ADS1247: 芯片一直没有恒流源的输出，转换标志DRDY脚的电平变化正常，但是数据跳动幅度较大。

ads1247.h

#ifndef __ADS1247_H
#define __ADS1247_H
#ifdef __cplusplus
 extern "C" {
#endif

/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "gpio.h"  
  
/******************ads1247管脚与MCUSTM32F722对应关系**********
SCK(SPI2_SCK)-----------PB13
MISO(SPI2_MISO)---------PB14
MOSI(SPI2_MOSI)---------PB15  （SPI2）

NSS1(ADS_CS1)-----------PC0
NSS2(ADS_CS2)-----------PC2
NSS3(ADS_CS3)-----------PA4
NSS4(ADS_CS4)-----------PA6
NSS5(ADS_CS5)-----------PB0
NSS6(ADS_CS6)-----------PB12

DRDY1(PC1)---------PC1
DRDY2(PC3)---------PC3
DRDY3(PA5)---------PA5
DRDY4(PA7)---------PA7
DRDY5(PB1)---------PB1
DRDY6(PB2)---------PB2
******************ads1247管脚与MCU对应关系*******************/
//定义引脚有关宏函数
#define ADS_NSS1(n) (n?HAL_GPIO_WritePin(GPIOC,SPI2_NSS1_Pin,GPIO_PIN_SET):HAL_GPIO_WritePin(GPIOC,SPI2_NSS1_Pin,GPIO_PIN_RESET))
#define ADS_NSS2(n) (n?HAL_GPIO_WritePin(GPIOC,SPI2_NSS2_Pin,GPIO_PIN_SET):HAL_GPIO_WritePin(GPIOC,SPI2_NSS2_Pin,GPIO_PIN_RESET))
#define ADS_NSS3(n) (n?HAL_GPIO_WritePin(GPIOA,SPI2_NSS3_Pin,GPIO_PIN_SET):HAL_GPIO_WritePin(GPIOA,SPI2_NSS3_Pin,GPIO_PIN_RESET))
#define ADS_NSS4(n) (n?HAL_GPIO_WritePin(GPIOA,SPI2_NSS4_Pin,GPIO_PIN_SET):HAL_GPIO_WritePin(GPIOA,SPI2_NSS4_Pin,GPIO_PIN_RESET))
#define ADS_NSS5(n) (n?HAL_GPIO_WritePin(GPIOB,SPI2_NSS5_Pin,GPIO_PIN_SET):HAL_GPIO_WritePin(GPIOB,SPI2_NSS5_Pin,GPIO_PIN_RESET))
#define ADS_NSS6(n) (n?HAL_GPIO_WritePin(GPIOB,SPI2_NSS6_Pin,GPIO_PIN_SET):HAL_GPIO_WritePin(GPIOB,SPI2_NSS6_Pin,GPIO_PIN_RESET))

#define ADS_RDY6     HAL_GPIO_ReadPin( GPIOC,temp_RDY6_Pin )

/******************ads1247寄存器地址*******************/

 #define   ADS1247_CMD_WAKEUP     0x00//退出睡眠模式
 #define   ADS1247_CMD_SLEEP      0x02//进入睡眠模式
 #define   ADS1247_CMD_SYNC       0x04//同步A/D转换
 #define   ADS1247_CMD_RESET      0x06//上电复位值
 #define   ADS1247_CMD_NOP        0xff//空操作
 #define   ADS1247_CMD_RDATA      0x12//读一次数据
 #define   ADS1247_CMD_RDATAC     0x14//连续读取数据
 #define   ADS1247_CMD_SDATAC     0x16//停止连续读取数据
 #define   ADS1247_CMD_RREG       0x20//读寄存器
 #define   ADS1247_CMD_WREG       0x40//写寄存器
 #define   ADS1247_CMD_SYSOCAL    0x60//系统偏移校准
 #define   ADS1247_CMD_SYSGCAL    0x61//系统增益校准
 #define   ADS1247_CMD_SELFOCAL   0x62//自偏置校准
 
 #define   ADS1247_REG_MUX0       0x00//多路复用器控制寄存器0
 #define   ADS1247_REG_VBIAS      0x01//偏置电压寄存器
 #define   ADS1247_REG_MUX1       0x02//多路复用器控制寄存器1
 #define   ADS1247_REG_SYS0       0x03//系统控制寄存器
 #define   ADS1247_REG_CFC0       0x04//漂移校准系数寄存器0
 #define   ADS1247_REG_CFC1       0x05//漂移校准系数寄存器1
 #define   ADS1247_REG_CFC2       0x06//漂移校准系数寄存器2
 #define   ADS1247_REG_FSC0       0x07//满量程标准系数寄存器0
 #define   ADS1247_REG_FSC1       0x08//满量程标准系数寄存器1
 #define   ADS1247_REG_FSC2       0x09//满量程标准系数寄存器2
 #define   ADS1247_REG_IDAC0      0x0a//IDAC控制寄存器0
 #define   ADS1247_REG_IDAC1      0x0b//IDAC控制寄存器1
 #define   ADS1247_REG_GPIOCFG    0x0c//GPIO配置寄存器
 #define   ADS1247_REG_GPIODIR    0x0d//GPIO方向寄存器
 #define   ADS1247_REG_GPIODAT    0x0e//GPIO数据寄存器

/******************ads1247寄存器地址*******************/

//ADS1247支持的增益列表  
#define ADC_GAIN_1          0x00  
#define ADC_GAIN_2          0x10  
#define ADC_GAIN_4          0x20  
#define ADC_GAIN_8          0x30  
#define ADC_GAIN_16         0x40  
#define ADC_GAIN_32         0x50  
#define ADC_GAIN_64         0x60  
#define ADC_GAIN_128        0x70  

//ADS1248支持的转换速率列表  
#define ADC_SPS_5           0x00  
#define ADC_SPS_10          0x01  
#define ADC_SPS_20          0x02  
#define ADC_SPS_40          0x03  
#define ADC_SPS_80          0x04  
#define ADC_SPS_160         0x05  
#define ADC_SPS_320         0x06  
#define ADC_SPS_640         0x07  
#define ADC_SPS_1000        0x08  
#define ADC_SPS_2000        0x09

//ADS124用于计算温度的参数
#define RREF      820.0f   //参考电阻阻值REREF
#define RNOMINAL  100.0f   //阻值R0
#define RTD_A  3.9083e-3   //IEC751规定
#define RTD_B  -5.775e-7   //IEC751规定

//错误代码
#define ADS1247_OK            ((uint8_t)0x00)
#define ADS1247_ERROR         ((uint8_t)0x01)
#define ADS1247_BUSY          ((uint8_t)0x02)
#define ADS1247_TIMEOUT    ((uint8_t)0x03)

//函数定义，供主函数调用
void ADS1247_Init(void); 
 
void ADS1247_WriteReg(uint8_t RegAddr,uint8_t *Buffer,uint8_t Length); 
void ADS1247_ReadReg(uint8_t RegAddr,uint8_t *Buffer,uint8_t Length);

uint32_t ADS1247_ReadData_RTD(void);
float ADS1247_GetTempture(float *ReadTemp);

/* USER CODE END Prototypes */

#ifdef __cplusplus
}
#endif
#endif /*__ spi_H */

 

ads1247.c

#include "ADS1247.h"
#include "spi.h"
#include "math.h"
#include "stdio.h"

/*******************************************************************************  
* Function Name  : ADS1247_WriteCmd
* Description    : 向外设1247写命令
* Input          : Cmd 
* Output         :  
*******************************************************************************/ 
static void ADS1247_WriteCmd(uint8_t Cmd)             
 { 
 ADS_NSS6(0);
 HAL_SPI_Transmit(&hspi2,&Cmd,1,HAL_MAX_DELAY);
 ADS_NSS6(1);

 }
 
/*******************************************************************************  
* Function Name  : SPI_ADS1247_WriteReg
* Description    : 写ADS1247的寄存器
* Input          : 发送寄存器地址  发送数据字节
* Output         :  
*******************************************************************************/ 
 void ADS1247_WriteReg(uint8_t RegAddr,uint8_t *Buffer,uint8_t Length)  
{  
   uint8_t Cmd[2];  
   ADS_NSS6(0);
    Cmd[0]=ADS1247_CMD_WREG|(RegAddr&0x0f);  
    Cmd[1]=(Length-1)&0x0f; 
   HAL_SPI_Transmit(&hspi2, Cmd, 2,HAL_MAX_DELAY);  //指定向指定寄存器写入指定字节数据
   HAL_SPI_Transmit(&hspi2, Buffer, Length,HAL_MAX_DELAY);  //发送数据字节
   ADS_NSS6(1);
}

/*******************************************************************************  
* Function Name  : ADS1247_ReadReg 
* Description    : 读寄存器
* Input          : 发送寄存器地址  发送数据字节
* Output         :  
*******************************************************************************/
void ADS1247_ReadReg(uint8_t RegAddr,uint8_t *Buffer,uint8_t Length)
{
    uint8_t Cmd[2];
   ADS_NSS6(0);
    Cmd[0]=ADS1247_CMD_RREG|(RegAddr&0x0f);  
    Cmd[1]=(Length-1)&0x0f;   
  HAL_SPI_Transmit(&hspi2,Cmd, 2,HAL_MAX_DELAY);  //发送命令
   HAL_SPI_Receive(&hspi2, Buffer, Length, HAL_MAX_DELAY);//接收寄存器数据
   ADS_NSS6(1);
}

/*******************************************************************************  
* Function Name  : SPI_ADS1247_WaitBusy  
* Description    : 判断忙状态
* Input          :   
* Output         :  
*******************************************************************************/ 
void ADS1247_WaitBusy()  
{  
 uint8_t i=0;
 while(ADS_RDY6)
 {
    i++;
  HAL_Delay(5);
  if(i>200)
   break;
 }
} 
/*******************************************************************************  
* Function Name  : ADS1247_Calibrate  
* Description    : ADS1247校准
* Input          : None    
* Output         : None  
* Return         : None
*******************************************************************************/ 
//static uint8_t ADS1247_Calibrate(uint8_t Gain)  
//{  
//  uint8_t R=0;
//  uint8_t Cmd;  
//  ADS1247_WriteReg(ADS1247_REG_SYS0,&Gain,1); //设置增益和ADC输出速率    

//  Cmd=0x20;          //0 01 00 000 启动内部参考电压，选择REF0作为参考电压输入；  
//  ADS1247_WriteReg(ADS1247_REG_MUX1,&Cmd,1);       
// 
// ADS1247_WriteCmd(ADS1247_CMD_SELFOCAL);  //自偏校准
//  R |= ADS1247_WaitBusy();                 //等待完成      

// Cmd=0x21;  //0 01 00 001
// ADS1247_WriteReg(ADS1247_REG_MUX1,&Cmd,1); //设置系统监测外部参考电压偏移测量 
// 
// ADS1247_WriteCmd(ADS1247_CMD_SYSOCAL);   //系统偏移校准
//  R |= ADS1247_WaitBusy();                 //等待完成                 
//  
// Cmd=0x22;                                //设置系统监测外部参考电压偏移测量 
// ADS1247_WriteReg(ADS1247_REG_MUX1,&Cmd,1);      
// 
// ADS1247_WriteCmd(ADS1247_CMD_SYSOCAL);   //系统增益校准 
// R |= ADS1247_WaitBusy();                 //等待完成  

// return R;
//}
/*******************************************************************************  
* Function Name  : ADS1247_Init  
* Description    : ADS1247初始化
* Input          : None    
* Output         : None  
* Return         : None
*******************************************************************************/ 
void ADS1247_Init()
{  
   uint8_t Cmd; 
  ADS_NSS6(0);
    ADS1247_WriteCmd(ADS1247_CMD_RESET);
    HAL_Delay(20);

   Cmd=0x0A;  //00 001 010  不开启传感器检测；选定输入通道组合P-AIN1，N-AIN2；
  ADS1247_WriteReg(ADS1247_REG_MUX0,&Cmd,1);
   Cmd=0x00;  //0000 0110 不设置偏置电压
   ADS1247_WriteReg(ADS1247_REG_VBIAS,&Cmd,1);
   Cmd=0x20;  //0 01 10 000 启动内部参考电压，选择REFP0:REFN0两端电压作为ADC参考电平
  ADS1247_WriteReg(ADS1247_REG_MUX1,&Cmd,1);                        
  Cmd=0x22;  //0 010 0010 设置增益值、ADC输出数据率 4,20SPS                                             
  ADS1247_WriteReg(ADS1247_REG_SYS0,&Cmd,1); 
   
//   ADS1247_Calibrate(GainDataRate);  
  
  Cmd=0x06;  //xxxxx 110 设置IDAC1=IDAC2电流源为1mA   
  ADS1247_WriteReg(ADS1247_REG_IDAC0,&Cmd,1);
  Cmd=0x03;  //0000 0011 控制电流源输出引脚 IDAC1->AIN0  IDAC2->AIN3.                          
  ADS1247_WriteReg(ADS1247_REG_IDAC1,&Cmd,1); 
      
  Cmd=0x00;  //GPIO3-AIN3 GPIO2-AIN2  GPIO1-REFN0 GPIO0-REFP0
  ADS1247_WriteReg(ADS1247_REG_GPIOCFG,&Cmd,1); 
  Cmd=0x00;  //
  ADS1247_WriteReg(ADS1247_REG_GPIODIR,&Cmd,1);
  Cmd=0x00;  //
  ADS1247_WriteReg(ADS1247_REG_GPIODAT,&Cmd,1);
//    Delay_us(100);
  ADS_NSS6(1);

}

/*******************************************************************************  
* Function Name  : ADS1247_ReadData_RTD 
* Description    : 连续读ADS1247 转换值
* Input          : None  
* Output         : None  
* Return         : Register data
*******************************************************************************/  
uint32_t  ADS1247_ReadData_RTD(void)
{
 uint8_t  Cmd[4]={ADS1247_CMD_RDATA,ADS1247_CMD_NOP,ADS1247_CMD_NOP,ADS1247_CMD_NOP}; 
 uint8_t  Buf[4];
 uint32_t Data=0;
 
 ADS1247_WaitBusy();
 ADS_NSS6(0);
 HAL_SPI_TransmitReceive(&hspi2,Cmd,Buf,4,1000);
 ADS_NSS6(1);
 Data=Buf[1];
 Data=(Data<<8)|Buf[2];
 Data=(Data<<8)|Buf[3]; 
  return Data; 
}