How to work with GPIO

[Filipx.87]

Please advise where I'm doing wrong, I need to create variables with GPIO output with variable assignment and I don't know how to make it work correctly. 'my_gpio_port' reports as undeclared, but the declaration is without errors. Thanx

GPIO_TypeDef* my_gpio_port;
uint16_t  my_gpio_pin;

  if (Device_Config == Device_A)
	{
		my_gpio_port = GPIOA;
		my_gpio_pin = GPIO_PIN_7;
	}
  else
	{
		my_gpio_port = GPIOG;
		my_gpio_pin = GPIO_PIN_4;
	}

HAL_GPIO_Write(my_gpio_port, my_gpio_pin, 1);

[mƎALLEm]

,Hello,

First could you please provide the MCU part number? You created this thread on STM32 wireless.

Second, where did you define that typedef?:

GPIO_TypeDef

Third, did you enable the Port RCC clock? did you configure the GPIO pins?

Why are you using such code to access the pins:

  if (Device_Config == Device_A)
	{
		my_gpio_port = GPIOA;
		my_gpio_pin = GPIO_PIN_7;
	}
  else
	{
		my_gpio_port = GPIOG;
		my_gpio_pin = GPIO_PIN_4;
	}

Then you use the HAL API to access another pin!

Need to clarify what you need to do.

[Filipx.87]

First could you please provide the MCU part number?

STM32F429ZIT6

You created this thread on STM32 wireless.

I'm sorry, I know I made a mistake and I can't edit it anymore.

where did you define that typedef?

In the int main(void)

[mƎALLEm]

Why are you using that kind of access in the first part

  if (Device_Config == Device_A)
	{
		my_gpio_port = GPIOA;
		my_gpio_pin = GPIO_PIN_7;
	}
  else
	{
		my_gpio_port = GPIOG;
		my_gpio_pin = GPIO_PIN_4;
	}

then you are using HAL for this part to set the GPIO pin?

HAL_GPIO_Write(my_gpio_port, my_gpio_pin, 1);

[mƎALLEm]

Meanwhile to do a direct access to the register: 

You can access it over BRR and BSRR or ODR registers:

GPIOx->BSRR to set the pin and  GPIOx->BRR to reset the pin.

You need to look at HAL_GPIO_WritePin() implementation.

[Andrew Neil]

---

@Filipx.87 wrote:

Please advise where I'm doing wrong

---

Not enough context to be sure.

---

@Filipx.87 wrote:

'my_gpio_port' reports as undeclared

---

Please post a minimum but complete example which illustrates this.

Also post the complete build output. You haven't said what tools you're using but, for STM32CubeIDE, select-all & copy from the 'Console' window:

https://community.st.com/t5/community-guidelines/how-to-write-your-question-to-maximize-your-chances-to-find-a/tac-p/725146/highlight/true#M54

[Andrew Neil]

---

@mƎALLEm wrote:

Why are you using that kind of access in the first part

Seems to be just to support 2 different configurations; equivalent to

if (Device_Config == Device_A)
{
	HAL_GPIO_Write( GPIOA, GPIO_PIN_7 );
}
else
{
	HAL_GPIO_Write( GPIOG, GPIO_PIN_4 );
}

@Filipx.87  - do you really need to do this at run time, or could it be done with conditional compilation?