微處理器 - Microchip PIC12F1822 - Assembly - Interrupt On Change(IOC)

1. 設定TRISA輸入
2. 設定WPUA提昇電阻
3. 設定IOCAx正緣、負緣觸發
4. 開啟GPE、IOC中斷
5. 進入中斷後，清除IOC以及IOCA旗標





main.s

    list p=12f1822, r=hex
    #include <p12f1822.inc>
    __config _CONFIG1, _FOSC_INTOSC & _WDTE_OFF & _MCLRE_OFF
    __config _CONFIG2, _LVP_OFF

    #define tmp 0x20

    org 0x0000
    goto start

    org 0x0004
    goto myisr
   
    org 0x0100
myisr:
    banksel INTCON
    bcf INTCON, 7
    bcf INTCON, 0

    banksel IOCAF
    movlw 0xff
    xorwf IOCAF, w
    andwf IOCAF, f
 
    banksel tmp
    btfss tmp, 0
    bcf PORTA, 0
    btfsc tmp, 0
    bsf PORTA, 0
    movlw 0xff
    xorwf tmp, f

    banksel INTCON
    bsf INTCON, 7
    retfie

start:
    banksel TRISA
    bcf TRISA, 0
    bsf TRISA, 3

    banksel OPTION_REG
    bcf OPTION_REG, 7

    banksel WPUA
    bsf WPUA, 3

    banksel PORTA
    bsf PORTA, 0

    banksel tmp
    clrf tmp

    banksel IOCAN
    bsf IOCAN, 3

    banksel INTCON
    bsf INTCON, 7
    bsf INTCON, 3
    bcf INTCON, 0

    goto $
    end

編譯

$ gpasm main.s

完成