main.c

周立功单片机上的源程序

/*
	main.c
	CAT1021 EEPROM读写实验
*/


#include "I2C.h"
#include <reg51.h>
#include <string.h>
#include <stdlib.h>


//定义I/O端口
sbit SCL = P3^4;
sbit SDA = P3^5;


/*
函数：Delay()
功能：延时0.001～65.536s
参数：
	t>0时，延时(t*0.001)s
	t=0时，延时65.536s
*/
void Delay(unsigned int t)
{
	do
	{
		TH0 = 0xFC;
		TL0 = 0x66+17;
		TR0 = 1;
		while ( !TF0 );
		TR0 = 0;
		TF0 = 0;
	} while ( --t != 0 );
}


/*
函数：Feed()
功能：清除CAT1021内部WDT定时器（喂狗）
说明：如果没有在1.6秒（典型值）内喂狗，则CAT1021会输出复位信号
*/
void Feed()
{
	unsigned char t = 10;
	I2C_SDA = 0;
	while ( --t != 0 );
	I2C_SDA = 1;
}


/*
函数：UartInit()
功能：串行口初始化
*/
void UartInit()
{
	RXD = 1;
	TXD = 1;
	SCON = 0x50;	//串口方式1（8位Uart），允许接收
	PCON |= 0x80;	//波特率加倍
	TMOD &= 0x0F;
	TMOD |= 0x20;	//T1设置为8位自动重装定时器
	TH1 = TL1 = 0xFA;	//设置波特率为9600
	TR1 = 1;
}


/*
函数：PutChar()
功能：从串行口输出字符c
*/
void PutChar(char c)
{
	SBUF = c;
	while ( !TI ) Feed();
	TI = 0;
}


/*
函数：PutStr()
功能：从串行口输出字符串*s
*/
void PutStr(char *s)
{
	unsigned char c;
	for (;;)
	{
		c = *s++;
		if ( c == '\0' ) break;
		PutChar(c);
	}
}


/*
函数：GetStr()
功能：从串行口接收一个字符串
参数：
	*s：返回输入的字符串
	n：最大长度限制
说明：输入的字符串以回车键结束
*/
void GetStr(char *s, unsigned char n)
{
	unsigned char c;
	for (;;)
	{
		while ( !RI ) Feed();
		c = SBUF;
		RI = 0;
		if ( c == '\n' ) break;
		if ( c == '\0' ) break;
		if ( (n != 0) && (c >= ' ') )
		{
			*s++ = c;
			n--;
		}
	}
	*s = '\0';
}


/*
函数：SysInit()
功能：系统初始化
*/
void SysInit()
{
	unsigned char c;
	I2C_Init();
	TMOD &= 0xF0;
	TMOD |= 0x01;
	UartInit();
	Delay(300);		//上电后必须先延时200ms以上才能对CAT1021进行操作
	if ( I2C_Get(0xA0,0,&c) )
	{
		PutStr("\r\nCAT1021 not found!");
		for (;;)
		{
			Feed();
			Delay(800);
		}
	}
}


/*
函数：BytetoHex()
功能：字节c转换成16进制字符串
*/
void ByteToHex(char *s, unsigned char c)
{
	code unsigned char Tab[] = "0123456789ABCDEF";
	*s++ = Tab[c / 16];
	*s++ = Tab[c & 0x0F];
	*s = '\0';
}


/*
函数：Read()
功能：读取CAT1021内部EEPROM的数据
参数：
	addr：起始地址，取值0～255
	len：读取的数据长度，取值1～256
*/
void Read(unsigned char addr, unsigned char len)
{
	unsigned char c;
	unsigned char s[3];
	PutStr("addr data ASCII\r\n");
	do
	{
		ByteToHex(s,addr);
		PutStr(s);
		PutStr("   ");
		I2C_Get(0xA0,addr++,&c);
		ByteToHex(s,c);
		PutStr(s);
		if ( (c > ' ') && ( c != 0xFF ) )
		{
			PutStr("   ");
			PutChar(c);
		}
		PutStr("\r\n");
	} while ( --len != 0 );
}


/*
函数：Write()
功能：向CAT1021内部的EEPROM写入一个字符串
参数：
	addr：起始地址，取值0～255
	*s：输入的字符串
*/
void Write(unsigned char addr, char *s)
{
	unsigned char c;
	for (;;)
	{
		c = *s++;
		I2C_Put(0xA0,addr++,c);
		Delay(5);
		if ( c == '\0' ) break;
	}
}


/*
函数：Input()
功能：从串行口输入一个字符串
参数：
	*s1：输入前显示的提示语
	*s2：保存输入的字符串
	len：最大长度限制
*/
void Input(char *s1, char *s2, unsigned char len)
{
	PutStr(s1);
	GetStr(s2,len);
	PutStr(s2);
	PutStr("\r\n");
}


void main()
{
	unsigned char addr;
	unsigned char len;
	char s[41];
	SysInit();
	for (;;)
	{
		PutStr("\r\n");
		Input("cmd>",s,40);
		if ( !strcmp(s,"read") )
		{
			Input("address = ",s,40);
			addr = atoi(s);
			Input("length = ",s,40);
			len = atoi(s);
			Read(addr,len);
		}
		else if ( !strcmp(s,"write") )
		{
			Input("address = ",s,40);
			addr = atoi(s);
			Input("string = ",s,40);
			Write(addr,s);
		}
		else
		{
			PutStr("error!");
		}
	}
}