STM32 DeInit SPI then Init SPI again doesn't work

Question

on my STM32F103C8T6 I am using SPI for communication and at one moment I need to disable it, make pins GPIO and drive them LOW. After some time need to release them from GPIO and give them back SPI function and communicate some more.

The code is generated with the latest STM32Cube and all works but bringing SPI back.

Here is the C-Pseudo just for an explanation first, below it is functions used to do work.

main(){

  HAL_Init();  

  SystemClock_Config();

  MX_GPIO_Init();   

  MX_DMA_Init();  

  MX_ADC1_Init();  

  MX_SPI1_Init();


  while(1){

    SPI1_TURN_OFF();// It seems (maybe) to work because I can use pins as GPIO

    // use gpio pins for some work  

     SPI1_TURN_ON(); // Registers look ok but it doesn't work

     COMMUNICATE_OVER_SPI(); // Does't work

  }

}

These are two functions that should turn off SPI and bring it back on.

static void SPI1_TURN_OFF(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};



  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOB, PIN_X |PIN_Y, GPIO_PIN_RESET);

  HAL_SPI_DeInit(&hspi1);


  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOB, PIN_A|PIN_B|PIN_C, GPIO_PIN_RESET);

  GPIO_InitStruct.Pin = PIN_A|PIN_B|PIN_C;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);


}

static void SPI1_TURN_ON(void){
      HAL_GPIO_WritePin(GPIOB, PIN_X |PIN_Y, GPIO_PIN_SET);

      HAL_GPIO_DeInit(GPIOB, PIN_A|PIN_B|PIN_C);

      MX_SPI1_Init();
}

I am not using anything out of general order described by STM32 HAL documentation, what could go wrong with this?

*Remark: There isn't any other code which does something to this in effect, how it looks here follows the same logic in business logic.

Tnx for helping in advance!

Please add the MX_SPI1_Init and MX_GPIO_Init to your question. It seems to me that you are re-purposing GPIOs but not reinitializing it for SPI work. — Tarick Welling

user505160 user505160 · Accepted Answer · 2019-10-03T09:23:51

I have found cause of this, so:

all functions from STM32 HAL library work ok
problem was completely different and relates to collision of SWO with SPI CLK line. (proved that issue with adding more debug output code and removing debugger and just using UART to print it).

I have posted another post about this matter.

STM32F103 SWO and SPI CLK collision

All in all,

If you de-init SPI and again init in the same way STM32Cube has done it is going to work (at least in my case).

Tnx everyone.

STM32 DeInit SPI then Init SPI again doesn't work

1 Answers