AVR单片机程序——电脑键盘（P/S2口协议）——pckey

#include #include #include #include #include#include "scancodes.h"#include "74c922.h" #define GETPSDATA() ((PIND>>PIND7)&0x1)     //connect to PD7#define GETPSCLK() ((PIND>>PIND2)&0x1) //connetc to PD2static unsigned char IntNum = 0; //count the interruptstatic unsigned char KeyV; //it is the key Valuestatic unsigned char DisNum = 1; //显示用指针static unsigned char Key_UP=0;//Key_UP means release the key, Shift = 0static unsigned char BF = 0; //标识是否有字符被收到 
SIGNAL(SIG_INTERRUPT0){ if ((IntNum > 0) && (IntNum < 9))  {             KeyV = KeyV >> 1; //因键盘数据是低>>高，结合上一句所以右移一位   if (GETPSDATA()) KeyV = KeyV | 0x80; //当键盘数据线为1时为1到最高位  } IntNum++; while (!GETPSCLK()); //等待PS/2CLK拉高 if (IntNum > 10)  {   IntNum = 0; //当中断11次后表示一帧数据收完，清变量准备下一次接收   BF = 1; //标识有字符输入完了   cli(); //关中断等显示完后再开中断 (注：如这里不用BF和关中断直接调Decode()则所Decode中所调用的所有函数要声明为再入函数)  }}void Decode(unsigned char ScanCode) //注意:如SHIFT+G为12H 34H F0H 34H F0H 12H，也就是说shift的通码+G的通码+shift的断码+G的断码{ unsigned char TempCyc;  if (!Key_UP)                //当键盘松开时  {   switch (ScanCode) {    case 0xF0 :Key_UP = 1;break;// 当收到0xF0，Key_UP置1表示断码开始    default:     if (DisNum > 16)         {         DisNum = 1;      Clear_Screen();      }           for (TempCyc = 0;(UnShifted[TempCyc][0]!=ScanCode)&&(TempCyc<60); TempCyc++); //查表显示      if (UnShifted[TempCyc][0] == ScanCode)       {       Write_Position(2,DisNum);       Write_Data(UnShifted[TempCyc][1]);       }      DisNum++;           break;   }  } else  {    Key_UP = 0;  } BF = 0; //标识字符处理完了}int main(void){ DDRD=0x70; PORTD=0x00; Initialize_LCD(); Write_Position(1,1); Write_String("hello"); GICR=(1<  MCUCR=(1<  sei();//start the interrupt do  {   if (BF)    Decode(KeyV);   else    sei(); //开中断  } while(1);}  "scancodes.h"unsigned char/* code*/ UnShifted[59][2] = {0x1C, 'a',0x32, 'b',0x21, 'c',0x23, 'd',0x24, 'e',0x2B, 'f',0x34, 'g',0x33, 'h',0x43, 'i',0x3B, 'j',0x42, 'k',0x4B, 'l',0x3A, 'm',0x31, 'n',0x44, 'o',0x4D, 'p',0x15, 'q',0x2D, 'r',0x1B, 's',0x2C, 't',0x3C, 'u',0x2A, 'v',0x1D, 'w',0x22, 'x',0x35, 'y',0x1A, 'z',0x45, '0',0x16, '1',0x1E, '2',0x26, '3',0x25, '4',0x2E, '5',0x36, '6',0x3D, '7',0x3E, '8',0x46, '9',0x0E, '`',0x4E, '-',0x55, '=',0x5D, '',0x29, ' ',0x54, '[',0x5B, ']',0x4C, ';',0x52, ''',0x41, ',',0x49, '.',0x4A, '/',0x71, '.',0x70, '0',0x69, '1',0x72, '2',0x7A, '3',0x6B, '4',0x73, '5',0x74, '6',0x6C, '7',0x75, '8',0x7D, '9',};unsigned char/* code*/ Shifted[59][2] = {0x1C, 'A',0x32, 'B',0x21, 'C',0x23, 'D',0x24, 'E',0x2B, 'F',0x34, 'G',0x33, 'H',0x43, 'I',0x3B, 'J',0x42, 'K',0x4B, 'L',0x3A, 'M',0x31, 'N',0x44, 'O',0x4D, 'P',0x15, 'Q',0x2D, 'R',0x1B, 'S',0x2C, 'T',0x3C, 'U',0x2A, 'V',0x1D, 'W',0x22, 'X',0x35, 'Y',0x1A, 'Z',0x45, '0',0x16, '1',0x1E, '2',0x26, '3',0x25, '4',0x2E, '5',0x36, '6',0x3D, '7',0x3E, '8',0x46, '9',0x0E, '~',0x4E, '_',0x55, '+',0x5D, '|',0x29, ' ',0x54, '{',0x5B, '}',0x4C, ':',0x52, '"',0x41, '<',0x49, '>',0x4A, '?',0x71, '.',0x70, '0',0x69, '1',0x72, '2',0x7A, '3',0x6B, '4',0x73, '5',0x74, '6',0x6C, '7',0x75, '8',0x7D, '9',};