pcf8591用途（PCF8591模数与数模转换实验）

pcf8591用途（PCF8591模数与数模转换实验）

一，源代码 /*************** ying悦1SD ******************/ #include <reg52.h> #include <intrins.h> #define uint unsigned int #define uchar unsigned char #define Delay4us() {_nop_();_nop_();_nop_();_nop_();} sbit LCD_RS = P2^0; sbit LCD_RW = P2^1; sbit LCD_EN = P2^2; sbit SCL = P1^0; sbit SDA = P1^1; uchar Recv_Buffer[4]; uint Voltage[]={'0' '0' '0' '0'}; bit bdata IIC_ERROR; uchar LCD_Line_1[] = {"1- . V 2- . V"}; uchar LCD_Line_2[] = {"3- . V 4- . V"}; void Delay(uint ms) { uchar i; while(ms--) { for(i=0;i<120;i ); } } bit LCD_Busy_Check() { bit Result; LCD_RS = 0; LCD_RW = 1; LCD_EN = 1; Delay4us(); Result = (bit)(P0&0x80); LCD_EN = 0; return Result; } void LCD_Write_Command(uchar cmd) { while(LCD_Busy_Check()); LCD_RS = 0; LCD_RW = 0; LCD_EN = 0; _nop_(); _nop_(); P0 = cmd; Delay4us(); LCD_EN = 1; Delay4us(); LCD_EN = 0; } void LCD_Write_Data(uchar dat) { while(LCD_Busy_Check()); LCD_RS = 1; LCD_RW = 0; LCD_EN = 0; P0 = dat; Delay4us(); LCD_EN = 1; Delay4us(); LCD_EN = 0; } void LCD_Initialise() { LCD_Write_Command(0x38);Delay(5); LCD_Write_Command(0x0c);Delay(5); LCD_Write_Command(0x06);Delay(5); LCD_Write_Command(0x01);Delay(5); } void LCD_Set_Position(uchar pos) { LCD_Write_Command(pos | 0x80); } void LCD_Display_A_Line(uchar Line_Addr uchar s[]) { uchar i; LCD_Set_Position(Line_Addr); for(i=0;i<16;i ) { LCD_Write_Data(s[i]); } } void Convert_To_Voltage(uchar val) { uchar Tmp; Voltage[2] = val/51 '0'; Tmp = valQ*10; Voltage[1] = Tmp/51 '0'; Tmp = TmpQ*10; Voltage[0] = Tmp/51 '0'; } void IIC_Start() { SDA = 1; SCL = 1; Delay4us(); SDA = 0; Delay4us(); SCL = 0; } void IIC_Stop() { SDA = 0; SCL = 1; Delay4us(); SDA = 1; Delay4us(); SCL = 0; } void Slave_ACK() { SDA = 0; SCL = 1; Delay4us(); SCL = 0; SDA = 1; } void Slave_NOACK() { SDA = 1; SCL = 1; Delay4us(); SCL = 0; SDA = 0; } void IIC_SendByte(uchar wd) { uchar i; for(i=0;i<8;i ) { SDA=(bit)(wd&0x80); _nop_(); _nop_(); SCL = 1; Delay4us(); } Delay4us(); SDA = 1; SCL = 1; Delay4us(); IIC_ERROR = SDA; SCL = 0; Delay4us(); } uchar IIC_ReceiveByte() { uchar i rd = 0x00; for(i=0;i<8;i ) { SCL = 1; rd <<= 1; rd |= SDA; Delay4us(); SCL = 0; Delay4us(); } SCL = 0; Delay4us(); return rd; } void ADC_PCF8591(uchar CtrlByte) { uchar i; IIC_Start(); IIC_SendByte(0x90); if(IIC_ERROR == 1) return; IIC_SendByte(CtrlByte); if(IIC_ERROR == 1) return; IIC_Start(); IIC_SendByte(0x91); if(IIC_ERROR == 1) return; IIC_ReceiveByte(); Slave_ACK(); for(i=0;i<4;i ) { Recv_Buffer[i ] = IIC_ReceiveByte(); Slave_ACK(); } Slave_NOACK(); IIC_Stop(); } void DAC_PCF8591(uchar CtrlByte uchar dat) { IIC_Start(); Delay4us(); IIC_SendByte(0x90); if(IIC_ERROR == 1) return; IIC_SendByte(CtrlByte); if(IIC_ERROR == 1) return; IIC_SendByte(dat); if(IIC_ERROR == 1) return; IIC_Stop(); Delay4us(); Delay4us(); } void main() { LCD_Initialise(); while(1) { ADC_PCF8591(0x40); Convert_To_Voltage(Recv_Buffer[0]); LCD_Line_1[2]=Voltage[2]; LCD_Line_1[4]=Voltage[1]; LCD_Line_1[5]=Voltage[0]; Convert_To_Voltage(Recv_Buffer[1]); LCD_Line_1[11]=Voltage[2]; LCD_Line_1[13]=Voltage[1]; LCD_Line_1[14]=Voltage[0]; Convert_To_Voltage(Recv_Buffer[2]); LCD_Line_2[2]=Voltage[2]; LCD_Line_2[4]=Voltage[1]; LCD_Line_2[5]=Voltage[0]; Convert_To_Voltage(Recv_Buffer[3]); LCD_Line_2[11]=Voltage[2]; LCD_Line_2[13]=Voltage[1]; LCD_Line_2[14]=Voltage[0]; LCD_Display_A_Line(0x00 LCD_Line_1); LCD_Display_A_Line(0x40 LCD_Line_2); DAC_PCF8591(0x40 Recv_Buffer[0]); } } 二，仿真