Problem with SPI on bluepill module

[LLope.31]

SOLVED: was a problem with NSS pin, the code is GPIOA but NSS is GPIOB... thought I corrected it

Hello, I am trying to read register on a RFM69HW transceiver, it uses SPI.

I have used this module extensively. Works perfectly on arduinos, esp, and others. With STM32, something bizare happens. STM32 can only read the register correctly the first time on debug. After the next read_register(), it returns a random value. I have tested reading a few registers (knowing what they should return) and got the same results: can only read the correct value in it once.

This is not a problem with the hardware. It is a problem with the HAL function for SPI.

I would appreciate help on this issue, as it cost me already a lot of time unfortunately.

Here is my main.c (its simple, just configured SPI1 in .ioc, and written the read_register() and write_register() and added calls in main() to test the reading and writing)(also I don't think I need to show you the print screens, its just that register 0x10 being read returns the correct 0x24 value and next time the exact same register is read, it returns different):

/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file : main.c
* @brief : Main program body
******************************************************************************
* @attention
*
* Copyright (c) 2023 STMicroelectronics.
* All rights reserved.
*
* This software is licensed under terms that can be found in the LICENSE file
* in the root directory of this software component.
* If no LICENSE file comes with this software, it is provided AS-IS.
*
******************************************************************************
*/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#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 hspi1;

/* USER CODE BEGIN PV */

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_SPI1_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 */

/* MCU Configuration--------------------------------------------------------*/

/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();

/* USER CODE BEGIN Init */

/* USER CODE END Init */

/* Configure the system clock */
SystemClock_Config();

/* USER CODE BEGIN SysInit */

/* USER CODE END SysInit */

/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_SPI1_Init();
/* USER CODE BEGIN 2 */
uint8_t version = read_register(0x01);
version = read_register(0x10);
version = read_register(0x10);
version = read_register(0x10);
uint8_t mode = read_register(0x01);
write_register(0x01, 0x0C); //reg opmode
mode = read_register(0x01);
for (int i = 0; i < 40; i++) {
uint8_t data = read_register(0x10);
}
/* USER CODE END 2 */

/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */

/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}

/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

/** Initializes the RCC Oscillators according to the specified parameters
* in the RCC_OscInitTypeDef structure.
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}

/** Initializes the CPU, AHB and APB buses clocks
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
{
Error_Handler();
}
}

/**
* @brief SPI1 Initialization Function
* @PAram None
* @retval None
*/
static void MX_SPI1_Init(void)
{

/* USER CODE BEGIN SPI1_Init 0 */

/* USER CODE END SPI1_Init 0 */

/* USER CODE BEGIN SPI1_Init 1 */

/* USER CODE END SPI1_Init 1 */
/* SPI1 parameter configuration*/
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 = 10;
if (HAL_SPI_Init(&hspi1) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN SPI1_Init 2 */

/* USER CODE END SPI1_Init 2 */

}

/**
* @brief GPIO Initialization Function
* @PAram 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_GPIOA_CLK_ENABLE();
__HAL_RCC_GPIOB_CLK_ENABLE();

/*Configure GPIO pin Output Level */
HAL_GPIO_WritePin(NSS_GPIO_Port, NSS_Pin, GPIO_PIN_RESET);

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

/* USER CODE BEGIN MX_GPIO_Init_2 */
/* USER CODE END MX_GPIO_Init_2 */
}

/* USER CODE BEGIN 4 */
uint8_t read_register(uint8_t register_address) {
uint8_t addr = register_address & 0x7F;
uint8_t rx_data;

HAL_GPIO_WritePin(GPIOA, NSS_Pin, GPIO_PIN_RESET); // CS low

HAL_SPI_Transmit(&hspi1, &addr, 1, HAL_MAX_DELAY); // Send command
HAL_SPI_Receive(&hspi1, &rx_data, 1, HAL_MAX_DELAY); // Receive data

HAL_GPIO_WritePin(GPIOA, NSS_Pin, GPIO_PIN_SET); // CS high

return rx_data;
}

void write_register(uint8_t register_address, uint8_t data) {
uint8_t addr = 0x80 | register_address;

HAL_GPIO_WritePin(GPIOA, NSS_Pin, GPIO_PIN_RESET); // CS low

HAL_SPI_Transmit(&hspi1, &addr, 1, HAL_MAX_DELAY); // Send command
HAL_SPI_Transmit(&hspi1, &data, 1, HAL_MAX_DELAY); // Receive data

HAL_GPIO_WritePin(GPIOA, NSS_Pin, GPIO_PIN_SET); // CS high

}
/* USER CODE END 4 */

/**
* @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.
* @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 /* USE_FULL_ASSERT */

Thank you, ill wait for some help

[RhSilicon]

I don't know if it can help in your case, but I found these videos about advanced debugging:

STM32CubeIDE Advanced Debug Features
https://youtube.com/playlist?list=PLnMKNibPkDnEDEsV7IBXNvg7oNn3MfRd6

[Karl Yamashita]

You don't check the HAL status when reading/writing so how do you know if the data is good? 

See what HAL status is returned

typedef enum
{
  HAL_OK       = 0x00U,
  HAL_ERROR    = 0x01U,
  HAL_BUSY     = 0x02U,
  HAL_TIMEOUT  = 0x03U
} HAL_StatusTypeDef;