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基于STM32、HAL库的ADS1256IDBR模数转换器ADC驱动程序设计

news 来源：原创 2025/4/26 3:08:41

一、简介：

ADS1256IDBR是德州仪器(TI)生产的一款高精度、24位Δ-Σ模数转换器(ADC)，主要特性包括：

24位无丢失码分辨率
最高30kSPS的数据速率
低噪声：2.5μV RMS（在30SPS时）
8个单端或4个差分输入通道
内置可编程增益放大器(PGA)：1至64V/V
内置低漂移电压基准(2.5V)
SPI兼容接口
工作电压：3.3V或5V

二、硬件接口：

ADS1256引脚	STM32L4引脚	功能描述
DVDD	3.3V	数字电源
AVDD	3.3V	模拟电源
DGND	GND	数字地
AGND	GND	模拟地
CS	PA4	片选(低电平有效)
DIN	PA7	SPI数据输入(MOSI)
DOUT	PA6	SPI数据输出(MISO)
SCLK	PA5	SPI时钟
DRDY	PA3	数据就绪(低电平有效)
RESET	PA2	复位(低电平有效)

注意：模拟和数字地应在一点连接，电源引脚应加去耦电容(0.1μF)

三、头文件：

#ifndef ADS1256_H
#define ADS1256_H

#include "stm32l4xx_hal.h"

// ADS1256寄存器地址
#define ADS1256_REG_STATUS 0x00
#define ADS1256_REG_MUX 0x01
#define ADS1256_REG_ADCON 0x02
#define ADS1256_REG_DRATE 0x03
#define ADS1256_REG_IO 0x04
#define ADS1256_REG_OFC0 0x05
#define ADS1256_REG_OFC1 0x06
#define ADS1256_REG_OFC2 0x07
#define ADS1256_REG_FSC0 0x08
#define ADS1256_REG_FSC1 0x09
#define ADS1256_REG_FSC2 0x0A

// ADS1256命令
#define ADS1256_CMD_WAKEUP 0x00
#define ADS1256_CMD_RDATA 0x01
#define ADS1256_CMD_RDATAC 0x03
#define ADS1256_CMD_SDATAC 0x0F
#define ADS1256_CMD_RREG 0x10
#define ADS1256_CMD_WREG 0x50
#define ADS1256_CMD_SELFCAL 0xF0
#define ADS1256_CMD_SELFOCAL 0xF1
#define ADS1256_CMD_SELFGCAL 0xF2
#define ADS1256_CMD_SYSOCAL 0xF3
#define ADS1256_CMD_SYSGCAL 0xF4
#define ADS1256_CMD_SYNC 0xFC
#define ADS1256_CMD_STANDBY 0xFD
#define ADS1256_CMD_RESET 0xFE

// PGA增益设置
typedef enum {
ADS1256_GAIN_1 = 0,
ADS1256_GAIN_2,
ADS1256_GAIN_4,
ADS1256_GAIN_8,
ADS1256_GAIN_16,
ADS1256_GAIN_32,
ADS1256_GAIN_64
} ADS1256_Gain;

// 数据速率设置
typedef enum {
ADS1256_DRATE_30000 = 0xF0,
ADS1256_DRATE_15000 = 0xE0,
ADS1256_DRATE_7500 = 0xD0,
ADS1256_DRATE_3750 = 0xC0,
ADS1256_DRATE_2000 = 0xB0,
ADS1256_DRATE_1000 = 0xA1,
ADS1256_DRATE_500 = 0x92,
ADS1256_DRATE_100 = 0x82,
ADS1256_DRATE_60 = 0x72,
ADS1256_DRATE_50 = 0x63,
ADS1256_DRATE_30 = 0x53,
ADS1256_DRATE_25 = 0x43,
ADS1256_DRATE_15 = 0x33,
ADS1256_DRATE_10 = 0x23,
ADS1256_DRATE_5 = 0x13,
ADS1256_DRATE_2_5 = 0x03
} ADS1256_DataRate;

// 输入通道选择
typedef enum {
ADS1256_AIN0 = 0,
ADS1256_AIN1,
ADS1256_AIN2,
ADS1256_AIN3,
ADS1256_AIN4,
ADS1256_AIN5,
ADS1256_AIN6,
ADS1256_AIN7,
ADS1256_AINCOM
} ADS1256_Input;

typedef struct {
SPI_HandleTypeDef *hspi;
GPIO_TypeDef *cs_port;
uint16_t cs_pin;
GPIO_TypeDef *drdy_port;
uint16_t drdy_pin;
GPIO_TypeDef *reset_port;
uint16_t reset_pin;
ADS1256_Gain gain;
ADS1256_DataRate data_rate;
} ADS1256_HandleTypeDef;

// 函数声明
void ADS1256_Init(ADS1256_HandleTypeDef *hadc);
void ADS1256_Reset(ADS1256_HandleTypeDef *hadc);
void ADS1256_WriteReg(ADS1256_HandleTypeDef *hadc, uint8_t reg, uint8_t data);
uint8_t ADS1256_ReadReg(ADS1256_HandleTypeDef *hadc, uint8_t reg);
void ADS1256_SendCommand(ADS1256_HandleTypeDef *hadc, uint8_t cmd);
void ADS1256_WaitDRDY(ADS1256_HandleTypeDef *hadc);
void ADS1256_SetChannel(ADS1256_HandleTypeDef *hadc, ADS1256_Input positive, ADS1256_Input negative);
int32_t ADS1256_ReadData(ADS1256_HandleTypeDef *hadc);
float ADS1256_ReadVoltage(ADS1256_HandleTypeDef *hadc);

#endif // ADS1256_H

四、源文件：

#include "ads1256.h"
#include "stm32l4xx_hal.h"
#include <string.h>

// 私有函数声明
static void ADS1256_CS_Low(ADS1256_HandleTypeDef *hadc);
static void ADS1256_CS_High(ADS1256_HandleTypeDef *hadc);
static void ADS1256_Delay(uint32_t delay);

void ADS1256_Init(ADS1256_HandleTypeDef *hadc) {
// 硬件复位
ADS1256_Reset(hadc);

// 等待DRDY变低
ADS1256_WaitDRDY(hadc);

// 发送同步命令
ADS1256_SendCommand(hadc, ADS1256_CMD_SYNC);
ADS1256_Delay(10);
ADS1256_SendCommand(hadc, ADS1256_CMD_WAKEUP);
ADS1256_Delay(10);

// 配置寄存器
uint8_t buf[4];

// 配置MUX寄存器 (AIN0和AINCOM差分输入)
buf[0] = (ADS1256_AIN0 << 4) | ADS1256_AINCOM;
ADS1256_WriteReg(hadc, ADS1256_REG_MUX, buf[0]);

// 配置ADCON寄存器 (PGA使能，增益设置)
buf[1] = (0 << 3) | hadc->gain; // CLKOUT关闭，增益设置
ADS1256_WriteReg(hadc, ADS1256_REG_ADCON, buf[1]);

// 配置数据速率
ADS1256_WriteReg(hadc, ADS1256_REG_DRATE, hadc->data_rate);

// 自校准
ADS1256_SendCommand(hadc, ADS1256_CMD_SELFCAL);
ADS1256_Delay(100); // 等待校准完成
}

void ADS1256_Reset(ADS1256_HandleTypeDef *hadc) {
// 拉低复位引脚
HAL_GPIO_WritePin(hadc->reset_port, hadc->reset_pin, GPIO_PIN_RESET);
ADS1256_Delay(100);

// 释放复位引脚
HAL_GPIO_WritePin(hadc->reset_port, hadc->reset_pin, GPIO_PIN_SET);
ADS1256_Delay(1000); // 等待复位完成
}

void ADS1256_WriteReg(ADS1256_HandleTypeDef *hadc, uint8_t reg, uint8_t data) {
ADS1256_WaitDRDY(hadc);

ADS1256_CS_Low(hadc);

uint8_t txBuf[2];
txBuf[0] = ADS1256_CMD_WREG | reg;
txBuf[1] = 0x00; // 写入1个寄存器
txBuf[2] = data;

HAL_SPI_Transmit(hadc->hspi, txBuf, 3, HAL_MAX_DELAY);

ADS1256_CS_High(hadc);
}

uint8_t ADS1256_ReadReg(ADS1256_HandleTypeDef *hadc, uint8_t reg) {
ADS1256_WaitDRDY(hadc);

ADS1256_CS_Low(hadc);

uint8_t txBuf[3] = {0};
uint8_t rxBuf[3] = {0};

txBuf[0] = ADS1256_CMD_RREG | reg;
txBuf[1] = 0x00; // 读取1个寄存器

HAL_SPI_TransmitReceive(hadc->hspi, txBuf, rxBuf, 3, HAL_MAX_DELAY);

ADS1256_CS_High(hadc);

return rxBuf[2];
}

void ADS1256_SendCommand(ADS1256_HandleTypeDef *hadc, uint8_t cmd) {
ADS1256_WaitDRDY(hadc);

ADS1256_CS_Low(hadc);
HAL_SPI_Transmit(hadc->hspi, &cmd, 1, HAL_MAX_DELAY);
ADS1256_CS_High(hadc);
}

void ADS1256_WaitDRDY(ADS1256_HandleTypeDef *hadc) {
while (HAL_GPIO_ReadPin(hadc->drdy_port, hadc->drdy_pin) == GPIO_PIN_SET) {
// 等待DRDY变低
}
}

void ADS1256_SetChannel(ADS1256_HandleTypeDef *hadc, ADS1256_Input positive, ADS1256_Input negative) {
uint8_t mux = (positive << 4) | negative;
ADS1256_WriteReg(hadc, ADS1256_REG_MUX, mux);

// 发送同步和唤醒命令以应用新设置
ADS1256_SendCommand(hadc, ADS1256_CMD_SYNC);
ADS1256_Delay(10);
ADS1256_SendCommand(hadc, ADS1256_CMD_WAKEUP);
ADS1256_Delay(10);
}

int32_t ADS1256_ReadData(ADS1256_HandleTypeDef *hadc) {
ADS1256_WaitDRDY(hadc);

ADS1256_CS_Low(hadc);

uint8_t txBuf[4] = {ADS1256_CMD_RDATA, 0x00, 0x00, 0x00};
uint8_t rxBuf[4] = {0};

HAL_SPI_TransmitReceive(hadc->hspi, txBuf, rxBuf, 4, HAL_MAX_DELAY);

ADS1256_CS_High(hadc);

// 组合24位数据
int32_t value = (rxBuf[1] << 16) | (rxBuf[2] << 8) | rxBuf[3];

// 处理符号位扩展
if (value & 0x00800000) {
value |= 0xFF000000;
}

return value;
}

float ADS1256_ReadVoltage(ADS1256_HandleTypeDef *hadc) {
int32_t raw = ADS1256_ReadData(hadc);

// 计算电压 (假设使用内部2.5V基准)
float voltage = (raw * 2.5f) / (8388607.0f * (1 << hadc->gain));

return voltage;
}

static void ADS1256_CS_Low(ADS1256_HandleTypeDef *hadc) {
HAL_GPIO_WritePin(hadc->cs_port, hadc->cs_pin, GPIO_PIN_RESET);
}

static void ADS1256_CS_High(ADS1256_HandleTypeDef *hadc) {
HAL_GPIO_WritePin(hadc->cs_port, hadc->cs_pin, GPIO_PIN_SET);
}

static void ADS1256_Delay(uint32_t delay) {
HAL_Delay(delay);
}

五、应用：

#include "stm32l4xx_hal.h"
#include "ads1256.h"

SPI_HandleTypeDef hspi1;
ADS1256_HandleTypeDef hadc1;

void SystemClock_Config(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();

// 初始化ADS1256
hadc1.hspi = &hspi1;
hadc1.cs_port = GPIOA;
hadc1.cs_pin = GPIO_PIN_4;
hadc1.drdy_port = GPIOA;
hadc1.drdy_pin = GPIO_PIN_3;
hadc1.reset_port = GPIOA;
hadc1.reset_pin = GPIO_PIN_2;
hadc1.gain = ADS1256_GAIN_1;
hadc1.data_rate = ADS1256_DRATE_100;

ADS1256_Init(&hadc1);

while (1) {
// 读取AIN0电压
float voltage = ADS1256_ReadVoltage(&hadc1);

// 可以在此处添加电压处理逻辑
// 例如发送到串口或进行其他处理

HAL_Delay(100); // 每100ms读取一次
}
}

void SystemClock_Config(void) {
// 系统时钟配置代码 (根据具体硬件配置)
}

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_32;
hspi1.Init.FirstBit = SPI_FIRSTBIT_MSB;
hspi1.Init.TIMode = SPI_TIMODE_DISABLE;
hspi1.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
hspi1.Init.CRCPolynomial = 7;
if (HAL_SPI_Init(&hspi1) != HAL_OK) {
Error_Handler();
}
}

static void MX_GPIO_Init(void) {
GPIO_InitTypeDef GPIO_InitStruct = {0};

// 启用时钟
__HAL_RCC_GPIOA_CLK_ENABLE();

// DRDY引脚配置 (输入)
GPIO_InitStruct.Pin = GPIO_PIN_3;
GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
GPIO_InitStruct.Pull = GPIO_PULLUP;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

// CS引脚配置 (输出)
GPIO_InitStruct.Pin = GPIO_PIN_4;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_4, GPIO_PIN_SET); // 初始高电平

// RESET引脚配置 (输出)
GPIO_InitStruct.Pin = GPIO_PIN_2;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_2, GPIO_PIN_SET); // 初始高电平

// SPI引脚配置
GPIO_InitStruct.Pin = GPIO_PIN_5|GPIO_PIN_6|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(GPIOA, &GPIO_InitStruct);
}