Arduino for STM32

Posted: **Fri Mar 24, 2023 6:16 pm**

Hi everyone,

I am using STM32F103C8 blue pill board with arduino ide - stm32duino official core.

I am trying to configure the external interrupt on pin PB4, according to the datasheet.
However, seems like i have missed something or it doesn't work at all.

This is the piece of code I am using for testing purposes.

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void setup() {
  pinMode(PB4, INPUT_PULLDOWN);
  RCC->APB2ENR |= (1 << 0);
  AFIO->EXTICR[2] |= (1 << 0);
  EXTI->IMR |= (1 << 4);
  EXTI->RTSR |= (1 << 4);
  EXTI->FTSR &= ~(1 << 4);
  NVIC_SetPriority(EXTI4_IRQn, 0);
  NVIC_EnableIRQ(EXTI4_IRQn);
}

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void loop() {
  // put your main code here, to run repeatedly:
}

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void EXTI4_IRQHandler(void) {
  Serial.println("Trigger_Signal");
}

if i use

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attachInterrupt(PB4, EXTI4_IRQHandler, RISING);

, everything works but I can't get it to work through register manipulation.
Any Idea on how to do so?

Regards,

Posted: **Fri Mar 24, 2023 11:11 pm**

you need to unmask the line?

Posted: **Sat Mar 25, 2023 3:02 am**

dannyf wrote: ↑Fri Mar 24, 2023 11:11 pm you need to unmask the line?

This line:

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EXTI->IMR |= (1 << 4);

does the unmasking.

Posted: **Sat Mar 25, 2023 6:46 am**

EXTI4_IRQHandler is alread defined by the core interrupt part
https://github.com/stm32duino/Arduino_C ... t.cpp#L371

So if you want use it you have to disabled it by defining: HAL_EXTI_MODULE_DISABLED

https://github.com/stm32duino/Arduino_C ... figuration

You can use build_opt.h feature to do that:
https://github.com/stm32duino/Arduino_C ... uild_opt.h
with

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-DHAL_EXTI_MODULE_DISABLED

Finally, you have to declare the handler as extern "C":

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extern "C" void EXTI4_IRQHandler(void) {

Posted: **Sat Mar 25, 2023 9:35 am**

fpiSTM wrote: ↑Sat Mar 25, 2023 6:46 am EXTI4_IRQHandler is alread defined by the core interrupt part
https://github.com/stm32duino/Arduino_C ... t.cpp#L371

So if you want use it you have to disabled it by defining: HAL_EXTI_MODULE_DISABLED

https://github.com/stm32duino/Arduino_C ... figuration

You can use build_opt.h feature to do that:
https://github.com/stm32duino/Arduino_C ... uild_opt.h
with
Code: Select all
-DHAL_EXTI_MODULE_DISABLED
Finally, you have to declare the handler as extern "C":
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extern "C" void EXTI4_IRQHandler(void) {

Well, when i compile the sketch with extern "C", i get the following error:

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exit status 1

Compilation error: conflicting declaration of 'void EXTI4_IRQHandler()' with 'C' linkage

Posted: **Sat Mar 25, 2023 9:39 am**

Maybe a cache issue linked to arduino IDE. I got several with new version 2.x

Posted: **Sat Mar 25, 2023 10:10 am**

fpiSTM wrote: ↑Sat Mar 25, 2023 9:39 am Maybe a cache issue linked to arduino IDE. I got several with new version 2.x

So, how do we slove this issue?
What is the correct way of using external interrupt through register manipulation?
And how to use the build_opt.h file correctly?
Do I create header file called "build_opt" because arduino ide only accepts .h, .c, .cpp, .ino.
and then put this line in it

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-DHAL_EXTI_MODULE_DISABLED

and then drop that in the sketechbook folder directory which is located on C:\Users\"PC-USER"\Documents\Arduino

Am I configuring the registers correctly?

Posted: **Sat Mar 25, 2023 10:51 am**

Simply create build_opt.h file and add -D..... inside. About register Ididn't check.

Arduino for STM32

STM32f103xx External Interrupt using register - not working

STM32f103xx External Interrupt using register - not working

Re: STM32f103xx External Interrupt using register - not working

Re: STM32f103xx External Interrupt using register - not working

Re: STM32f103xx External Interrupt using register - not working

Re: STM32f103xx External Interrupt using register - not working

Re: STM32f103xx External Interrupt using register - not working

Re: STM32f103xx External Interrupt using register - not working

Re: STM32f103xx External Interrupt using register - not working