Electronic – STM32 SPI, can’t get it working

nucleospistm32

SOLUTION: CubeMX set the MOSI pin to be on another bus/port on the nucleo board (not sure why). Setting MOSI to the required GPIO pin manually worked.

I'm trying to set up a basic SPI interface using the HAL provided by ST on the STM32F767ZI nucleo board. What I am currently trying to do is to write anything to the SPI bus and view it using an oscilloscope to confirm I have it working. The code I'm using is follows:

/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include <TFT.h>
#include "stm32f7xx_hal.h"

SPI_HandleTypeDef hspi1;

void SystemClock_Config(void);
void Error_Handler(void);
static void MX_GPIO_Init(void);
static void MX_SPI1_Init(void);


int main(void)
{

  HAL_Init();

  SystemClock_Config();


  MX_GPIO_Init();
  MX_SPI1_Init();

    uint8_t xy[4] = {0x23,0x45,0x7A,0xE6};

    begin();
    while (1)
    {
        HAL_SPI_Init(&hspi1);
        HAL_SPI_Transmit(&hspi1,(uint8_t*)xy,4,1000);
        while(HAL_SPI_GetState(&hspi1) != HAL_SPI_STATE_READY);
        HAL_SPI_DeInit(&hspi1);
    }
}

/** System Clock Configuration
*/
void SystemClock_Config(void)
{

  RCC_OscInitTypeDef RCC_OscInitStruct;
  RCC_ClkInitTypeDef RCC_ClkInitStruct;
  RCC_PeriphCLKInitTypeDef PeriphClkInitStruct;

    /**Configure the main internal regulator output voltage 
    */
  __HAL_RCC_PWR_CLK_ENABLE();

  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE3);

    /**Initializes the CPU, AHB and APB busses clocks 
    */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.HSICalibrationValue = 16;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
  RCC_OscInitStruct.PLL.PLLM = 8;
  RCC_OscInitStruct.PLL.PLLN = 108;
  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV6;
  RCC_OscInitStruct.PLL.PLLQ = 2;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

    /**Initializes the CPU, AHB and APB busses clocks 
    */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1) != HAL_OK)
  {
    Error_Handler();
  }

  PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_I2C2;
  PeriphClkInitStruct.I2c2ClockSelection = RCC_I2C2CLKSOURCE_PCLK1;
  if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

    /**Configure the Systick interrupt time 
    */
  HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq()/1000);

    /**Configure the Systick 
    */
  HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);

  /* SysTick_IRQn interrupt configuration */
  HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
}

/* SPI1 init function */
static void MX_SPI1_Init(void)
{
    hspi1.Instance = SPI1;
    hspi1.Init.Mode = SPI_MODE_MASTER;
    hspi1.Init.Direction = SPI_DIRECTION_2LINES;
    hspi1.Init.DataSize = SPI_DATASIZE_8BIT;
    hspi1.Init.CLKPolarity = SPI_POLARITY_LOW;
    hspi1.Init.CLKPhase = SPI_PHASE_1EDGE;
    hspi1.Init.NSS = SPI_NSS_SOFT;
    hspi1.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_256;
    hspi1.Init.FirstBit = SPI_FIRSTBIT_MSB;
    hspi1.Init.TIMode = SPI_TIMODE_DISABLE;
    hspi1.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
    hspi1.Init.CRCPolynomial = 7;
    hspi1.Init.CRCLength = SPI_CRC_LENGTH_DATASIZE;
    hspi1.Init.NSSPMode = SPI_NSS_SOFT;

    HAL_SPI_MspInit(&hspi1);

    if (HAL_SPI_Init(&hspi1) != HAL_OK)
    {
        Error_Handler();
    }
}

/** Configure pins as 
        * Analog 
        * Input 
        * Output
        * EVENT_OUT
        * EXTI
     PD8   ------> USART3_TX
     PD9   ------> USART3_RX
     PA8   ------> USB_OTG_FS_SOF
     PA9   ------> USB_OTG_FS_VBUS
     PA10   ------> USB_OTG_FS_ID
     PA11   ------> USB_OTG_FS_DM
     PA12   ------> USB_OTG_FS_DP
*/
static void MX_GPIO_Init(void)
{

  GPIO_InitTypeDef GPIO_InitStruct;

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOE_CLK_ENABLE();
  __HAL_RCC_GPIOC_CLK_ENABLE();
  __HAL_RCC_GPIOF_CLK_ENABLE();
  __HAL_RCC_GPIOH_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOB_CLK_ENABLE();
  __HAL_RCC_GPIOD_CLK_ENABLE();
  __HAL_RCC_GPIOG_CLK_ENABLE();

  /*Configure GPIO pin : User_Blue_Button_Pin */
  GPIO_InitStruct.Pin = User_Blue_Button_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(User_Blue_Button_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pin : PF12 */
  GPIO_InitStruct.Pin = GPIO_PIN_12;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(GPIOF, &GPIO_InitStruct);

  /*Configure GPIO pins : LD3_Pin LD2_Pin */
  GPIO_InitStruct.Pin = LD3_Pin|LD2_Pin;
  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);

  /*Configure GPIO pins : STLK_RX_Pin STLK_TX_Pin */
  GPIO_InitStruct.Pin = STLK_RX_Pin|STLK_TX_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF7_USART3;
  HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);

  /*Configure GPIO pin : USB_PowerSwitchOn_Pin */
  GPIO_InitStruct.Pin = USB_PowerSwitchOn_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(USB_PowerSwitchOn_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pin : USB_OverCurrent_Pin */
  GPIO_InitStruct.Pin = USB_OverCurrent_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(USB_OverCurrent_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pins : USB_SOF_Pin USB_ID_Pin USB_DM_Pin USB_DP_Pin */
  GPIO_InitStruct.Pin = USB_SOF_Pin|USB_ID_Pin|USB_DM_Pin|USB_DP_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF10_OTG_FS;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /*Configure GPIO pin : USB_VBUS_Pin */
  GPIO_InitStruct.Pin = USB_VBUS_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(USB_VBUS_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOF, GPIO_PIN_12, GPIO_PIN_RESET);

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOB, LD3_Pin|LD2_Pin, GPIO_PIN_RESET);

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(USB_PowerSwitchOn_GPIO_Port, USB_PowerSwitchOn_Pin, GPIO_PIN_RESET);

}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

/**
  * @brief  This function is executed in case of error occurrence.
  * @param  None
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler */
  /* User can add his own implementation to report the HAL error return state */
  while(1) 
  {
  }
  /* USER CODE END Error_Handler */ 
}

#ifdef USE_FULL_ASSERT

/**
   * @brief Reports the name of the source file and the source line number
   * where the assert_param error has occurred.
   * @param file: pointer to the source file name
   * @param line: assert_param error line source number
   * @retval None
   */
void assert_failed(uint8_t* file, uint32_t line)
{
  /* USER CODE BEGIN 6 */
  /* User can add his own implementation to report the file name and line number,
    ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
  /* USER CODE END 6 */

}

#endif

An oscilloscope capture of the infinite loop yields the following result where yellow is SCK and blue is MOSI for SPI1 (CN7 pins 10 and 14 for the nucleo-f767zi). The number of clock cycles is consistent with the 4 bytes being sent using the transmit function however there is no actual data on the MOSI pin.

enter image description here
Any ideas what could be missing here?

UPDATE:

The HAL_SPI_MspInit() function appears in stm32f7xx_hal_spi.c and stm32f7xx_hal_msp.c. The first one looks like this:

__weak void HAL_SPI_MspInit(SPI_HandleTypeDef *hspi)
{
  /* Prevent unused argument(s) compilation warning */
  UNUSED(hspi);

  /* NOTE : This function should not be modified, when the callback is needed,
            the HAL_SPI_MspInit should be implemented in the user file
   */
}

The last one looks like this:

void HAL_SPI_MspInit(SPI_HandleTypeDef* hspi)
{

  GPIO_InitTypeDef GPIO_InitStruct;
  if(hspi->Instance==SPI1)
  {
  /* USER CODE BEGIN SPI1_MspInit 0 */

  /* USER CODE END SPI1_MspInit 0 */
    /* Peripheral clock enable */
    __HAL_RCC_SPI1_CLK_ENABLE();

    /**SPI1 GPIO Configuration    
    PA5     ------> SPI1_SCK
    PA6     ------> SPI1_MISO
    PD7     ------> SPI1_MOSI 
    */
    GPIO_InitStruct.Pin = GPIO_PIN_5;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
    GPIO_InitStruct.Alternate = GPIO_AF5_SPI1;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

    GPIO_InitStruct.Pin = GPIO_PIN_6;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
    GPIO_InitStruct.Alternate = GPIO_AF5_SPI1;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

    GPIO_InitStruct.Pin = GPIO_PIN_7;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
    GPIO_InitStruct.Alternate = GPIO_AF5_SPI1;
    HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);

  /* USER CODE BEGIN SPI1_MspInit 1 */

  /* USER CODE END SPI1_MspInit 1 */
  }

}

I am fairly certain that the last one is being executed since a break point within the function triggers. I am not sure what the other two are intended for.

Best Answer

I can see one problem for sure which is HAL related. The HAL_SPI_Transmit is not a ready to use function. It is a blocking SPI send function only without the blocking part.

So I do not know if there anything else wrong, but you certainly should wait after the SPI transmit as follows:

HAL_SPI_Transmit(&hspi1, &xy, 1, 1);
while(HAL_SPI_GetState(&hspi1) != HAL_SPI_STATE_READY);

You should wait for the end of the transmission, before moving on.