单片机DA转换实现正弦波
使用的是查表法:
1.c文件:
#include "reg52.h" #include <intrins.h> #include <i2c.h> #define PCF8591 0x90 #define uint unsigned int #define uchar unsigned char #define arr_length 720 //正弦波数组长度 code unsigned char sin1[720]={0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x8a,0x8b,0x8c,0x8d,0x8e, 0x8f,0x90,0x91,0x92,0x94,0x95,0x96,0x97,0x98,0x99,0x9a,0x9b,0x9c,0x9d,0x9e,0xa0,0xa1,0xa2,0xa3,0xa4, 0xa5,0xa6,0xa7,0xa8,0xa9,0xaa,0xab,0xac,0xad,0xae,0xaf,0xb0,0xb2,0xb3,0xb4,0xb5,0xb6,0xb7,0xb8,0xb9, 0xba,0xbb,0xbc,0xbd,0xbe,0xbf,0xbf,0xc0,0xc1,0xc2,0xc3,0xc4,0xc5,0xc6,0xc7,0xc8,0xc9,0xca,0xcb,0xcc, 0xcd,0xcd,0xce,0xcf,0xd0,0xd1,0xd2,0xd3,0xd3,0xd4,0xd5,0xd6,0xd7,0xd8,0xd8,0xd9,0xda,0xdb,0xdc,0xdc, 0xdd,0xde,0xdf,0xdf,0xe0,0xe1,0xe2,0xe2,0xe3,0xe4,0xe4,0xe5,0xe6,0xe6,0xe7,0xe8,0xe8,0xe9,0xea,0xea, 0xeb,0xeb,0xec,0xed,0xed,0xee,0xee,0xef,0xef,0xf0,0xf1,0xf1,0xf2,0xf2,0xf3,0xf3,0xf4,0xf4,0xf4,0xf5, 0xf5,0xf6,0xf6,0xf7,0xf7,0xf7,0xf8,0xf8,0xf9,0xf9,0xf9,0xfa,0xfa,0xfa,0xfb,0xfb,0xfb,0xfb,0xfc,0xfc, 0xfc,0xfc,0xfd,0xfd,0xfd,0xfd,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xff,0xff,0xff,0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfd,0xfd,0xfd,0xfd,0xfc,0xfc,0xfc,0xfc,0xfb,0xfb, 0xfb,0xfb,0xfa,0xfa,0xfa,0xf9,0xf9,0xf9,0xf8,0xf8,0xf7,0xf7,0xf7,0xf6,0xf6,0xf5,0xf5,0xf4,0xf4, 0xf4,0xf3,0xf3,0xf2,0xf2,0xf1,0xf1,0xf0,0xef,0xef,0xee,0xee,0xed,0xed,0xec,0xeb,0xeb,0xea,0xea, 0xe9,0xe8,0xe8,0xe7,0xe6,0xe6,0xe5,0xe4,0xe4,0xe3,0xe2,0xe2,0xe1,0xe0,0xdf,0xdf,0xde,0xdd,0xdc, 0xdc,0xdb,0xda,0xd9,0xd8,0xd8,0xd7,0xd6,0xd5,0xd4,0xd3,0xd3,0xd2,0xd1,0xd0,0xcf,0xce,0xcd,0xcd, 0xcc,0xcb,0xca,0xc9,0xc8,0xc7,0xc6,0xc5,0xc4,0xc3,0xc2,0xc1,0xc0,0xc0,0xbf,0xbe,0xbd,0xbc,0xbb, 0xba,0xb9,0xb8,0xb7,0xb6,0xb5,0xb4,0xb3,0xb2,0xb0,0xaf,0xae,0xad,0xac,0xab,0xaa,0xa9,0xa8,0xa7, 0xa6,0xa5,0xa4,0xa3,0xa2,0xa1,0xa0,0x9e,0x9d,0x9c,0x9b,0x9a,0x99,0x98,0x97,0x96,0x95,0x94,0x92, 0x91,0x90,0x8f,0x8e,0x8d,0x8c,0x8b,0x8a,0x88,0x87,0x86,0x85,0x84,0x83,0x82,0x81,0x80,0x7e,0x7d, 0x7c,0x7b,0x7a,0x79,0x78,0x77,0x75,0x74,0x73,0x72,0x71,0x70,0x6f,0x6e,0x6d,0x6b,0x6a,0x69,0x68, 0x67,0x66,0x65,0x64,0x63,0x62,0x61,0x5f,0x5e,0x5d,0x5c,0x5b,0x5a,0x59,0x58,0x57,0x56,0x55,0x54, 0x53,0x52,0x51,0x50,0x4f,0x4d,0x4c,0x4b,0x4a,0x49,0x48,0x47,0x46,0x45,0x44,0x43,0x42,0x41,0x40, 0x40,0x3f,0x3e,0x3d,0x3c,0x3b,0x3a,0x39,0x38,0x37,0x36,0x35,0x34,0x33,0x32,0x32,0x31,0x30,0x2f, 0x2e,0x2d,0x2c,0x2c,0x2b,0x2a,0x29,0x28,0x27,0x27,0x26,0x25,0x24,0x23,0x23,0x22,0x21,0x20,0x20, 0x1f,0x1e,0x1d,0x1d,0x1c,0x1b,0x1b,0x1a,0x19,0x19,0x18,0x17,0x17,0x16,0x15,0x15,0x14,0x14,0x13, 0x12,0x12,0x11,0x11,0x10,0x10,0xf,0xe,0xe,0xd,0xd,0xc,0xc,0xb,0xb,0xb,0xa,0xa,0x9,0x9,0x8,0x8, 0x8,0x7,0x7,0x6,0x6,0x6,0x5,0x5,0x5,0x4,0x4,0x4,0x4,0x3,0x3,0x3,0x3,0x2,0x2,0x2,0x2,0x1,0x1,0x1, 0x1,0x1,0x1,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0, 0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x1,0x1,0x1,0x1,0x1,0x1,0x2,0x2,0x2,0x2,0x3,0x3,0x3,0x3,0x4,0x4, 0x4,0x4,0x5,0x5,0x5,0x6,0x6,0x6,0x7,0x7,0x8,0x8,0x8,0x9,0x9,0xa,0xa,0xb,0xb,0xb,0xc,0xc,0xd,0xd, 0xe,0xe,0xf,0x10,0x10,0x11,0x11,0x12,0x12,0x13,0x14,0x14,0x15,0x15,0x16,0x17,0x17,0x18,0x19,0x19, 0x1a,0x1b,0x1b,0x1c,0x1d,0x1d,0x1e,0x1f,0x20,0x20,0x21,0x22,0x23,0x23,0x24,0x25,0x26,0x27,0x27, 0x28,0x29,0x2a,0x2b,0x2c,0x2c,0x2d,0x2e,0x2f,0x30,0x31,0x32,0x32,0x33,0x34,0x35,0x36,0x37,0x38, 0x39,0x3a,0x3b,0x3c,0x3d,0x3e,0x3f,0x3f,0x40,0x41,0x42,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4a, 0x4b,0x4c,0x4d,0x4f,0x50,0x51,0x52,0x53,0x54,0x55,0x56,0x57,0x58,0x59,0x5a,0x5b,0x5c,0x5d,0x5e, 0x5f,0x61,0x62,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6a,0x6b,0x6d,0x6e,0x6f,0x70,0x71,0x72,0x73, 0x74,0x75,0x77,0x78,0x79,0x7a,0x7b,0x7c,0x7d,0x7e}; uchar code sin2[256]={ 0x80, 0x83, 0x86, 0x89, 0x8c, 0x8f, 0x92, 0x95, 0x98, 0x9c, 0x9f, 0xa2, 0xa5, 0xa8, 0xab, 0xae, 0xb0, 0xb3, 0xb6, 0xb9, 0xbc, 0xbf, 0xc1, 0xc4, 0xc7, 0xc9, 0xcc, 0xce, 0xd1, 0xd3, 0xd5, 0xd8, 0xda, 0xdc, 0xde, 0xe0, 0xe2, 0xe4, 0xe6, 0xe8, 0xea, 0xec, 0xed, 0xef, 0xf0, 0xf2, 0xf3, 0xf4, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfc, 0xfd, 0xfe, 0xfe, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe, 0xfe, 0xfd, 0xfc, 0xfc, 0xfb, 0xfa, 0xf9, 0xf8, 0xf7, 0xf6, 0xf5, 0xf3, 0xf2, 0xf0, 0xef, 0xed, 0xec, 0xea, 0xe8, 0xe6, 0xe4, 0xe3, 0xe1, 0xde, 0xdc, 0xda, 0xd8, 0xd6, 0xd3, 0xd1, 0xce, 0xcc, 0xc9, 0xc7, 0xc4, 0xc1, 0xbf, 0xbc, 0xb9, 0xb6, 0xb4, 0xb1, 0xae, 0xab, 0xa8, 0xa5, 0xa2, 0x9f, 0x9c, 0x99, 0x96, 0x92, 0x8f, 0x8c, 0x89, 0x86, 0x83, 0x80, 0x7d, 0x79, 0x76, 0x73, 0x70, 0x6d, 0x6a, 0x67, 0x64, 0x61, 0x5e, 0x5b, 0x58, 0x55, 0x52, 0x4f, 0x4c, 0x49, 0x46, 0x43, 0x41, 0x3e, 0x3b, 0x39, 0x36, 0x33, 0x31, 0x2e, 0x2c, 0x2a, 0x27, 0x25, 0x23, 0x21, 0x1f, 0x1d, 0x1b, 0x19, 0x17, 0x15, 0x14, 0x12, 0x10, 0x0f, 0x0d, 0x0c, 0x0b, 0x09, 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x03, 0x02, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x02, 0x03, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0c, 0x0d, 0x0e, 0x10, 0x12, 0x13, 0x15, 0x17, 0x18, 0x1a, 0x1c, 0x1e, 0x20, 0x23, 0x25, 0x27, 0x29, 0x2c, 0x2e, 0x30, 0x33, 0x35, 0x38, 0x3b, 0x3d, 0x40, 0x43, 0x46, 0x48, 0x4b, 0x4e, 0x51, 0x54, 0x57, 0x5a, 0x5d, 0x60, 0x63, 0x66, 0x69, 0x6c, 0x6f, 0x73, 0x76, 0x79, 0x7c, }; sbit key1=P3^4; sbit key2=P3^5; uint speed=20; //正弦波变化速度 uint num=0; uint time=0; DACconversion(unsigned char sla,unsigned char c, unsigned char Val); void Init_Timer1(void)//定时器一初始化程序 { TMOD=0x01; TH0=(65535-0)/256; TL0=(65535-0)%256; EA=1;//开总中断 ET0=1;//开定时器0中断 TR0=1; //启动定时器0 } void delay(uchar s){ uchar i,j; for(i=s;i>0;i--) for(j=110;j>0;j--); } void change_Speed(){ if(key1==0){ delay(10); if(key1==0){ speed++; } } if(key2==0){ delay(10); if(key2==0){ if(speed>1) speed--; } } } void time0() interrupt 1{ TH0=(65535-0)/256; TL0=(65535-0)%256; change_Speed(); for(num=0;num<arr_length;num=num+speed){ DACconversion(PCF8591,0x40,sin1[num]); } if(num==arr_length){ num=0; } } void main() { Init_Timer1(); }
i2c.c文件
/*----------------------------------------------- 名称:IIC协议 修改:无 内容:函数是采用软件延时的方法产生SCL脉冲,固对高晶振频率要作 一定的修改....(本例是1us机器 周期,即晶振频率要小于12MHZ) ------------------------------------------------*/ #include "i2c.h" //#include "delay.h" #define PCF8591 0x90 #define _Nop() _nop_() //定义空指令 bit ack; //应答标志位 sbit SDA=P2^0; sbit SCL=P2^1; /*------------------------------------------------ 启动总线 ------------------------------------------------*/ void Start_I2c() { SDA=1; //发送起始条件的数据信号 _Nop(); SCL=1; _Nop(); //起始条件建立时间大于4.7us,延时 _Nop(); _Nop(); _Nop(); _Nop(); SDA=0; //发送起始信号 _Nop(); //起始条件锁定时间大于4μ _Nop(); _Nop(); _Nop(); _Nop(); SCL=0; //钳住I2C总线,准备发送或接收数据 _Nop(); _Nop(); } /*------------------------------------------------ 结束总线 ------------------------------------------------*/ void Stop_I2c() { SDA=0; //发送结束条件的数据信号 _Nop(); //发送结束条件的时钟信号 SCL=1; //结束条件建立时间大于4μ _Nop(); _Nop(); _Nop(); _Nop(); _Nop(); SDA=1; //发送I2C总线结束信号 _Nop(); _Nop(); _Nop(); _Nop(); } /*---------------------------------------------------------------- 字节数据传送函数 函数原型: void SendByte(unsigned char c); 功能: 将数据c发送出去,可以是地址,也可以是数据,发完后等待应答,并对 此状态位进行操作.(不应答或非应答都使ack=0 假) 发送数据正常,ack=1; ack=0表示被控器无应答或损坏。 ------------------------------------------------------------------*/ void SendByte(unsigned char c) { unsigned char BitCnt; for(BitCnt=0;BitCnt<8;BitCnt++) //要传送的数据长度为8位 { if((c<<BitCnt)&0x80)SDA=1; //判断发送位 else SDA=0; _Nop(); SCL=1; //置时钟线为高,通知被控器开始接收数据位 _Nop(); _Nop(); //保证时钟高电平周期大于4μ _Nop(); _Nop(); _Nop(); SCL=0; } _Nop(); _Nop(); SDA=1; //8位发送完后释放数据线,准备接收应答位 _Nop(); _Nop(); SCL=1;//控制线 _Nop(); _Nop(); _Nop(); if(SDA==1)ack=0; else ack=1; //判断是否接收到应答信号 SCL=0; _Nop(); _Nop(); } /******************************************************************* DAC变换,转化函数 *******************************************************************/ bit DACconversion(unsigned char sla,unsigned char c, unsigned char Val) { Start_I2c();//启动总线 SendByte(sla);//发送器件地址 if(ack==0)return(0); SendByte(c);//发送控制字节 if(ack==0)return(0); SendByte(Val);//发送DAC的数值 if(ack==0)return(0); Stop_I2c();//结束总线 return(1); } /*---------------------------------------------------------------- 字节数据传送函数 函数原型: unsigned char RcvByte(); 功能: 用来接收从器件传来的数据,并判断总线错误(不发应答信号), 发完后请用应答函数。 ------------------------------------------------------------------*/ /*unsigned char RcvByte() { unsigned char retc; unsigned char BitCnt; retc=0; SDA=1; //置数据线为输入方式 for(BitCnt=0;BitCnt<8;BitCnt++) { _Nop(); SCL=0; //置时钟线为低,准备接收数据位 _Nop(); _Nop(); //时钟低电平周期大于4.7us _Nop(); _Nop(); _Nop(); SCL=1; //置时钟线为高使数据线上数据有效 _Nop(); _Nop(); retc=retc<<1; if(SDA==1)retc=retc+1; //读数据位,接收的数据位放入retc中 _Nop(); _Nop(); } SCL=0; _Nop(); _Nop(); return(retc); } */ /*---------------------------------------------------------------- 应答子函数 原型: void Ack_I2c(void); ----------------------------------------------------------------*/ /*void Ack_I2c(void) { SDA=0; _Nop(); _Nop(); _Nop(); SCL=1; _Nop(); _Nop(); //时钟低电平周期大于4μ _Nop(); _Nop(); _Nop(); SCL=0; //清时钟线,钳住I2C总线以便继续接收 _Nop(); _Nop(); }*/ /*---------------------------------------------------------------- 非应答子函数 原型: void NoAck_I2c(void); ----------------------------------------------------------------*/ /*void NoAck_I2c(void) { SDA=1; _Nop(); _Nop(); _Nop(); SCL=1; _Nop(); _Nop(); //时钟低电平周期大于4μ _Nop(); _Nop(); _Nop(); SCL=0; //清时钟线,钳住I2C总线以便继续接收 _Nop(); _Nop(); } */ /*---------------------------------------------------------------- 向无子地址器件发送字节数据函数 函数原型: bit ISendByte(unsigned char sla,ucahr c); 功能: 从启动总线到发送地址,数据,结束总线的全过程,从器件地址sla. 如果返回1表示操作成功,否则操作有误。 注意: 使用前必须已结束总线。 ----------------------------------------------------------------*/ /*bit ISendByte(unsigned char sla,unsigned char c) { Start_I2c(); //启动总线 SendByte(sla); //发送器件地址 if(ack==0)return(0); SendByte(c); //发送数据 if(ack==0)return(0); Stop_I2c(); //结束总线 return(1); } */ /*---------------------------------------------------------------- 向有子地址器件发送多字节数据函数 函数原型: bit ISendStr(unsigned char sla,unsigned char suba,ucahr *s,unsigned char no); 功能: 从启动总线到发送地址,子地址,数据,结束总线的全过程,从器件 地址sla,子地址suba,发送内容是s指向的内容,发送no个字节。 如果返回1表示操作成功,否则操作有误。 注意: 使用前必须已结束总线。 ----------------------------------------------------------------*/ /*bit ISendStr(unsigned char sla,unsigned char suba,unsigned char *s,unsigned char no) { unsigned char i; for(i=0;i<no;i++) { Start_I2c(); //启动总线 SendByte(sla); //发送器件地址 if(ack==0)return(0); SendByte(suba); //发送器件子地址 if(ack==0)return(0); SendByte(*s); //发送数据 if(ack==0)return(0); Stop_I2c(); //结束总线 DelayMs(1); //必须延时等待芯片内部自动处理数据完毕 s++; suba++; } return(1); } */ /*---------------------------------------------------------------- 向无子地址器件读字节数据函数 函数原型: bit IRcvByte(unsigned char sla,ucahr *c); 功能: 从启动总线到发送地址,读数据,结束总线的全过程,从器件地 址sla,返回值在c. 如果返回1表示操作成功,否则操作有误。 注意: 使用前必须已结束总线。 ----------------------------------------------------------------*/ /*bit IRcvByte(unsigned char sla,unsigned char *c) { Start_I2c(); //启动总线 SendByte(sla+1); //发送器件地址 if(ack==0)return(0); *c=RcvByte(); //读取数据 NoAck_I2c(); //发送非就答位 Stop_I2c(); //结束总线 return(1); } */ /*---------------------------------------------------------------- 向有子地址器件读取多字节数据函数 函数原型: bit ISendStr(unsigned char sla,unsigned char suba,ucahr *s,unsigned char no); 功能: 从启动总线到发送地址,子地址,读数据,结束总线的全过程,从器件 地址sla,子地址suba,读出的内容放入s指向的存储区,读no个字节。 如果返回1表示操作成功,否则操作有误。 注意: 使用前必须已结束总线。 ----------------------------------------------------------------*/ /*bit IRcvStr(unsigned char sla,unsigned char suba,unsigned char *s,unsigned char no) { unsigned char i; Start_I2c(); //启动总线 SendByte(sla); //发送器件地址 if(ack==0)return(0); SendByte(suba); //发送器件子地址 if(ack==0)return(0); Start_I2c(); SendByte(sla+1); if(ack==0)return(0); for(i=0;i<no-1;i++) { *s=RcvByte(); //发送数据 Ack_I2c(); //发送就答位 s++; } *s=RcvByte(); NoAck_I2c(); //发送非应位 Stop_I2c(); //结束总线 return(1); } */
原理图:
效果:
单片机课程设计~