readtime.c

时钟芯片8563读写程序,C51单片机控制,很好用的.

#include <52.h>

#define READ 0xa3
#define WRITE 0xa2

extern sbit SDA = P1^6;//时钟芯片数据线
extern sbit SCL = P1^7;//时钟芯片时钟线

extern byte idata second, minute, hour, week, day, month, year;
extern word idata date, time, dn_date, dn_time;//从控制器下载的时间暂存储变量
extern word code monthday[];
void wr_time(void);			//写时间到8563
void byt_to_time(void);		//计算时间	
void rd_time(void);			//从8563读时间
void time_to_byt(void);		//计算时间	
void delay_iic(void);
void rd_time(void);	//从时间芯片中读时间到second,minute,hour,week等变量中			
//extern void Delay(unsigned int j);//延时US

                      
  
void delay_iic(void)
{
	byte i;
	for(i = 0; i < 5; i++);
}

void I_start(void)//启动I2C
{
	SDA = 1;
	SCL = 1;
	delay_iic();
	SDA = 0;
	delay_iic();
	SCL = 0;
}

void I_stop(void)//I2C停止
{
	SDA = 0;
	SCL = 1;
	delay_iic();
	SDA = 1;
}

byte I_WaitAck(void)//等待应答
{
	bit ack;

	SDA = 1;
	delay_iic();
	SCL = 1;
	delay_iic();
	ack = SDA;
	SCL = 0;

	if(ack) return 0;
	else return 1;
}

void I_Ack(void)//I2C应答
{
	SDA = 1;
	delay_iic();
	SCL = 1;
	delay_iic();
	SCL = 0;
	delay_iic();
	SDA = 0;
}

void I_send(byte i_data)//I2C发送数据
{
	byte i;

	for(i = 0; i < 8; i++)
	{
		SDA = (bit)(i_data & 0x80);
		i_data = i_data << 1;
		SCL = 1;
		delay_iic();
		SCL = 0;
	}
	SDA = 1;
}

byte I_receive(void)//I2C接收数据
{
	byte i;
	byte i_data = 0;
	bit rdata;
	
	SDA = 1;

	for(i = 0; i < 8; i++)
	{	
		SCL = 1;
		i_data *= 2;
		rdata = SDA;
		if(rdata) i_data++;
		SCL = 0;
	}
	return i_data;
}

void I_Write(byte address, byte i_data)//写时间芯片
{
	I_start();
	I_send(WRITE);
	I_WaitAck();
	I_send(address);
	I_WaitAck();
	I_send(i_data);
	I_WaitAck();
	I_stop();
}

byte I_Read(byte address)//读时间芯片
{
	byte i_data;

	I_start();
	I_send(WRITE);
	I_WaitAck();
	I_send(address);
	I_WaitAck();

	I_start();
	I_send(READ);
	I_WaitAck();
	i_data = I_receive();
	I_Ack();
	I_stop();
	
	return i_data;
}


void wr_time(void)		////更新8563时间
{
	byte tmp;

	tmp = second/10 * 16 + second%10;
	I_Write(2, tmp);
	tmp = minute/10 * 16 + minute%10;
	I_Write(3, tmp);
	tmp = hour/10 * 16 + hour%10;
	I_Write(4, tmp);

	tmp = week/10 *16 + week%10;
	I_Write(6, tmp);
	tmp = day/10 * 16 + day%10;
	I_Write(5, tmp);
	tmp = month/10 * 16 + month%10;
	I_Write(7, tmp);
	tmp = year/10 * 16 + year%10;
	I_Write(8, tmp);
}

void byt_to_time(void)		//把下载的时间计算后放到dyear等变量中	
{
	word tmp, md;
	byte temp, i;

	year = dn_date / 1461;
	year *= 4;
	tmp = dn_date % 1461;
	if(tmp >= 1096)
	{
		year += 3;
		tmp -= 1096;
    	}
	else if(tmp >= 731)
	{
		year += 2;
		tmp -= 731;
	}
	else if(tmp >= 366)
	{
		year += 1;
		tmp -= 366;
	}
	if((year & 3) == 0)
		temp = 1;
	else 
		temp = 0;
	month = 0;
	i = 0;
	while(i == 0)
	{
		md = monthday[month];
		month += 1;
		if((temp != 0) && (month == 2))
			md += 1;
		if(tmp >= md)
			tmp -= md;
		else 
			i = 1;
	}
	day = (byte)(tmp + 1);
	week = (dn_date + 6) % 7;

	hour = dn_time / 1800;
	minute = (dn_time % 1800) / 30;
	second = ((dn_time % 1800) % 30) * 2; 
}
void rd_time(void)	//从时间芯片中读时间到second,minute,hour,week等变量中			
{
	byte tmp;

	tmp = I_Read(0x02);
	tmp &= 0x7f;
	second = tmp/16 * 10 + tmp%16;	//BCD码转换成16进制

	tmp = I_Read(0x03);
	tmp &= 0x7f;
	minute = tmp/16 * 10 + tmp%16;

	tmp = I_Read(0x04);
	tmp &= 0x3f;
	hour = tmp/16 * 10 + tmp%16;

	tmp = I_Read(0x06);
	tmp &= 0x07;
	week = tmp/16 * 10 + tmp%16;
	
	tmp = I_Read(0x05);
	tmp &= 0x3f;
	day = tmp/16 * 10 + tmp%16;
	
	tmp = I_Read(0x07);
	tmp &= 0x1f;
	month = tmp/16 * 10 + tmp%16;
	
	tmp = I_Read(0x08);
	tmp &= 0x7f;
	year = tmp/16 * 10 + tmp%16;
}

void time_to_byt(void)			
{
	byte tmp;
	word t_da, t_ti;

	tmp = year / 4;
	t_da = tmp * 1461;		//每4年有一闰年，共1461天
	tmp = year & 0x03;
	t_da += (tmp * 365);		//算年
	
	//if((year == 0) && (month < 3))	//2000年1、2月总天数要减1，  //chinge Vx.xxA    
	if(((year % 4) == 0) && (month < 3))	//2000年1、2月总天数要减1，
		t_da += (day - 1);	//而其它的在下面算天数时由于闰年29天，在monthdat[2]数组中只算了28天，所以不用减1	
	else 
		t_da += day;		//算天
	for(tmp = 1; tmp < month; tmp++)	//算月
		t_da += monthday[tmp-1];	//由于闰年29天，在monthdat[2]数组中只算了28天，所以不用减1
	date = t_da;		//上传的天数=实际天数-1  （2000年01月01日 数值为0）
	t_ti = hour * 1800 + minute * 30 + second / 2;
	time = t_ti;
}