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Omerbzkt
Visitor II
June 19, 2025
Question

SPI Communication error between STM32F407-DISCO and ADS199FE-PDK

  • June 19, 2025
  • 2 replies
  • 660 views

I am working on the communication between ADS199FE-PDK and the STM32F407-DISCO board. I created SPI code using the HAL library. MOSI line seems to be working, but MISO line returns 0xFF all the time. I cannot even read the registers. I am sharing my created code below. Also, I am sharing the logic analyser result of the SPI line. Thanks for your help.

Omerbzkt_0-1750333879626.png



/* USER CODE BEGIN Header */
/**
 ******************************************************************************
 * @file : main.c
 * @brief : Main program body
 ******************************************************************************
 * @attention
 *
 * Copyright (c) 2025 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 */
#define COMMAND_RESET	(0x06)
#define COMMAND_SDATAC	(0x11)
/* 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 */
void ADS1299_init(void);
uint8_t read_byte(uint8_t reg_addr);
void ADS1299_send_command(uint8_t command);
void write_byte(uint8_t reg_addr, uint8_t val_hex);
/* 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 */
 ADS1299_init();

 uint8_t RESET = 0x06;
 uint8_t SDATAC = 0x11;

 ADS1299_send_command(RESET);
 HAL_Delay(1000); // Wait for reset to complete
 ADS1299_send_command(SDATAC);
 HAL_Delay(1000);


 /* USER CODE END 2 */
 uint8_t id;
 /* Infinite loop */
 /* USER CODE BEGIN WHILE */
 while (1)
 {
 /* USER CODE END WHILE */
	write_byte(0x01, 0x96);
	id = read_byte(0x01);
	if(id == 0x96)
	{
		HAL_Delay(1000);
	}
	HAL_Delay(2000);

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

uint8_t read_byte(uint8_t reg_addr)
{
 uint8_t out = 0;
 uint8_t cmd[2] = {0x20 | reg_addr, 0x00}; // Read command + number of registers
 uint8_t dummy = 0x00;

 HAL_GPIO_WritePin(CS_Pin_GPIO_Port, CS_Pin_Pin, GPIO_PIN_RESET);
 HAL_SPI_Transmit(&hspi1, cmd, 2, 0x1000);
 HAL_SPI_TransmitReceive(&hspi1, &dummy, &out, 1, 0x1000);
 HAL_GPIO_WritePin(CS_Pin_GPIO_Port, CS_Pin_Pin, GPIO_PIN_SET);
 return out;
}

void write_byte(uint8_t reg_addr, uint8_t val_hex)
{
	uint8_t test = 0x00;

	HAL_GPIO_WritePin(CS_Pin_GPIO_Port, CS_Pin_Pin, GPIO_PIN_RESET);
	uint8_t adress = 0x40|reg_addr;
	HAL_SPI_Transmit(&hspi1, (uint8_t*)&adress, 1, 0x1000);
	HAL_SPI_Transmit(&hspi1, (uint8_t*)&test, 1, 0x1000);
	HAL_SPI_Transmit(&hspi1, (uint8_t*)&val_hex, 1, 0x1000);
	HAL_GPIO_WritePin(CS_Pin_GPIO_Port, CS_Pin_Pin, GPIO_PIN_SET);
}

void ADS1299_send_command(uint8_t command)
{
 HAL_GPIO_WritePin(CS_Pin_GPIO_Port, CS_Pin_Pin, GPIO_PIN_RESET);
 HAL_SPI_Transmit(&hspi1, &command, 1, 0x1000);
 HAL_GPIO_WritePin(CS_Pin_GPIO_Port, CS_Pin_Pin, GPIO_PIN_SET);
}

void ADS1299_power_up_seq(void)
{
 HAL_Delay(150); // Wait >128 ms for power stabilization
 HAL_GPIO_WritePin(Reset_pin_GPIO_Port, Reset_pin_Pin, GPIO_PIN_RESET);
 HAL_Delay(1); // 1 ms pulse
 HAL_GPIO_WritePin(Reset_pin_GPIO_Port, Reset_pin_Pin, GPIO_PIN_SET);
 HAL_Delay(10); // Wait after reset
}

void ADS1299_init(void)
{
	ADS1299_power_up_seq();
	HAL_Delay(1000);

}


/**
 * @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_ON;
 RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
 RCC_OscInitStruct.PLL.PLLM = 8;
 RCC_OscInitStruct.PLL.PLLN = 168;
 RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
 RCC_OscInitStruct.PLL.PLLQ = 7;
 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_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_5) != 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_2EDGE;
 hspi1.Init.NSS = SPI_NSS_SOFT;
 hspi1.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_64;
 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_GPIOE_CLK_ENABLE();
 __HAL_RCC_GPIOC_CLK_ENABLE();
 __HAL_RCC_GPIOH_CLK_ENABLE();
 __HAL_RCC_GPIOA_CLK_ENABLE();
 __HAL_RCC_GPIOB_CLK_ENABLE();
 __HAL_RCC_GPIOD_CLK_ENABLE();

 /*Configure GPIO pin Output Level */
 HAL_GPIO_WritePin(CS_I2C_SPI_GPIO_Port, CS_I2C_SPI_Pin, GPIO_PIN_RESET);

 /*Configure GPIO pin Output Level */
 HAL_GPIO_WritePin(OTG_FS_PowerSwitchOn_GPIO_Port, OTG_FS_PowerSwitchOn_Pin, GPIO_PIN_SET);

 /*Configure GPIO pin Output Level */
 HAL_GPIO_WritePin(GPIOD, LD4_Pin|LD3_Pin|LD5_Pin|LD6_Pin
 |Audio_RST_Pin, GPIO_PIN_RESET);

 /*Configure GPIO pin Output Level */
 HAL_GPIO_WritePin(CS_Pin_GPIO_Port, CS_Pin_Pin, GPIO_PIN_RESET);

 /*Configure GPIO pin Output Level */
 HAL_GPIO_WritePin(Reset_pin_GPIO_Port, Reset_pin_Pin, GPIO_PIN_RESET);

 /*Configure GPIO pin : CS_I2C_SPI_Pin */
 GPIO_InitStruct.Pin = CS_I2C_SPI_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
 HAL_GPIO_Init(CS_I2C_SPI_GPIO_Port, &GPIO_InitStruct);

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

 /*Configure GPIO pin : PDM_OUT_Pin */
 GPIO_InitStruct.Pin = PDM_OUT_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
 GPIO_InitStruct.Alternate = GPIO_AF5_SPI2;
 HAL_GPIO_Init(PDM_OUT_GPIO_Port, &GPIO_InitStruct);

 /*Configure GPIO pin : B1_Pin */
 GPIO_InitStruct.Pin = B1_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_IT_RISING;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 HAL_GPIO_Init(B1_GPIO_Port, &GPIO_InitStruct);

 /*Configure GPIO pin : I2S3_WS_Pin */
 GPIO_InitStruct.Pin = I2S3_WS_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
 GPIO_InitStruct.Alternate = GPIO_AF6_SPI3;
 HAL_GPIO_Init(I2S3_WS_GPIO_Port, &GPIO_InitStruct);

 /*Configure GPIO pins : BOOT1_Pin DRDY_pin_Pin */
 GPIO_InitStruct.Pin = BOOT1_Pin|DRDY_pin_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

 /*Configure GPIO pin : CLK_IN_Pin */
 GPIO_InitStruct.Pin = CLK_IN_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
 GPIO_InitStruct.Alternate = GPIO_AF5_SPI2;
 HAL_GPIO_Init(CLK_IN_GPIO_Port, &GPIO_InitStruct);

 /*Configure GPIO pins : LD4_Pin LD3_Pin LD5_Pin LD6_Pin
 Audio_RST_Pin */
 GPIO_InitStruct.Pin = LD4_Pin|LD3_Pin|LD5_Pin|LD6_Pin
 |Audio_RST_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
 HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);

 /*Configure GPIO pins : I2S3_MCK_Pin I2S3_SCK_Pin I2S3_SD_Pin */
 GPIO_InitStruct.Pin = I2S3_MCK_Pin|I2S3_SCK_Pin|I2S3_SD_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
 GPIO_InitStruct.Alternate = GPIO_AF6_SPI3;
 HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);

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

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

 /*Configure GPIO pins : OTG_FS_ID_Pin OTG_FS_DM_Pin OTG_FS_DP_Pin */
 GPIO_InitStruct.Pin = OTG_FS_ID_Pin|OTG_FS_DM_Pin|OTG_FS_DP_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
 GPIO_InitStruct.Alternate = GPIO_AF10_OTG_FS;
 HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

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

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

 /*Configure GPIO pins : Audio_SCL_Pin Audio_SDA_Pin */
 GPIO_InitStruct.Pin = Audio_SCL_Pin|Audio_SDA_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_AF_OD;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
 GPIO_InitStruct.Alternate = GPIO_AF4_I2C1;
 HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

 /*Configure GPIO pin : MEMS_INT2_Pin */
 GPIO_InitStruct.Pin = MEMS_INT2_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_EVT_RISING;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 HAL_GPIO_Init(MEMS_INT2_GPIO_Port, &GPIO_InitStruct);

 /* USER CODE BEGIN MX_GPIO_Init_2 */

 /* USER CODE END MX_GPIO_Init_2 */
}

/* USER CODE BEGIN 4 */

/* 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 */

 

    This topic has been closed for replies.

    2 replies

    T
    TDK
    Super User
    June 19, 2025

    How is it wired? Show pictures. MISO at 0xFF or 0x00 generally indicates wiring is not as expected, or pins are already in use, or some other setup issue.

    O
    OmerbzktAuthor
    Visitor II
    June 19, 2025

    bada3d6c-1680-403e-a84c-0c49022c46a5.jpg

    I am connecting pins using a breadboard. I tested the pins with a short circuit test all of them are connected. I am supplying AVDD and DVDD with 3V. Thanks for your reply @TDK 

    S
    Saket_Om
    Technical Moderator
    June 19, 2025

    Hello @Omerbzkt 

    Please use a short cable with wire wrapping to connect your device

    T
    TDK
    Super User
    June 19, 2025

    What pin is used for MISO? Is it in use by something else on the STM32F407G-DISC1 board? If you set that pin to output push/pull and disconnect from the ADS chip, can you toggle it and observe on the scope?

    If you connect MOSI to MISO, do you read back the same data you're sending out?

    O
    OmerbzktAuthor
    Visitor II
    June 19, 2025
    I am using PA6 as a MISO pin. The configuration for the MISO,MOSI and SCK
    is the default configs for the SPI. I tried readback operation and I can
    see same message that I sent. Did you see any misconfigutation in the code?
    T
    TDK
    Super User
    June 19, 2025

    No, I don't see any misconfiguration in what is presented. I suspect it's a hardware issue, not software. STM32 seems to be doing its job.

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