nF capacitors close to the MCU for transient protection and an external 4.7K to 10K pullup is also recommended.

Then, you should hold the RESET_b pin to low voltage before programming by using the IDE with debug tool likes the J-link.

Next, you can release the RESET_b after click the debug button in the IDE.

Please have a try by following the steps above and inform me the updates.
Have a great day,
Ping

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