单片机与键盘接口程序

单片机与键盘接口程序

void int1proc() interrupt IE1_VECTOR using 1
{
unsigned char i, key;
code unsigned char PS2TAB[] = {//20键PS2小键盘键码表
  0x70,//0
  0x69,//1
  0x72,//2
  0x7a,//3
  0x6b,//4
  0x73,//5
  0x74,//6
  0x6c,//7
  0x75,//8
  0x7d,//9
  0x05,//F1
  0x06,//F2
  0x04,//F3
  0x0c,//F4
  0x03,//F5
  0x0b,//F6
  0x5a,//Enter
  0x76,//Esc
  0x66,//Bksp
  0x71//KP.
  };
  if (PS2Buffers.PS2KeyCount == 0){//PS2起始位测试
    if (!PS2CLOCK && !PS2DATA){//低电平是起始位
      if (PS2Buffers.PS2KeyExtFlage != 0xf0){
        PS2Buffers.PS2KeyTemp = 0;
        PS2Buffers.PS2KeyExtFlage = 0;
        PS2Buffers.PS2KeyPopError = 0;
      }
      PS2Buffers.PS2KeyCount ++;//脉冲计数
    }
    else PS2Buffers.PS2KeyPopError = 0xeb;//置键起始位错误号0xeb
  }
  else if (PS2Buffers.PS2KeyCount < 9){//PS2数据位
    key = PS2Buffers.PS2KeyTemp;//取键盘缓冲区移位数据
    key >>= 1;
    if (PS2DATA) key = 0x80;
    PS2Buffers.PS2KeyTemp = key;
    PS2Buffers.PS2KeyCount++;//脉冲计数
  }
  else if (PS2Buffers.PS2KeyCount == 9){//PS2数据奇校验
    ACC = PS2Buffers.PS2KeyTemp;//取键盘缓冲区移位数据(C51取偶校验位)
    if (P != PS2DATA) PS2Buffers.PS2KeyCount ++;//脉冲计数
    else{
      PS2Buffers.PS2KeyPopError = 0xec;////置键奇校验位错误号0xec
      PS2Buffers.PS2KeyCount = 0;//脉冲计数归零
    }
  }
  else if (PS2Buffers.PS2KeyCount == 10){//停止位
    key = PS2Buffers.PS2KeyTemp;//取键盘缓冲区移位数据
    PS2Buffers.PS2KeyCount = 0;//脉冲计数归零
    if (PS2DATA){//高电平是停止位
      if (key == 0xe0){//本次是扩展键
        PS2Buffers.PS2KeyExtFlage = 0xe0;//置扩展键标志(小键盘只有回车键)
      }
      else if (key == 0xf0){//本次是键断码,键释放
        PS2Buffers.PS2KeyExtFlage = 0xf0;//置键释放标志
      }
      else{//本次必为键值
        if ((key == 0xaa) (key == 0xfa)) PS2Buffers.PS2KeyPushCount = 0;//长
压键计数器清零
        else{
            PS2CLOCK = 0;//阻止PS2键盘立即回送数据
          PS2Buffers.PS2KeyPopError = 0xaa;//出错码
          for (i = 0; i < 20; i++){
            if (key == (PS2TAB[i])){//搜索
              key = i + 1;
              if (PS2Buffers.PS2KeyExtFlage == 0xf0){
                key = 0x80;//键释放
                PS2Buffers.PS2KeyPushCount = 0;//长压键计数器清零
                PS2Buffers.PS2KeyMessage = key;//存入当前键值并执行命令
              }
              else{
                if (key != PS2Buffers.PS2KeyVal){//换了一个键
                  PS2Buffers.PS2KeyPushCount = 0;//长压键计数器清零
                  PS2Buffers.PS2KeyMessage = key;//存入当前键值并执行命令
                }
                else{//未换键
                  PS2Buffers.PS2KeyPushCount ++;//长压键计数器计数
                  if (PS2Buffers.PS2KeyPushCount > DEFPS2PUSHCOUNT){//长压时间到
                    PS2Buffers.PS2KeyMessage = key 0x40;//存入当前键值并执行命
令
                    PS2Buffers.PS2KeyPushCount = 0;//长压键计数器清零
                  }
                }
              }
              PS2Buffers.PS2KeyVal = key;//存入当前键值值1~20或0x80+(1~20)
              PS2Buffers.PS2KeyTemp = 0;//键码移位记录器
              PS2Buffers.PS2KeyExtFlage = 0;//扩展键标志
              PS2Buffers.PS2KeyPopError = 0;//键释放标志或出错码
              break;
            }
          }
          if (PS2Buffers.PS2KeyPopError) PS2Buffers.PS2KeyPushCount = 0;//长压键
计数器清零
          PS2CLOCK = 1;//释放PS2时钟总线
        }
      }
    }
    else PS2Buffers.PS2KeyPopError = 0xed;//置停止位错误号0xed
  }
  else PS2Buffers.PS2KeyCount = 0;//PS2键盘出错
}
/*------------------------------------------------------------------
         利用函数指针数组运行PS2键盘散转命令
-------------------------------------------------------------------*/
void PS2CommandExec(unsigned char key)
{
unsigned int i;
code void *funcpushbuffers[] = {//命令散转表(汇编中的16个DW)
/*------------------------------------------------------------------
         15个压键、放键及长压键事件处理函数指针地址
-------------------------------------------------------------------*/
  (void *)ClrWdt            + 0x0000,
/*---------------------------------------------
           10个功能键压键事件处理(独立管理)
----------------------------------------------*/
  (void *)PS2F1KeyPush      + 0x5b7d,      //功能键F1压键事件处理
  (void *)PS2F2KeyPush      + 0xa6ea,      //功能键F2压键事件处理
  (void *)PS2F3KeyPush      + 0xf157,      //功能键F3压键事件处理
  (void *)PS2F4KeyPush      + 0x4cc4,      //功能键F4压键事件处理
  (void *)PS2F5KeyPush      + 0x9731,      //功能键F5压键事件处理
  (void *)PS2F6KeyPush      + 0xe2ae,      //功能键F6压键事件处理
  (void *)PS2EnterKeyPush   + 0x3d1b,      //功能键Enter压键事件处理
  (void *)PS2EscKeyPush     + 0x8888,      //功能键Esc压键事件处理
  (void *)PS2BkspKeyPush    + 0xd3f5,      //功能键Bksp压键事件处理
  (void *)PS2KpKeyPush      + 0x2e62,      //功能键Kp压键事件处理
/*---------------------------------------------
           2个放键事件处理(集中管理)
----------------------------------------------*/
  (void *)PS2NumberKeyPop   + 0x79df,      //数字键放键事件处理
  (void *)PS2FuncKeyPop     + 0xc44c,      //功能键放键事件处理
/*---------------------------------------------
           2个长压键事件处理(集中管理)
----------------------------------------------*/
  (void *)PS2NumberKeyPushL + 0x1fb9,      //数字键长压键事件处理
  (void *)PS2FuncKeyPushL   + 0x6a26,      //功能键长压键事件处理
/*---------------------------------------------
           1个数字键压键事件处理(集中管理)
----------------------------------------------*/
  (void *)PS2NumberKeyPush  + 0xb593       //数字键0~9压键事件处理
  };
/*--------------------------------------------*/
  i = key;
  key &= 0x3f;//去掉键释放及长压键标志,取真键码
  key --;
  if (key < 20){//只有20个键
    if (key < 10){//数字键0~9
      if (i <= 10) key = 15;//(散转号0)压数字键0~9
      else{
        if (i & 0x80) key = 11;//(散转号11)放数字键0~9
        else key = 13;//(散转号13)长压数字键0~9
      }
    }
    else{//压功能键F1~F6,Enter..KP
      if ((i & 0xc0) == 0) key -= 9;//(散转号1~10)压功能键F1~F6,Enter..KP
      else{
        if (i & 0x80) key = 12;//(散转号12)放功能键
        else key = 14;//(散转号14)长压功能键
      }
    }
    ClrWdt();//喂狗(鬼知道键盘程序要运行多久,就替它先喂一次吧)
    i = ((key * 53 & 0xf) * 0x1000)+ ((key * 43 & 0xf) * 0x100) + ((key * 23 &
0xf) * 0x10) + (key * 13 & 0xf);
    _icall_((void *)funcpushbuffers[key] - i);//取键盘散转表并执行键盘命令
  }
}
这个程序与一般网上的有很大区别,它充分利用了外部中断(0字)hotpower[1次]