Part Number:ADS1247
上边是原理图,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。VCC和VCC_A不是同一个电源供电,都是3.3V。START脚接高电平,CLK引脚接地。请用过的朋友帮助看一下,因为恒流源设置的是1毫安电流,参考电阻正常应该有1.6V左右的电压,但是一直测不到电压,是电路有问题导致的芯片没有工作吗,着实弄不懂了。
附上我的代码:
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_RDY6HAL_GPIO_ReadPin( GPIOC,temp_RDY6_Pin ) /******************ads1247寄存器地址*******************/#defineADS1247_CMD_WAKEUP0x00//退出睡眠模式 #defineADS1247_CMD_SLEEP0x02//进入睡眠模式 #defineADS1247_CMD_SYNC0x04//同步A/D转换 #defineADS1247_CMD_RESET0x06//上电复位值 #defineADS1247_CMD_NOP0xff//空操作 #defineADS1247_CMD_RDATA0x12//读一次数据 #defineADS1247_CMD_RDATAC0x14//连续读取数据 #defineADS1247_CMD_SDATAC0x16//停止连续读取数据 #defineADS1247_CMD_RREG0x20//读寄存器 #defineADS1247_CMD_WREG0x40//写寄存器 #defineADS1247_CMD_SYSOCAL0x60//系统偏移校准 #defineADS1247_CMD_SYSGCAL0x61//系统增益校准 #defineADS1247_CMD_SELFOCAL0x62//自偏置校准#defineADS1247_REG_MUX00x00//多路复用器控制寄存器0 #defineADS1247_REG_VBIAS0x01//偏置电压寄存器 #defineADS1247_REG_MUX10x02//多路复用器控制寄存器1 #defineADS1247_REG_SYS00x03//系统控制寄存器 #defineADS1247_REG_CFC00x04//漂移校准系数寄存器0 #defineADS1247_REG_CFC10x05//漂移校准系数寄存器1 #defineADS1247_REG_CFC20x06//漂移校准系数寄存器2 #defineADS1247_REG_FSC00x07//满量程标准系数寄存器0 #defineADS1247_REG_FSC10x08//满量程标准系数寄存器1 #defineADS1247_REG_FSC20x09//满量程标准系数寄存器2 #defineADS1247_REG_IDAC00x0a//IDAC控制寄存器0 #defineADS1247_REG_IDAC10x0b//IDAC控制寄存器1 #defineADS1247_REG_GPIOCFG0x0c//GPIO配置寄存器 #defineADS1247_REG_GPIODIR0x0d//GPIO方向寄存器 #defineADS1247_REG_GPIODAT0x0e//GPIO数据寄存器 /******************ads1247寄存器地址*******************/ //ADS1247支持的增益列表 #define ADC_GAIN_10x00 #define ADC_GAIN_20x10 #define ADC_GAIN_40x20 #define ADC_GAIN_80x30 #define ADC_GAIN_160x40 #define ADC_GAIN_320x50 #define ADC_GAIN_640x60 #define ADC_GAIN_1280x70 //ADS1248支持的转换速率列表 #define ADC_SPS_50x00 #define ADC_SPS_100x01 #define ADC_SPS_200x02 #define ADC_SPS_400x03 #define ADC_SPS_800x04 #define ADC_SPS_1600x05 #define ADC_SPS_3200x06 #define ADC_SPS_6400x07 #define ADC_SPS_10000x08 #define ADC_SPS_20000x09 //ADS124用于计算温度的参数 #define RREF820.0f//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 4,20SPSADS1247_WriteReg(ADS1247_REG_SYS0,&Cmd,1); //ADS1247_Calibrate(GainDataRate);Cmd=0x06; //xxxxx 110 设置IDAC1=IDAC2电流源为1mAADS1247_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-REFP0ADS1247_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; }
Amy Luo:
您好,
您是否将寄存器配置值读出来,以确认按期望值配置进去?
您是想采样datasheet典型应用中的比例测量吗?如果是这样的话,那么基准电压就需要使用外部基准REFP0/REFN0;
,
Zhang Xiaoxiang Zhang:
感谢您的回复,我确实是采用比例测量。根据您的建议,我读出来的寄存器值和写入的值一直对不上,也试了几个别人写的时序,看起来时序都没有问题,但是读出来的数都不对。因为读和写用的都是同一时序,可能是根本没写进去,请问有可能是什么原因,期待您的回复。
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Amy Luo:
您可以用示波器测量SPI(CS、SCLK、DIN、DOUT)读写寄存器通信波形吗?看下是否满足datasheet 寄存器读写时序,如下截图所示:
在ADS1247 产品首页 “设计与开发” –“软件开发”部分,提供了 ADS1x4x Firmware Example Code 希望对您有所帮助,或点击链接下载:https://www.ti.com.cn/cn/lit/zip/sbac144