设计要求
使用E2PROM完成数据记录功能，单片机复位次数记录到E2PROM的地址0中。每复位一次数值加1，按下按键S4，串口发送复位次数。串口发送格式如下：
Number：1
备注：
单片机IRC振荡器频率设置为12MHz。
按键模式：BTN；扩展方式：IO模式。
串口通信波特率设置为 9600。
代码：
sys.h
#ifndef __SYS_H__
#define __SYS_H__
#include <STC15F2K60S2.H>
#include "intrins.h"
sbit scl=P2^0;
sbit sda=P2^1;
extern bit flag_send;//用于标明是否发送数据
extern bit flag_set;//用于标明是否重置数据（非题意）
void init74hc138(unsigned char n);
void init();
void w_eeprom(unsigned char addr,unsigned char date);
unsigned char r_eeprom(unsigned char addr);
void Key_Loop();
#endifmain.c
#include "sys.h"
unsigned char eeprom_count=0;//EEPROM中的计数值
unsigned char *str = "Number: ";
bit flag_key=0;
void UartInit(void) //9600bps@12.000MHz
{
SCON = 0x50; //8位数据,可变波特率
AUXR |= 0x40; //定时器时钟1T模式
AUXR &= 0xFE; //串口1选择定时器1为波特率发生器
TMOD &= 0x0F; //设置定时器模式
TL1 = 0xC7; //设置定时初始值
TH1 = 0xFE; //设置定时初始值
ET1 = 0; //禁止定时器中断
TR1 = 1; //定时器1开始计时
ES=1;
EA=1;
}
//发送一个字节数据到串口
void send_uart_date(unsigned char date){
SBUF=date;
while(TI==0);
TI=0;
}
//发送字符串到串口
void send_uart_str(unsigned char *str){
while(*str!='\0'){
send_uart_date(*str++);
}
}
//将数字转换为字符串
void num_transt_str(unsigned char num){
if(num>=100)send_uart_date(num/100+'0');
if(num>=10)send_uart_date((num%100)/10+'0');
send_uart_date(num%10+'0');
}
void Timer0_Init(void) //100微秒@12.000MHz
{
AUXR |= 0x80; //定时器时钟1T模式
TMOD &= 0xF0; //设置定时器模式
TL0 = 0x50; //设置定时初始值
TH0 = 0xFB; //设置定时初始值
TF0 = 0; //清除TF0标志
TR0 = 1; //定时器0开始计时
ET0 = 1; //使能定时器0中断
EA=1;
}
void main(){
init();
eeprom_count=r_eeprom(0x00);
eeprom_count++;
w_eeprom(0x00,eeprom_count);
UartInit();
Timer0_Init();
while(1){
if(flag_key){
flag_key=0;
Key_Loop();
}
if(flag_send){
flag_send=0;
send_uart_str(str);//发送Number:
num_transt_str(eeprom_count);//发送计数器数值
send_uart_str("\r\n");//换行
}
if(flag_set){//重置
flag_set=0;
eeprom_count=0;
w_eeprom(0x00,eeprom_count);
}
}
}
void uart() interrupt 4
{
if(RI){
RI=0;
}
}
void Timer0_Isr(void) interrupt 1
{
static unsigned char count=0;
count++;
if(count==50){
count=0;
flag_key=1;
}
}sys.c
#include "sys.h"
unsigned char keyval,keyold,keydown,keyup;
bit flag_send=0;
bit flag_set=0;
void init74hc138(unsigned char n){
P2=(P2&0x1f)|(n<<5);
P2&=0x1f;
}
void init(){
P0=0x00;
init74hc138(5);
P0=0xff;
init74hc138(4);
}
void Key_Loop(){
keyval=0;
if(P33==0)keyval=1;
if(P32==0)keyval=2;
keydown=keyval&(keyold^keyval);
keyup=~keyval&(keyold^keyval);
if(keyval==1&&keyold!=keyval)flag_send=1;
if(keyval==2&&keyold!=keyval)flag_set=1;
keyold=keyval;
}iic.c
#include "sys.h"
#define DELAY_TIME 5
static void I2C_Delay(unsigned char n)
{
do
{
_nop_();_nop_();_nop_();_nop_();_nop_();
_nop_();_nop_();_nop_();_nop_();_nop_();
_nop_();_nop_();_nop_();_nop_();_nop_();
}
while(n--);
}
void I2CStart(void)
{
sda = 1;
scl = 1;
I2C_Delay(DELAY_TIME);
sda = 0;
I2C_Delay(DELAY_TIME);
scl = 0;
}
void I2CStop(void)
{
sda = 0;
scl = 1;
I2C_Delay(DELAY_TIME);
sda = 1;
I2C_Delay(DELAY_TIME);
}
void I2CSendByte(unsigned char byt)
{
unsigned char i;
for(i=0; i<8; i++){
scl = 0;
I2C_Delay(DELAY_TIME);
if(byt & 0x80){
sda = 1;
}
else{
sda = 0;
}
I2C_Delay(DELAY_TIME);
scl = 1;
byt <<= 1;
I2C_Delay(DELAY_TIME);
}
scl = 0;
}
unsigned char I2CReceiveByte(void)
{
unsigned char da;
unsigned char i;
for(i=0;i<8;i++){
scl = 1;
I2C_Delay(DELAY_TIME);
da <<= 1;
if(sda)
da |= 0x01;
scl = 0;
I2C_Delay(DELAY_TIME);
}
return da;
}
unsigned char I2CWaitAck(void)
{
unsigned char ackbit;
scl = 1;
I2C_Delay(DELAY_TIME);
ackbit = sda;
scl = 0;
I2C_Delay(DELAY_TIME);
return ackbit;
}
void I2CSendAck(unsigned char ackbit)
{
scl = 0;
sda = ackbit;
I2C_Delay(DELAY_TIME);
scl = 1;
I2C_Delay(DELAY_TIME);
scl = 0;
sda = 1;
I2C_Delay(DELAY_TIME);
}
//向EEPROM中写入一个字节数据
void w_eeprom(unsigned char addr,unsigned char date){
I2CStart();
I2CSendByte(0xa0);
I2CWaitAck();
I2CSendByte(addr);
I2CWaitAck();
I2CSendByte(date);
I2CWaitAck();
I2CStop();
}
//从EEPROM中读取一个字节数据
unsigned char r_eeprom(unsigned char addr){
unsigned char temp;
I2CStart();
I2CSendByte(0xa0);
I2CWaitAck();
I2CSendByte(addr);
I2CWaitAck();
I2CStart();
I2CSendByte(0xa1);
I2CWaitAck();
temp=I2CReceiveByte();
I2CSendAck(1);
I2CStop();
return temp;
}测试结果
