a24cxx.c

用RS485通信

#include<reg51.h>
#include"IIC.h"
#include"A24CXX.h"
uchar  call[] = {0xd5,23,1,0}        ;//呼叫数据
uchar  close[] = {0xd5,26,1,0};            //关视频音频
uchar  opendoor[] = {0xd5,24,1,0};       //用户机控制门口机开门数据
uchar  danger[] = {0xd5,22,1,0};          //紧急呼叫
uchar   xying[] = {0xd5,25,1,0};          //有人应答
uchar  xian=0xd6; //空闲

//向A24CXX发送一字节数据函数：A24C_Send()
void A24C_Send(uchar temp)
{
	uchar i;
	for(i=0;i<8;i++)
	{
		PinSDA=temp&0x80;
		temp=temp<<1;
		nNop(20);
		PinSCL=1;
		nNop(20);		//SCL高电平时间不小于4uS
		PinSCL=0;		//SCL低电平时间不小于4.7uS
	}
	nNop(20);
	PinSDA=1;			//准备接收应答信号
	nNop(20);
	PinSCL=1;			//发送应答时钟
	while(PinSDA);		//判断是否有应答信号
	nNop(20);
	PinSCL=0;
	}
	
//从A24CXX读一字节数据函数：A24C_Read()
uchar A24C_Read()
{
	uchar i,temp=0;
	PinSDA=1;
	for(i=0;i<8;i++)
	{
		PinSCL=0;
		temp=temp<<1;
		PinSCL=1;
		nNop(20);
		if(PinSDA)
			temp++;
	}
	PinSCL=0;
	PinSDA=0;//应答位
	PinSCL=1;
	nNop(20);
	PinSCL=0;
	PinSDA=1;
	return(temp);
	}
	
//向A24CXX指定地址发送一字节数据函数：A24C_WriteByte()
void A24C_WriteByte(uchar DevAddr,uchar SubAddr,uchar temp)
{
	StartIIC();
	A24C_Send(DevAddr);
	A24C_Send(SubAddr);
	A24C_Send(temp);
	StopIIC();
	LongDelay(2);
	}

//从A24CXX指定地址接收一字节数据函数：A24C_ReadByte()
uchar A24C_ReadByte(uchar DevAddr,uchar SubAddr)
{
	uchar temp;
	StartIIC();
	A24C_Send(DevAddr);
	A24C_Send(SubAddr);
	StopIIC();
	StartIIC();
	A24C_Send(DevAddr+1);
	temp = A24C_Read();
	StopIIC();
	LongDelay(2);
	return(temp);
	}

//向A24CXX中预存入数据函数：WriteEErom()
void WriteEErom()
{
	uchar i,j;
	do{
		StartIIC();
		A24C_Send(A24C02);
		A24C_Send(j);
		for(i=0;i<8;i++)
			A24C_Send(i+j);
		StopIIC();
		for(i=0;i<255;i++)
			nNop(10);
		j=j+8;
		}while(j!=0);
}	


void chushuju()
{
 A24C_WriteByte(0xa0,0x00,xian);
 A24C_WriteByte(0xa0,0x01,call[0]);
 A24C_WriteByte(0xa0,0x02,call[1]);
 A24C_WriteByte(0xa0,0x03,call[2]);
 A24C_WriteByte(0xa0,0x04,call[3]);

 A24C_WriteByte(0xa0,0x05,close[0]);
 A24C_WriteByte(0xa0,0x06,close[1]);
 A24C_WriteByte(0xa0,0x07,close[2]);
 A24C_WriteByte(0xa0,0x08,close[3]);

 A24C_WriteByte(0xa0,0x09,opendoor[0]);
 A24C_WriteByte(0xa0,0x0a,opendoor[1]);
 A24C_WriteByte(0xa0,0x0b,opendoor[2]); 
 A24C_WriteByte(0xa0,0x0c,opendoor[3]);

 A24C_WriteByte(0xa0,0x0d,danger[0]);
 A24C_WriteByte(0xa0,0x0e,danger[1]);
 A24C_WriteByte(0xa0,0x0f,danger[2]);
 A24C_WriteByte(0xa0,0x10,danger[3]);

 A24C_WriteByte(0xa0,0x11,xying[0]);
 A24C_WriteByte(0xa0,0x12,xying[1]);
 A24C_WriteByte(0xa0,0x13,xying[2]);
 A24C_WriteByte(0xa0,0x14,xying[3]);

}