Generation of clock signal of 800 khz on port PC2 STM32f29 mcro

[SGasp.1]

Hi amazing community.. 

I am working with stm32f429 and hal.

I have to generate a clock signal of 800 khz and duty cycle of 50% in a specific pin PC2

I cannot change pin since the hw is blocked and fixed.. 

The only way is to create it by using a delay ? 

Is it correct in this way ? 

#include "stm32f4xx_hal.h"

GPIO_InitTypeDef GPIO_InitStruct;

void SystemClock_Config(void);
static void MX_GPIO_Init(void);
void delay_us(uint32_t us);

int main(void)
{
  HAL_Init();
  SystemClock_Config();
  MX_GPIO_Init();
  
  while (1)
  {
    // Toggle PC2
    HAL_GPIO_TogglePin(GPIOC, GPIO_PIN_2);
    
    // Delay to approximate the desired frequency
    delay_us(625);
  }
}

void SystemClock_Config(void)
{
  // Same as before, no changes required
}

static void MX_GPIO_Init(void)
{
  __HAL_RCC_GPIOC_CLK_ENABLE();
  
  GPIO_InitStruct.Pin = GPIO_PIN_2;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  
  HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);
}

void delay_us(uint32_t us)
{
  // The actual delay may need adjustment based on the MCU clock frequency and compiler optimizations
  uint32_t count = (us * (SystemCoreClock / 1000000)) / 3;
  
  while (count--)
  {
    __asm__("nop");
  }
}

any other ideas to try?+

Thanks

[waclawek.jan · Accepted solution]

You can try toggling the pin in timer interrupt, but don't use Cube/HAL for that, write it yourself.

Another option is timer-triggered-DMA transferring from memory to GPIOx_BSRR.

JW

[Tesla DeLorean]

TIM+DMA+GPIO  +1

[SGasp.1]

Hi waclawek.. can you try an example for this ? 

You can try toggling the pin in timer interrupt

Thanks