How to retain output state after firmware upgrade?

[jianfeng_guo]

Dear Support: 

We are working on a product based on imx.RT 1051, and need to retain the output state after firmware upgrade. Usually it need restart after frimware upgade, but the output will be reset during the restart.

Could you please kindly suggest us how to achieve the requirement: retain the output state after firmware upgrade.

Thank you.

[kerryzhou]

Hi @jianfeng_guo ，

    Thank you for your interest in the NXP MIMXRT product, I would like to provide service for you.

    What's the output state after firmware upgrade you want to retain?

    Do you mean the GPIO output state?

    In fact, the GPIO output state is controlled by the code, if you update the firmware, then reset, the code will be run, and the GPIO state is totally controlled by the code.

  But, I think you also can try the external pull resistor, whether it can retain the states or not? As, if the pin is input, so it is determined by your external signal.

Best Regards,

If you still have questions about it, please kindly let me know.

Best Regards,

Kerry

[jianfeng_guo]

thanks for your reply. The output is driven by GPIO, I'd like to retain the output as 1 during the reset. We found the GPIO is also reset to 0 when firmware reset. Please can you help to suggest how to retain the GPIO to 1 during reset? Thank you

[kerryzhou]

Hi @jianfeng_guo ,

   Which detail GPIO you are testing now?

   Tell me the pin, I need to check it, as some pin maybe controlled by the ROM during boot.

  Do you test any other GPIO pin, the same situation? When you test the GPIO, whether the GPIO voltage is power on or not?

Best Regards,

Kerry