使用

利用ADS8688采集互感器电压信号，使用软件SPI。

硬件电路

 模拟信号输入 

 ADS8688外围电路

 变量及宏定义

//位带操作#define BITBAND(addr, bitnum) ((addr & 0xF0000000)+0x2000000+((addr &0xFFFFF)<<5)+(bitnum<<2)) 
#define MEM_ADDR(addr)  *((volatile unsigned long  *)(addr)) 
#define BIT_ADDR(addr, bitnum)   MEM_ADDR(BITBAND(addr, bitnum)) //IO口地址映射#define GPIOA_ODR_Addr    (GPIOA_BASE+12) 	//0x4001080C 
#define GPIOB_ODR_Addr    (GPIOB_BASE+12)	//0x40010C0C 
#define GPIOC_ODR_Addr    (GPIOC_BASE+12) 	//0x4001100C 
#define GPIOD_ODR_Addr    (GPIOD_BASE+12) 	//0x4001140C   #define GPIOA_IDR_Addr    (GPIOA_BASE+8) 	//0x40010808 
#define GPIOB_IDR_Addr    (GPIOB_BASE+8) 	//0x40010C08 
#define GPIOC_IDR_Addr    (GPIOC_BASE+8) 	//0x40011008 
#define GPIOD_IDR_Addr    (GPIOD_BASE+8) 	//0x40011408  //IO口操作,只对单一的IO口,确保n的值小于16#define PAout(n)   BIT_ADDR(GPIOA_ODR_Addr,n)	//输出 
#define PAin(n)    BIT_ADDR(GPIOA_IDR_Addr,n)  	//输入 #define PBout(n)   BIT_ADDR(GPIOB_ODR_Addr,n)  	//输出 
#define PBin(n)    BIT_ADDR(GPIOB_IDR_Addr,n)  	//输入 #define PCout(n)   BIT_ADDR(GPIOC_ODR_Addr,n)  	//输出 
#define PCin(n)    BIT_ADDR(GPIOC_IDR_Addr,n)  	//输入 #define PDout(n)   BIT_ADDR(GPIOD_ODR_Addr,n)  	//输出 
#define PDin(n)    BIT_ADDR(GPIOD_IDR_Addr,n)  	//输入 /**************************************引脚定义*************************************************/#define ADS8688_CS 			PAout(4)
#define ADS8688_SCK 		PAout(5)
#define ADS8688_RST 		PBout(0)
#define ADS8688_MOSI 		PAout(7)#define ADS8688_MISO1		PAin(6)
#define ADS8688_MISO2 		PCin(4)
#define ADS8688_MISO3 		PCin(5)	/**************************************ADS8688寄存器********************************************///与命令寄存器相关的命令#define NO_OP		0x0000 
#define STDBY		0x8200 
#define PWR_DN  	0x8300 
#define RST			0x8500 
#define AUTO_RST	0xA000 
#define MAN_Ch_0	0xC000 
#define MAN_CH_1	0xC400 
#define MAN_Ch_2	0xC800 
#define MAN_Ch_3	0xCC00 
#define MAN_Ch_4	0xD000 
#define MAN_Ch_5	0xD400 
#define MAN_Ch_6	0xD800 
#define MAN_Ch_7	0xDC00 
#define MAN_AUX		0xE000//与程序寄存器相关的命令#define WRITE		1
#define READ 		0#define AUTO_SEQ_EN				0x01
#define Channel_Power_Down		0x02 
#define Feature_Select			0x03#define CH7_EN  0x80
#define CH6_EN  0x40
#define CH5_EN  0x20
#define CH4_EN  0x10
#define CH3_EN  0x08
#define CH2_EN  0x04
#define CH1_EN  0x02
#define CH0_EN  0x01 #define CH7_PD  0x80
#define CH6_PD  0x40
#define CH5_PD  0x20
#define CH4_PD  0x10
#define CH3_PD  0x08
#define CH2_PD  0x04
#define CH1_PD  0x02
#define CH0_PD  0x01#define Channel_0_Input_Range		0x05  
#define Channel_1_Input_Range		0x06 
#define Channel_2_Input_Range		0x07 
#define Channel_3_Input_Range		0x08 
#define Channel_4_Input_Range		0x09 
#define Channel_5_Input_Range		0x0A 
#define Channel_6_Input_Range		0x0B 
#define Channel_7_Input_Range		0x0C #define VREF_B_25				    0x00			//通道输入范围：±2.5×VREF
#define VREF_B_125				    0x01			//通道输入范围：±1.25×VREF
#define VREF_B_0625  			    0x02			//通道输入范围：±0.625×VREF
#define VREF_U_0_25				    0x05			//通道输入范围：0-2.5×VREF
#define VREF_U_0_125			    0x06			//通道输入范围：0-1.25×VREF#define Ch_0_Hysteresis				0x15 
#define Ch_0_High_Threshold_MSB		0x16 
#define Ch_0_High_Threshold_LSB		0x17 
#define Ch_0_Low_Threshold_MSB		0x18 
#define Ch_0_Low_Threshold_LSB		0x19 #define Ch_7_Hysteresis				0x38 
#define Ch_7_High_Threshold_MSB		0x39 
#define Ch_7_High_Threshold_LSB		0x3A 
#define Ch_7_Low_Threshold_MSB		0x3B 
#define Ch_7_Low_Threshold_LSB		0x3C #define Command_Read_Back		    0x3F/*******************************变量声明************************************/extern u8 Rxh[3];		//存储输出数据的高8位
extern u8 Rxl[3];		//存储输出数据的低8位extern u16 ADC1_Data[7];			//存储 ADC1 8个通道的输出数据
extern u16 ADC2_Data[7];			//存储 ADC2 8个通道的输出数据 
extern u16 ADC3_Data[7];			//存储 ADC3 8个通道的输出数据extern u16 Transfer_Data[21];		//存储3个 ADC 21个通道的输出数据/*******************************函数声明************************************/void SPI_GPIO_Init(void);
void SPI_ReadWriteByte(u8 Tx_Data, u8 *MISO1, u8 *MISO2, u8 *MISO3);			
void SPI_ReadWriteByte11(u8 Tx_Data, u8 *MISO1, u8 *MISO2, u8 *MISO3);
void ADS8688_WriteCmdReg(u16 cmd);
void Enter_AUTO_RST_Mode(void);
void ADS8688_WriteProgramRegister(u8 Addr, u8 data);
void ADS8688_ReadProgramRegister(u8 Addr);
void Set_Auto_Scan_Sequence(u8 seq);
void Set_CH_Range_Select(u8 ch, u8 range);
void Set_Channel_Power_Down(u8 pwd);
void ADS8688_Init(void);
void Get_AUTO_RST_Mode_Data(u8 chn);
void Data_Transfer(void);

函数功能

/*===============================================================
函数名称：SPI_GPIO_Init函数功能：模拟SPI端口初始化输入参数：无返 回 值：无
================================================================*/
void SPI_GPIO_Init(void)
{GPIO_InitTypeDef GPIO_InitStructure;RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB | RCC_APB2Periph_GPIOC, ENABLE);	//使能PC端口时钟GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4 | GPIO_Pin_5 | GPIO_Pin_7;	//ADS8688_CS->PA4、ADS8688_SCK->PA5、ADS8688_MOSI->PA7GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; 					//推挽输出GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;					//IO口速度为50MHzGPIO_Init(GPIOA, &GPIO_InitStructure);								//根据设定参数初始化端口GPIO_ResetBits(GPIOA,GPIO_Pin_4 | GPIO_Pin_5 | GPIO_Pin_7);			//PA4、PA5、PA7输出低电平GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;				//ADS8688_RST->PB0GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; 		//推挽输出GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;		//IO口速度为50MHz
GPIO_SetBits(GPIOB, GPIO_Pin_0);						//PB0输出高电平	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;				//ADS8688_MISO1->PA6GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;	//浮空输入	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;		//IO口速度为50MHz	GPIO_Init(GPIOA, &GPIO_InitStructure);					//根据设定参数初始化端口GPIO_ResetBits(GPIOA, GPIO_Pin_6);						//PA6输入低电平GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4 | GPIO_Pin_5;	//ADS8688_MISO2->PC4,ADS8688_MISO3->PC5GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;	//浮空输入	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;		//IO口速度为50MHz	GPIO_Init(GPIOC, &GPIO_InitStructure);					//根据设定参数初始化端口GPIO_ResetBits(GPIOC,GPIO_Pin_4 | GPIO_Pin_5);			//PC4、PC5输入低电平
}
/*===============================================================
函数名称：SPI_ReadWriteByte函数功能：模拟SPI读写8位数据，上升沿写数据，下降沿读数据输入参数：Tx_Data：写入的数据，MISO1：ADC1输出数据的指针，MISO2：ADC2输出数据的指针，MISO3：ADC3输出数据的指针返 回 值：无
================================================================*/
void SPI_ReadWriteByte(u8 Tx_Data, u8 *MISO1, u8 *MISO2, u8 *MISO3)			
{u8 i = 0;for(i = 0; i < 8; i++){ADS8688_SCK = 0;				//上升沿写入8位数据if(Tx_Data & (1 << (7 - i))){ADS8688_MOSI = 1;}else{ADS8688_MOSI = 0;}ADS8688_SCK = 1;				//下降沿读取8位数据*MISO1 <<= 1;		if(ADS8688_MISO1){*MISO1 |= 1; }*MISO2 <<= 1;if(ADS8688_MISO2){*MISO2 |= 1; }*MISO3 <<= 1;if(ADS8688_MISO3){*MISO3 |= 1; }ADS8688_SCK = 0;					          }
}
/*===============================================================
函数名称：ADS8688_WriteCmdReg函数功能：写ADS8688命令寄存器输入参数：cmd：写入的命令返 回 值：无
================================================================*/void ADS8688_WriteCmdReg(u16 cmd)
{	ADS8688_CS = 0;SPI_ReadWriteByte((cmd & 0xFF00) >> 8, Rxh, Rxh+1, Rxh+2);   SPI_ReadWriteByte(cmd & 0xFF, Rxh, Rxh+1, Rxh+2);ADS8688_CS = 1;
}
/*===============================================================
函数名称：Enter_AUTO_RST_Mode函数功能：进入AUTO_RST模式输入参数：无返 回 值：无
================================================================*/void Enter_AUTO_RST_Mode(void)
{ADS8688_WriteCmdReg(AUTO_RST);
}
/*===============================================================
函数名称：ADS8688_WriteProgramRegister函数功能：向程序寄存器中写入地址和数据输入参数：Addr：地址位：BIT[15:9]、读写位：BIT8，data：数据位：BIT[7:0]返 回 值：无
================================================================*/void ADS8688_WriteProgramRegister(u8 Addr, u8 data)
{ADS8688_CS = 0;SPI_ReadWriteByte((Addr << 1) | WRITE, Rxh, Rxh+1, Rxh+2);SPI_ReadWriteByte(data, Rxh, Rxh+1, Rxh+2);ADS8688_CS = 1;
}/*===============================================================
函数名称：ADS8688_ReadProgramRegister函数功能：读取程序寄存器中的数据输入参数：Addr：地址位：BIT[15:9]、读写位：BIT8返 回 值：data：读取的8位数据
================================================================*/void ADS8688_ReadProgramRegister(u8 Addr)
{	ADS8688_CS = 0;SPI_ReadWriteByte((Addr << 1) | READ, Rxh, Rxh+1, Rxh+2);SPI_ReadWriteByte(0xFF, Rxh, Rxh+1, Rxh+2);SPI_ReadWriteByte(0xFF, Rxh, Rxh+1, Rxh+2);			//24个SCLK周期后，可以读取8位数据ADS8688_CS = 1;
}
/*===============================================================
函数名称：Set_Auto_Scan_Sequence函数功能：设置自动扫描通道顺序输入参数：seq：所选的扫描通道返 回 值：无
================================================================*/void Set_Auto_Scan_Sequence(u8 seq)
{ADS8688_WriteProgramRegister(AUTO_SEQ_EN, seq);
}/*===============================================================
函数名称：Set_CH_Range_Select函数功能：设置通道输入范围输入参数：ch(通道地址)，可选参数：Channel_n_Input_Range,n=0-7range(输入范围)，可选参数：VREF_B_25、VREF_B_125、VREF_B_0625、VREF_U_0_25、VREF_U_0_125	
返 回 值：无                         	
==================================== ============================*/                                    
void Set_CH_Range_Select(u8 ch, u8 range) 
{                              ADS8688_WriteProgramRegister(ch, range);
}/*===============================================================
函数名称：Set_Channel_Power_Down函数功能：设置通道输入范围输入参数：pwd：0x00(通道全部上电)，0xFF(通道全部掉电)
返 回 值：无                         	
==================================== ============================*/ void Set_Channel_Power_Down(u8 pwd) 
{                              ADS8688_WriteProgramRegister(Channel_Power_Down, pwd);
}/*===============================================================
函数名称：ADS8688_Init函数功能：ADS8688初始化输入参数：无返 回 值：无
================================================================*/
void ADS8688_Init(void)
{SPI_GPIO_Init();		//模拟SPI端口初始化Set_CH_Range_Select(Channel_0_Input_Range, VREF_B_25);			//设置通道0输入范围为：±2.5×VREFSet_CH_Range_Select(Channel_1_Input_Range, VREF_B_25);			//设置通道1输入范围为：±2.5×VREFSet_CH_Range_Select(Channel_2_Input_Range, VREF_B_25);			//设置通道2输入范围为：±2.5×VREF	Set_CH_Range_Select(Channel_3_Input_Range, VREF_B_25);			//设置通道3输入范围为：±2.5×VREFSet_CH_Range_Select(Channel_4_Input_Range, VREF_B_25);			//设置通道4输入范围为：±2.5×VREFSet_CH_Range_Select(Channel_5_Input_Range, VREF_B_25);          //设置通道5输入范围为：±2.5×VREFSet_CH_Range_Select(Channel_6_Input_Range, VREF_B_25);          //设置通道6输入范围为：±2.5×VREFSet_Channel_Power_Down(0x80);	//通道0-6上电Set_Auto_Scan_Sequence(0x7F);	//自动扫描通道0-6Enter_AUTO_RST_Mode();			//进入自动扫描通道模式(具有复位功能)	                                                            
}/*===============================================================
函数名称：Get_AUTO_RST_Mode_Data函数功能：读取AUTO_RST模式下的输出数据输入参数：chn：总通道号
返 回 值：无
================================================================*/
void Get_AUTO_RST_Mode_Data(u8 chn)
{	u16 i = 0;for(i=0; i<chn; i++){ADS8688_CS = 0;SPI_ReadWriteByte(0x00, Rxh, Rxh+1, Rxh+2);		//先写后读SPI_ReadWriteByte(0x00, Rxl, Rxl+1, Rxl+2);SPI_ReadWriteByte(0xFF, Rxh, Rxh+1, Rxh+2);SPI_ReadWriteByte(0xFF, Rxl, Rxl+1, Rxl+2);SPI_ReadWriteByte(0xFF, Rxh, Rxh+1, Rxh+2);SPI_ReadWriteByte(0xFF, Rxl, Rxl+1, Rxl+2);SPI_ReadWriteByte(0xFF, Rxh, Rxh+1, Rxh+2);SPI_ReadWriteByte(0xFF, Rxl, Rxl+1, Rxl+2);ADS8688_CS = 1;ADC1_Data[i] = (Rxh[0] << 8) | Rxl[0];ADC2_Data[i] = (Rxh[1] << 8) | Rxl[1];ADC3_Data[i] = (Rxh[2] << 8) | Rxl[0];}
}
/*===============================================================
函数名称：Data_Transfer函数功能：排序输入通道输入参数：无返 回 值：无
================================================================*/
void Data_Transfer(void)
{	Transfer_Data[0] = ADC1_Data[5];		//通道1 ADC转换数据Transfer_Data[1] = ADC1_Data[4];		//通道2 ADC转换数据Transfer_Data[2] = ADC1_Data[3];		//通道3 ADC转换数据Transfer_Data[3] = ADC1_Data[2];		//通道4 ADC转换数据Transfer_Data[4] = ADC1_Data[1];		//通道5 ADC转换数据Transfer_Data[5] = ADC1_Data[0];        //通道6 ADC转换数据Transfer_Data[6] = ADC1_Data[6];		//通道7 ADC转换数据Transfer_Data[7] = ADC2_Data[5];		//通道8 ADC转换数据Transfer_Data[8] = ADC2_Data[4];        //通道9 ADC转换数据Transfer_Data[9] = ADC2_Data[3];        //通道10 ADC转换数据Transfer_Data[10] = ADC2_Data[2];       //通道11 ADC转换数据Transfer_Data[11] = ADC2_Data[1];       //通道12 ADC转换数据Transfer_Data[12] = ADC2_Data[0];       //通道13 ADC转换数据Transfer_Data[13] = ADC2_Data[6];       //通道14 ADC转换数据Transfer_Data[14] = ADC3_Data[5];		//通道15 ADC转换数据Transfer_Data[15] = ADC3_Data[4];       //通道16 ADC转换数据Transfer_Data[16] = ADC3_Data[3];       //通道17 ADC转换数据Transfer_Data[17] = ADC3_Data[2];       //通道18 ADC转换数据Transfer_Data[18] = ADC3_Data[1];       //通道19 ADC转换数据Transfer_Data[19] = ADC3_Data[0];       //通道20 ADC转换数据Transfer_Data[20] = ADC3_Data[6];       //通道21 ADC转换数据
}