2025-02-28 11:57 AM - edited 2025-03-02 1:57 PM
Hello,
I'm running into an issue interfacing the STM32H7R3V8H6 with a MAX31856 where whenever I try to use any sort of SPI functionality, it returns HAL_Error. This issue surprises me because the code that I am using is identical to the code I used on another H7 chip and that worked.
Things I have tried:
1. Lowering the SPI clock speed.
2. Ensuring that the SPI and CS pins were set up correctly (CS pin was set to digital output and the GPIO was configured for the application not the boot. Same for the SPI pins.)
3. Changing the SPI GPIO pin speed to very fast.
4. Probing the signals with an oscilloscope (I couldn't get very good results since I'm probing the pins on a custom board, but I was able to verify that SCK was working, but I couldn't determine if MISO or MOSI was functional)
5. Switching SPI from SPI1 to SPI3.
For reference I am using SPI1/3 on pins PB3, PB4, and PB5.
#include "main.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
/* USER CODE END Includes */
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
/* USER CODE END PTD */
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD */
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
/* USER CODE END PM */
/* Private variables ---------------------------------------------------------*/
SPI_HandleTypeDef hspi3;
/* USER CODE BEGIN PV */
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
static void MPU_Config(void);
static void MX_GPIO_Init(void);
static void MX_SPI3_Init(void);
/* USER CODE BEGIN PFP */
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
/* USER CODE END 0 */
/**
* @brief The application entry point.
* @retval int
*/
int main(void)
{
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
/* MPU Configuration--------------------------------------------------------*/
MPU_Config();
/* MCU Configuration--------------------------------------------------------*/
/* Update SystemCoreClock variable according to RCC registers values. */
SystemCoreClockUpdate();
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_SPI3_Init();
/* USER CODE BEGIN 2 */
uint8_t byteBuf;
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
HAL_GPIO_WritePin(GPIOM, GPIO_PIN_8, 0);
HAL_StatusTypeDef ret = HAL_SPI_Transmit(&hspi3, 0x01, 1, 100);
ret = HAL_SPI_Receive(&hspi3, &byteBuf, 1, 100);
//HAL_Delay(10);
HAL_GPIO_WritePin(GPIOM, GPIO_PIN_8, 1);
HAL_Delay(10);
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
/**
* @brief SPI3 Initialization Function
* None
* @retval None
*/
static void MX_SPI3_Init(void)
{
/* USER CODE BEGIN SPI3_Init 0 */
/* USER CODE END SPI3_Init 0 */
/* USER CODE BEGIN SPI3_Init 1 */
/* USER CODE END SPI3_Init 1 */
/* SPI3 parameter configuration*/
hspi3.Instance = SPI3;
hspi3.Init.Mode = SPI_MODE_MASTER;
hspi3.Init.Direction = SPI_DIRECTION_2LINES;
hspi3.Init.DataSize = SPI_DATASIZE_8BIT;
hspi3.Init.CLKPolarity = SPI_POLARITY_LOW;
hspi3.Init.CLKPhase = SPI_PHASE_1EDGE;
hspi3.Init.NSS = SPI_NSS_SOFT;
hspi3.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_32;
hspi3.Init.FirstBit = SPI_FIRSTBIT_MSB;
hspi3.Init.TIMode = SPI_TIMODE_DISABLE;
hspi3.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
hspi3.Init.CRCPolynomial = 0x7;
hspi3.Init.NSSPMode = SPI_NSS_PULSE_ENABLE;
hspi3.Init.NSSPolarity = SPI_NSS_POLARITY_LOW;
hspi3.Init.FifoThreshold = SPI_FIFO_THRESHOLD_01DATA;
hspi3.Init.MasterSSIdleness = SPI_MASTER_SS_IDLENESS_00CYCLE;
hspi3.Init.MasterInterDataIdleness = SPI_MASTER_INTERDATA_IDLENESS_00CYCLE;
hspi3.Init.MasterReceiverAutoSusp = SPI_MASTER_RX_AUTOSUSP_DISABLE;
hspi3.Init.MasterKeepIOState = SPI_MASTER_KEEP_IO_STATE_DISABLE;
hspi3.Init.IOSwap = SPI_IO_SWAP_DISABLE;
hspi3.Init.ReadyMasterManagement = SPI_RDY_MASTER_MANAGEMENT_INTERNALLY;
hspi3.Init.ReadyPolarity = SPI_RDY_POLARITY_HIGH;
if (HAL_SPI_Init(&hspi3) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN SPI3_Init 2 */
/* USER CODE END SPI3_Init 2 */
}
/**
* @brief GPIO Initialization Function
* None
* @retval None
*/
static void MX_GPIO_Init(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
/* USER CODE BEGIN MX_GPIO_Init_1 */
/* USER CODE END MX_GPIO_Init_1 */
/* GPIO Ports Clock Enable */
__HAL_RCC_GPIOB_CLK_ENABLE();
__HAL_RCC_GPIOM_CLK_ENABLE();
/*Configure GPIO pin Output Level */
HAL_GPIO_WritePin(GPIOM, GPIO_PIN_8, GPIO_PIN_SET);
/*Configure GPIO pin : PM8 */
GPIO_InitStruct.Pin = GPIO_PIN_8;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
HAL_GPIO_Init(GPIOM, &GPIO_InitStruct);
/* USER CODE BEGIN MX_GPIO_Init_2 */
/* USER CODE END MX_GPIO_Init_2 */
}
/* USER CODE BEGIN 4 */
/* USER CODE END 4 */
/* MPU Configuration */
static void MPU_Config(void)
{
MPU_Region_InitTypeDef MPU_InitStruct = {0};
/* Disables the MPU */
HAL_MPU_Disable();
/** Initializes and configures the Region and the memory to be protected
*/
MPU_InitStruct.Enable = MPU_REGION_ENABLE;
MPU_InitStruct.Number = MPU_REGION_NUMBER0;
MPU_InitStruct.BaseAddress = 0x0;
MPU_InitStruct.Size = MPU_REGION_SIZE_4GB;
MPU_InitStruct.SubRegionDisable = 0x87;
MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
MPU_InitStruct.AccessPermission = MPU_REGION_NO_ACCESS;
MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_DISABLE;
MPU_InitStruct.IsShareable = MPU_ACCESS_SHAREABLE;
MPU_InitStruct.IsCacheable = MPU_ACCESS_NOT_CACHEABLE;
MPU_InitStruct.IsBufferable = MPU_ACCESS_NOT_BUFFERABLE;
HAL_MPU_ConfigRegion(&MPU_InitStruct);
/* Enables the MPU */
HAL_MPU_Enable(MPU_PRIVILEGED_DEFAULT);
}
/**
* @brief This function is executed in case of error occurrence.
* @retval None
*/
void Error_Handler(void)
{
/* USER CODE BEGIN Error_Handler_Debug */
/* User can add his own implementation to report the HAL error return state */
__disable_irq();
while (1)
{
}
/* USER CODE END Error_Handler_Debug */
}
#ifdef USE_FULL_ASSERT
/**
* @brief Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* file: pointer to the source file name
* 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 /* USE_FULL_ASSERT */
EDIT: I probed again with an oscilloscope and I'm actually pretty sure that SCK isn't working either, so I was likely mistaken before.
2025-03-06 7:30 AM
I checked the output on a scope after changing the pin to a GPIO output, and running the code:
while (1)
{
HAL_GPIO_TogglePin(GPIOB, GPIO_PIN_3);
HAL_Delay(10);
}
And the results were as expected; a square wave that oscillated between high and low every 10ms.
2025-07-28 2:49 AM
Hi I am having the same issue!
Wanted to ask if you manage to identify that the shorted SCK is the issue?
2025-07-28 3:54 AM
Oop nvm I found the problem its because my baud rate is too high.... I just had to reduce the speed/ increase prescalar