14.c

C51实用程序（45个） I/O、定时器、中断、看门狗、计数器、软件AD、VB串口、93c06驱动、24c02系列驱动、7219、20045、软件陷阱、串口中断、码值转换、AVR通讯、IIC、D

#include <reg52.h>
#include <intrins.h>

unsigned char time,b_break,b_break_3;
//35.555ms
void int_t0(void) interrupt 1 
{
	TH0=0;
	if ((++b_break_3)>2) b_break=1;
	time++;
}

void wait20us(void) 
{
	TL0=210;TH0=0xff;
	time=0;
	while (!time) {}
}
void wait35ms(void) 
{
	TH0=0;time=0;
	while (!time) {}
}
void wait1s(void) 
{
	time=0;
	while (time<30) {}
}

unsigned char rec(void) 
{
	TH0=0;b_break_3=0;b_break=0;
	while (RI==0) 
{
		if (b_break) return(1);
	}
	RI=0;
	SBUF=SBUF;
	return(SBUF);
}

//返回1表示失败
bit sen(unsigned char d) 
{
	SBUF=d;
	TH0=0;b_break_3=0;b_break=0;
	while (RI==0) 
{
		if (b_break) return(1);
	}
	RI=0;
	if (SBUF!=d) return(1);
	return(0);
}

#define b_init 0

#define b_erase 1
#define b_erase_block 2				//P89C51RC+、P89C51RD+特有
#define b_erase_sbyte_bvec 3		//P89C51RC+、P89C51RD+特有

#define b_read 4

#define b_program_byte 5
#define b_program_sbyte 6			//P89C51RC+、P89C51RD+特有
#define b_program_boot_vector 7		//P89C51RC+、P89C51RD+特有

#define b_lock1 8
#define b_lock12 9
#define b_lock123 10

#define b_cpu 12					//定义需要编程的cpu类型,0:P89C51 1:P89C52 2:P89C54 3:P89C58 4:P89C51RC+ 5:P89C51RD+

sbit p_oe=P3^2;
sbit p_we=P3^3;
//输入控制模式
void mode(unsigned char m) 
{
	P3=(m<<4)|0xf;
}
void out_adds(unsigned int adds) 
{
	P0=adds;
	P2=adds/256;
}
unsigned char in_data(void) 
{
	P1=0xff;
	p_oe=0;
	return(P1);
	p_oe=1;
}

//判别cpu类型
unsigned char code un_cpu[]={0xf4,0xff,0xfb,0xf9,0x89,0x80};
unsigned char read_id(void)
{
	unsigned char d;
	mode(0xf);
	                                     //读Mft ID
	out_adds(0);d=in_data();
	if (d!=0x15) return(0);
	                                     //读Mft ID1
	out_adds(1);d=in_data();
	if (d!=0xc2) return(0);
	                                     //读Mft ID2
	out_adds(2);d=in_data();
	return(d);		                     //返回Mft ID2
}

//芯片初始化
bit init(void) 
{
	unsigned char b_error=0,time_calc;
	mode(0xe);
	wait35ms();			                //防止电脑处理不过来

	p_we=0;
	time=0;		                        //等待0.5秒
	time_calc=time;
	while (1) 
{
		while (time==time_calc) {}
		time_calc=time;
		if (sen(0xf)) return(1);	    //发送"正在初始化"标志：0xf
		if (time>15) break;
	}
	wait35ms();                         //test
	p_we=1;
	                                    //抽样检查擦除是否成功
	mode(0x4);
	out_adds(0);if (in_data()!=0xff) b_error=1;
	out_adds(1);if (in_data()!=0xff) b_error=1;
	out_adds(0xff);if (in_data()!=0xff) b_error=1;
	out_adds(0xfff);if (in_data()!=0xff) b_error=1;
	out_adds(0x1fff);if (in_data()!=0xff) b_error=1;
	sen(b_error);						//跟据b_error发送
	return(b_error);
}

bit program_byte(void) 
{
	unsigned char d,n;
	unsigned int adds;
	do 
{
		d=rec();
		if (!b_break) 
{
			out_adds(adds);
			P1=d;
			n=0;
			while (1) 
{
			mode(0x3);
			p_we=0;
			wait20us();
			p_we=1;
			mode(0x5);
			if (in_data()!=d) n++; else break;
			if (n>2) return(1);				//编程校验3次失败
			}
			adds++;
		} 
else return(0);                       //pc通信超时或编程完成。在此不会区
//分，但无所谓
	}
 while (adds);
	return(1);								//地址超过64k
}

bit lock123(void) 
{
	unsigned char i,b_error=0;
	unsigned int adds;
	wait20us();
	for (i=0;i<3;i++) 
{ 
		mode(0x6);
		out_adds(i);
		p_we=0;
		wait20us();
		p_we=1;
	}
	                                         //检查前4kb是否加密成功(为了节省
//时间，只检查前4kb)
	mode(0x0);
	for (adds=0;adds<4096;adds++) 
{
		out_adds(adds);
		if (in_data()!=0xff) {b_error=1;break;}
	}
	sen(b_error);
	return(b_error);							
}

void main(void) 
{
	unsigned char cpu;
	unsigned char i,start;
	EA=1;
	SCON=0xd8;PCON=0x80;
	TMOD=0x21;
	TL1=TH1=0xff;TR1=1;
	TH0=0;ET0=TR0=1;
	while (1) 
{
		REN=1;
		start=rec();
		if ((!b_break)&&(start==0x0)) 
{
			i=rec();
			if (!b_break) 
{
				switch (i) 
{
				case b_cpu:
				i=rec();
				if (!b_break) cpu=i;
				wait35ms();			         //防止电脑处理不过来
				if (un_cpu[i]!=read_id()) sen(1); else sen(0);
				break;
				case b_init:
					if (init()) wait1s();   //初始化错误或通信错误等待1秒，让
//pc程序超时并报告错误
					break;
				case b_program_byte:
		if (program_byte()) wait1s();	//编程错误或通信错误等待1秒，让pc程序
//超时并报告错误
					break;
				case b_lock123:
		if (lock123()) wait1s();		//加密错误或通信错误等待1秒，让pc程序
//超时并报告错误
					break;
				}
			}
		}
	}
}