单片机普通IO口模拟IIC多机通信,本人已测试通过

1、/* 说明，该程序是模拟IIC的通信思想，但也不全是，首先本人设计的不是从机与主机的通信，而是两单片机是平等的，单片机A可以向B或其他任何单片机发送数据（通过各个单片机所设置的地址来加以区分），同时单片机A可以也向B或其他任何单片机读取数据。反之单片机B或其他单片机也可以向A发送数据或读取A的数据，所以各个单片机的代码基本上是一样的，只需根据具体不同的需要调用就行。 由于本人初学单片机，代码写的并不是很好。望各位多多指教！*/单片机A 的代码#include<reg52.h>#define uchar unsigned char#define uint unsigned int#d

2、efine LOC_address 0x48sbit sda=P10;sbit scl=P11;sbit STROBE = P12;bit R_W;bit START_flag=0;uchar DEV_address;void delay() uint i; for(i=0;i<=100;i+);void init() sda=1; scl=1; STROBE=1; void start() /启动I2C总线 sda = 1; delay(); scl = 1; delay(); sda = 0; delay(); /此处scl不能拉低，否则两单片机通信时时序无法保持一致 /*void

3、start_scan() bit PreState;bit NowState; char NN = 10;PreState = sda;/记录当前SDA状态，用作比较while(scl = 1 && NN-)NowState = sda;if(PreState = 1 && NowState = 0)/如果为下降沿则为开始信号 START_flag = 1; */void Send_Date(uchar j) unsigned char i;bit temp; scl = 1;while(STROBE);if(STROBE=0) delay(); delay()

4、;delay(); for (i = 0 ;i < 8 ;i+) if(j<<i)&0x80)temp=1; else temp=0;sda = temp; 、delay(); scl = 0; delay(); scl = 1; delay(); scl = 0;sda = 1; /释放数据线 delay();STROBE=1; STROBE=1;uchar Receive_Date() uchar i,j,k=0xff; scl = 1; STROBE=0; delay(); if(!scl)&&(sda) return k; if(STROBE=

5、0) while(scl); for(i=0;i<8;i+) while(!scl);if(sda=1) j=1; else j=0; k=(k<<1)|j; delay(); delay();while(scl); P2=k; return k; return k;/*void ChackRdd() uchar i,j,k=0xff; scl = 1; STROBE=0; delay(); if(!STROBE) while(scl); for(i=0;i<8;i+) while(!scl);if(sda=1) j=1; else j=0; k=(k<<1

6、)|j; delay(); delay();while(scl); P0=k; R_W=k&0x01; DEV_address=(k&0xfe); STROBE=1; STROBE=1;void B_work()if(STROBE) ChackRdd(); if(DEV_address=LOC_address) if(R_W) STROBE=(STROBE); Send_Date(0x55); else if(!R_W) STROBE=(STROBE); Receive_Date(); */void main() init(); while(1)/以下为测试代码。 while(

7、STROBE) while(STROBE) start(); while(!STROBE);/*while(STROBE) Send_Date(0xaa);/发送地址和写指令 while(!STROBE) Send_Date(0x99); /发送数据 0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90*/while(STROBE) Send_Date(0xab); /发送地址和读指令 while(!STROBE) STROBE=1; Receive_Date(); /单片机B的代码#include<reg52.h>#define uc

8、har unsigned char#define uint unsigned int#define LOC_address 0xaasbit sda=P10;sbit scl=P11;sbit STROBE = P12;bit R_W;bit START_flag=0;uchar DEV_address;void delay() uint i; for(i=0;i<=100;i+);/*void start() /启动I2C总线 sda = 1; delay(); scl = 1; delay(); sda = 0; delay(); */void start_scan() bit Pr

9、eState;bit NowState; char NN = 10;PreState = sda;/记录当前SDA状态，用作比较while(scl = 1 && NN-)NowState = sda;if(PreState = 1 && NowState = 0)/如果为下降沿则为开始信号 START_flag = 1;void Send_Date(uchar j) unsigned char i;bit temp; scl = 1;while(STROBE);if(STROBE=0) delay(); delay();delay(); for (i = 0 ;

10、i < 8 ;i+) if(j<<i)&0x80)temp=1; else temp=0;sda = temp; delay(); scl = 0; delay(); scl = 1; delay(); scl = 0;sda = 1; /释放数据线 delay();STROBE=1; STROBE=1;uchar Receive_Date() uchar i,j,k=0xff; scl = 1; STROBE=0; delay(); if(!scl)&&(sda) return k; if(STROBE=0) while(scl); for(i=0;

11、i<8;i+) while(!scl);if(sda=1) j=1; else j=0; k=(k<<1)|j; delay(); delay();while(scl); P2=k; return k; return k;void ChackRdd() uchar i,j,k=0xff; scl = 1; STROBE=0;/置低信号告诉单片机A、单片机B已做好准备接收 delay(); if(!STROBE) while(scl);/等待A响应 for(i=0;i<8;i+) while(!scl);if(sda=1) j=1; else j=0; k=(k<<1)|j; delay(); delay();while(scl); P0=k; R_W=k&0x01; DEV_address=(k&0xfe); STROBE=1; STROBE=1;void B_work() if(STROBE) start_scan(); if(START_flag) START_flag=0; STROBE=0; delay(); STROBE=1; ChackRdd(); if(DEV_address=LOC_