主要器件：

1、  AT89C52单片机芯片，用于控制充电器芯片。

2、  可提供精确的恒流/恒压充电，可对所有化学类型的Li+电池进行安全充电的MAX1898。

3、  LM7805提供稳定的+5v电压。

试验程序代码：
//BattCharger.h程序

#ifndef       _BATTCHARGER_H                            // 防止BattCharger.h被重复引用

#define       _BATTCHARGER_H

#include

#define uchar unsigned char

#define uint unsigned int

sbit GATE = P2^0;

sbit BP = P2^1;

uint t_count,int0_count;

#endif

//BattCharger.c程序

#include "BattCharger.h"

/* 定时器0中断服务子程序 */

void timer0() interrupt 1 using 1

{

       TR0 = 0;                      // 停止计数

       TH0 = -5000/256;             // 重设计数初值

       TL0 = -5000%256;

       t_count++;      

       if (t_count>600)        // 第一次外部中断0产生后3s

       {

              if (int0_count==1)       // 还没有出现第二次外部中断0，则认为充电完毕

              {

                     GATE = 0;              // 关闭充电电源

                     BP = 0;                  // 打开蜂鸣器报警

              }

           else                       // 否则即是充电出错

              {

                     GATE = 1;      

                     BP = 1;          

              }

              ET0 = 0;                     // 关闭T0中断

              EX0 = 0;                  // 关闭外部中断0

              int0_count = 0;

              t_count = 0;

       }

       else

              TR0 = 1;                  // 启动T0计数

}

/* 外部中断0服务子程序 */

void int0() interrupt 0 using 1

{

       if (int0_count==0)

       {

              TH0 = -5000/256;      // 5ms定时

              TL0 = -5000%256;   

              TR0 = 1;                  // 启动定时/计数器0计数

              t_count = 0;              // 产生定时器0中断的计数器清零

       }

       int0_count++;

}

/* 初始化 */

void init()

{

       EA = 1;                        // 打开CPU中断

       PT0 = 1;               // T0中断设为高优先级

       TMOD = 0x01;             // 模式1，T0为16位定时/计数器

       ET0 = 1;               // 打开T0中断

       IT0 = 1;                // 外部中断0设为边沿触发

       EX0 = 1;               // 打开外部中断0

       GATE = 1;                  // 光耦正常输出电压

       BP = 1;                         // 关闭蜂鸣器

       int0_count = 0;        // 产生外部中断0的计数器清零

}

void main()

{

       /* 调用初始化函数 */

       init();

       /* 无限循环 */

       while(1);

}