DIY - PIC： PIC18F4550 PS/2 鍵盤中斷程式 (一百二十七)

DIY - PIC： PIC18F4550 PS/2 鍵盤中斷程式 (一百二十七)：

PS/2 鍵盤 Data Line 接上 RB3 和 Clock Line 接上 RB2，這次使用了 18F4550 的 PORTB RB2 作為按鍵中斷 I/O，每當鍵盤由 High 變成 Low，便會觸發中斷，執行程式，而程式是會接收 RB3的數據時，會暫時停止 RB2 的中斷服務，直至將 Data 的數據全部接收，並將數據全部顯示在 LCD 屏上。

  ▲ PIC18F4550鍵盤中斷程式流程圖

▼主程式

void main(void) {     // Set up RB2 Interrupt     INTCON2bits.RBPU = 0;       // Enable Pull up resistors at PORTB     INTCON2bits.INTEDG2 = 0;    // Ext INT2 1=Rising Edge,0=Falling Edge                 LATBbits.LATB2 = 1;             // Latch 1 to RB2     LATBbits.LATB3 = 1;             // Latch 0 to RB3     PS2KeyInit();               // Init PS2 Parameters     // Set up RB2 Interrupt     RCONbits.IPEN      = 1;     // Enable INT Priority     INTCON3bits.INT2IP = 1;     // Set RB2 High INT2 1=High,0=Low     INTCON3bits.INT2IE = 1;     // Enable RB2 INT2 1=Enable,0=Disable     INTCONbits.PEIE    = 1;     // Enable Peripheral INT     INTCONbits.GIE     = 1;     // Enable Global INT     // Check the PS2 Keyboard BAT After RST~320ms Max=500ms         for (timeout=0;timeout<50;timeout++){                 Delay10KTCYx(5);        // 10,000x(4 x 0.05us)=2ms*5=10ms                 if(PS2KeyHit()){                         itoa(timeout,disp_temp);                         putsXLCD(disp_temp);                         putrsXLCD(" ");                                               PS2Key_Char = PS2KeyGetKey();                         timeout=254;                         }                      }     // Check the PS2 Keyboard BAT 0xAA/0xFC Code                 if (PS2Key_Char == 0xAA){                         itoa(PS2Key_Char,disp_temp);                         putsXLCD(disp_temp);                         putrsXLCD(" READY");                 } else putrsXLCD(" ERROR"); while(1) { timeout++;                 if(timeout>150){                                 timeout=0;                                 LcdSetLine2();                                 putrsXLCD("                ");                                 LcdSetLine2();                 }                 if(PS2KeyHit()){                     PS2Key_Char = PS2KeyGetKey();                 temp=(PS2Key_Char & 0xF0);                 temp=(temp>>4)+48;                 if (temp>57) temp=temp+7;                 disp_temp[0]=temp;disp_temp[1]='\0';                 putsXLCD(disp_temp);                 temp=(PS2Key_Char & 0x0F)+48;                         if (temp>57) temp=temp+7;                 disp_temp[0]=temp;disp_temp[1]='\0';                             putsXLCD(disp_temp);                 putrsXLCD("");                 }                 LATAbits.LATA0 = 0;                     // RA0=0 LED=OFF Scope=50ms                 Delay10KTCYx(10);                     // 10,000 x 1 x (4 x 0.05us) = 2ms                                                                         LATAbits.LATA0 = 1;                     // RA0=1 LED=ON Scope=1                 Delay10KTCYx(10);                     // 10,000 x 1 x (4 x 0.05us) = 2ms                                                            // Scope = 2ms }         } // Main End

▼中斷副程式

void low_isr() {     INTCON3bits.INT2IE = 0;     // Disable RB2 INT Flag     INTCON3bits.INT2IF = 0;     // Clear RB2 INT Flag     PS2KeyIntHandler();         // PS2 Key INT Handler     INTCON3bits.INT2IE = 1;     // Enable RB2 INT2 1=Enable,0=Disable     INTCONbits.GIE     = 1;     // Enable All INT }

▲ PS/2 鍵盤接上控制板

▲ 鍵盤執行 BAT，完成後，數據 0xAA = 170

 測試 BWS 按鍵：

  ▲ 按 B鍵數據 32 F0 32

▲ 按 W鍵數據 1D F0 1D

▲ 按 S鍵數據 1B F0 1B