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stm32f103 startup io initialization problem

shan chen
Associate II


this is the first time I've had this problem , I describe this problem next:

1 the io initialization input is normal (this is the feature I want)

2 when I power off and restart, I find that the same pin initialization input is not responding

3 repeated power-off / power-on operation the pin initialization input sometimes does not respond

why does this happen, please tell me



Lead II

Not sure what you mean by "io initialization input is normal", but:

1. Check if BOOT0 pin is at logic LOW (connected to GND directly or via resistor).

2. If there is a high-capacity capacitor (like 1000uF) in the power supply path, wait longer between power off and power on, or use Reset button.

thank you for your help

1. "io initialization input is normal" means that the pin function i want is the input function.

2. just like you said, BOOT0 pin is at logic Low

3.max capacitor of the power supply is 100uf


Hi @shan chen ,

Please share your minimal project, not only the main file (if possible the .ioc file). So the members of the community and us can help you.

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.

thank you for your help 

sorry, i tried many times, the .ioc file transfer failed

do you have any suggestions about the problems I mentioned or have you encountered similar problems before

best wishes