My STM32F302C8T6 only runs the program when the code is loaded. If I reset it or power up, it does not run.

JMart.13 · ‎2022-01-02

Maybe is a hardware problem since the microcontroller is on a custom board I designed. The problem is the following:

The microcontroller only runs the program the moment I load the code, if I reset it or power up the board after a power-off it does not run the program.

This is the following circuit for the reset and BOOT0 pins:

I program the microcontroller with an external STLINK.

Thanks a lot for any help.

TDK · ‎2022-01-02

And does J1 have any jumper? BOOT0 must be grounded to run user code on reset. On some chips, the option bytes can override the BOOT0 pin.

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JMart.13 · ‎2022-01-03

Yes, BOOT0 has a jumper to ground.

TDK · ‎2022-01-03

Probably it is stuck ~~during startup~~ in your startup code then. Attach a debugger without resetting it to figure out where the CPU is. Could also be some other schematic error not shown in the snippet provided. LSE can take a while to come up and could be timing out. Same for HSE.

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JMart.13 · ‎2022-01-03

Hum ok ok, is strange because I generated the project using the STM32Cube IDE so I guess the startup code is ok, but I will have to check it.

JMart.13 · ‎2022-01-10

Hi @TDK I tried this week to solve the problem but it persists. this maybe can help. Whenever I enter the debug mode and press the reset button when it gets stuck, this message appears. What those it mean?

this is what is shown in the disassembly:

Thanks a lot.

Tesla DeLorean · ‎2022-01-10

Means its executing code in the System ROM

Look at the content of SCB->VTOR, and the Vector Table Entries. Both those visible at 0x00000000 and 0x08000000

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TDK · ‎2022-01-10

It sounds like you do not have BOOT0 held low and/or have disabled the BOOT0 pin functionality in option bytes.

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JMart.13 · ‎2022-01-10

Ok, when I reset the chip, the value of VTOR (TBLOFF) is 0 in all registers, and according to the ARM Cortex M4 manual, bit 29 determines if the Vector is in code or RAM, it means, that I should put it as 1? if yes, how to do it? hardcode it?

Thanks

JMart.13 · ‎2022-01-10

I am sure the BOOT0 is held low, but, there is a way to check it or check the BOOT0 functionality?