SPI Communication Setup for L3GD20 Sensor on STM32F411VET Board

[swati]

Hi Everyone,

I am attempting to communicate with the L3GD20 sensor via SPI communication using the STM32F411VET Board.

Here is my code:

#include "main.h"

#include <stdio.h>

#include <string.h>

/* USER CODE BEGIN PD */

#define L3GD20_CS_PIN GPIO_PIN_3

#define L3GD20_CS_PORT GPIOE

#define L3GD20_WHO_AM_I 0x0F

#define L3GD20_I_AM 0xD4

SPI_HandleTypeDef hspi1;

UART_HandleTypeDef huart2;

static uint8_t TxData[2] = {0};

static uint8_t RxData[2] = {0};

void SystemClock_Config(void);

static void MX_GPIO_Init(void);

static void MX_SPI1_Init(void);

static void MX_USART2_UART_Init(void);

uint8_t L3GD20_Init(uint8_t regAddr);

int __io_putchar(int ch) {

// Transmit one character to the UART bit by bit

// Transmit one character to the UART

HAL_UART_Transmit(&huart2, (uint8_t *)&ch, 1, HAL_MAX_DELAY);

return ch;

}

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();

MX_USART2_UART_Init();

/* USER CODE BEGIN 2 */

/* USER CODE END 2 */

/* Infinite loop */

/* USER CODE BEGIN WHILE */

while (1)

{

/* USER CODE END WHILE */

/* USER CODE BEGIN 3 */

HAL_GPIO_TogglePin(GPIOD, GPIO_PIN_13);

HAL_Delay(500);

uint8_t whoAmIValue = L3GD20_Init(L3GD20_WHO_AM_I); // Assuming WHO_AM_I register is at address 0x0F

if (whoAmIValue == L3GD20_I_AM) // Replace with the correct expected value for L2GD20

{

printf("Sensor is connected");

}

else

{

// WHO_AM_I value does not match, there might be a communication issue

// Handle the error, log a message, or take appropriate action

printf("Sensor is not connected");

}

}

/* USER CODE END 3 */

}

/**

* @brief System Clock Configuration

* @retval None

*/

void SystemClock_Config(void)

{

RCC_OscInitTypeDef RCC_OscInitStruct = {0};

RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

/** Configure the main internal regulator output voltage

*/

__HAL_RCC_PWR_CLK_ENABLE();

__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);

/** 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_2;

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 */

}

/* USER CODE BEGIN 4 */

uint8_t L3GD20_Init(uint8_t regAddr) {

uint8_t readCommand = regAddr | 0x80;

uint8_t receivedData;

// Select the L3GD20 device (if using hardware NSS)

HAL_GPIO_WritePin(L3GD20_CS_PORT, L3GD20_CS_PIN, GPIO_PIN_RESET);

HAL_Delay(50);

// Send command to read WHO_AM_I register

if (HAL_SPI_Transmit(&hspi1, &readCommand, 1, HAL_MAX_DELAY) != HAL_OK) {

Error_Handler();

}

// Receive data from WHO_AM_I register

if (HAL_SPI_Receive(&hspi1, &receivedData, 1, HAL_MAX_DELAY) != HAL_OK) {

Error_Handler();

}

// Deselect the L3GD20 device (if using hardware NSS)

HAL_GPIO_WritePin(L3GD20_CS_PORT, L3GD20_CS_PIN, GPIO_PIN_SET);

// Print received data

printf("Received data from register 0x%02X: 0x%02X\n", regAddr, receivedData);

return receivedData;

}

I want to start with this sensor but i am receiving

Sensor is not connected Received data from register 0x0F: 0xD3
Sensor is not connected Received data from register 0x0F: 0xD3
Sensor is not connected Received data from register 0x0F: 0xD3
Sensor is not connected Received data from register 0x0F: 0xD3

Can anyone help me identify where I may be wrong?

[swati]

Hi,

Yes your suggestion helps me, as my sensor chip is different.