A: odd B: even C: even

midterm_easy.asm

    port4       EQU 0E8h
    shift7LED   EQU 0FEh
    dispBuf     EQU 40h
    keyBuf1     EQU 44h
    keyBuf2     EQU 45h
    keyCode     EQU 46h
    keyCheck    EQU 47h
    debCounter  EQU 48h
    debTimes    EQU 60
    CLEAR       BIT 05h
    preValue    EQU 50h
    Negative    BIT 02h
    ORG 0000h
    MOV keyCode,#0FFh
    MOV keyCheck,#0FFh
    MOV debCounter,#0
    MOV A, #0FFh
    MOV P2, A
    MOV P3, A
    MOV keyBuf1, #0FFh
    MOV keyBuf2, #0FFh
    MOV dispBuf, #0
    MOV dispBuf+1, #0
    MOV dispBuf+2, #0
    MOV dispBuf+3, #0
    MOV preValue, #0
    MOV preValue+1, #0
    MOV preValue+2, #0
    MOV preValue+3, #0
    SETB CLEAR
    CLR Negative
    SJMP SHOW3
RESET:
    MOV R0, #dispBuf
    MOV A, #shift7LED
    SJMP LOOP
SHOW3:
    MOV R0, #dispBuf+3
    MOV A, #0F7h
LOOP:
    MOV port4, A
    ACALL CHECKNEG
    ACALL COVLED
    ACALL GETKEYCODE
    ACALL DELAYKEYDEBOUNCE
    JB CLEAR, SHOW3
    INC R0
    RL A
    JB ACC.4, LOOP
    SJMP RESET
CHECKNEG:
    PUSH 0E0h
    JNB Negative, EXITCHECKNEG
    MOV P1, #07Fh
    SJMP EXITCHECKNEG2
EXITCHECKNEG:
    MOV P1, #0FFh
EXITCHECKNEG2:
    POP 0E0h
    RET
GETKEYCODE:
    PUSH 0E0h
    MOV A, P2
    MOV keyBuf1, A
    MOV A, p3
    MOV keyBuf2, A
    CJNE A, #0FFh, P3HASINPUT
    MOV A, keyBuf1
    MOV R2, #0
CHECKP2:
    JNB 0E0h, GOTKEYCODE
    INC R2
    RR A
    CJNE R2, #8, CHECKP2
    SJMP EXITGETKEYCODE
P3HASINPUT:
    MOV A, keyBuf2
    MOV R2, #8
P3BIT:
    JNB 0E0h, GOTKEYCODE
    INC R2
    RR A
    CJNE R2, #16, P3BIT
    SJMP EXITGETKEYCODE
GOTKEYCODE:
    MOV keyCode, R2
EXITGETKEYCODE:
    POP 0E0h
    RET
DELAY:
    MOV R4, #1
    DELAY0:MOV R5, #2
    DELAY1:MOV R6, #100
    DELAY2:MOV R7, #100
    DELAY3:DJNZ R7, DELAY3
    DJNZ R6, DELAY2
    DJNZ R5, DELAY1
    DJNZ R4, DELAY0
    RET
COVLED:
    PUSH 0E0h
    MOV A, @R0
    ANL A, #0Fh
    MOV DPTR, #LED_TABLE
    MOVC A, @A+DPTR
    MOV P0, A
    POP 0E0h
    RET
DELAYKEYDEBOUNCE:
    PUSH 0E0h
    ACALL DELAY
    INC debCounter
    MOV R5,debCounter
    CJNE R5,#debTimes,DELAYEXIT
    MOV debCounter,#0
    MOV A,keyCode
    CJNE A,#0FFh,HASINPUT
    SJMP DELAYEXIT
EXIT:
    MOV keyCheck,keyCode
DELAYEXIT:
    POP 0E0h
    RET
HASINPUT:
    MOV A,keyCode
    ANL A, #0Fh
    MOV DPTR, #TRANSFORM
    MOVC A, @A+DPTR
    MOV keyCode, A
    CJNE A,keyCheck,EXIT
    CJNE A,#0Fh, SUBTRACTION
    SETB CLEAR
    CLR Negative
    MOV A, #0
    ACALL SETDIGITS
    SJMP RESET2
SUBTRACTION:
    CJNE A,#0Dh, EQUAL
    SETB CLEAR
    MOV preValue, dispBuf
    MOV preValue+1, dispBuf+1
    MOV preValue+2, dispBuf+2
    MOV preValue+3, dispBuf+3
    MOV dispBuf+3, A
    MOV dispBuf+2, #0
    MOV dispBuf+1, #0
    MOV dispBuf, #0
    SJMP RESET2
ISNUMBER:
    JNB CLEAR, CONTINUE
    CLR CLEAR
    MOV dispBuf+3, #0
CONTINUE:
    ADD A,#246
    JC RESET2
    ACALL DISPLAYKEYPATTERN
RESET2:
    MOV keyCode,#0FFh
    MOV keyCheck,#0FFh
    SJMP DELAYEXIT
EQUAL:
    CJNE A, #0Eh, ISNUMBER
    CLR C
    MOV A, preValue+3
    SUBB A, dispBuf+3
    ACALL DAAA
    MOV preValue+3, A
    MOV dispBuf+3, A
    MOV A, preValue+2
    SUBB A, dispBuf+2
    ACALL DAAA
    MOV preValue+2, A
    MOV dispBuf+2, A
    MOV A, preValue+1
    SUBB A, dispBuf+1
    ACALL DAAA
    MOV preValue+1, A
    MOV dispBuf+1, A
    MOV A, preValue
    SUBB A, dispBuf
    ACALL DAAA
    MOV preValue, A
    MOV dispBuf, A
    JNC EXITEQUAL
    SETB Negative
EXITEQUAL:
    JB Negative, CONVERT
    SJMP RESET2
CONVERT:
    CLR C
    MOV A, #0
    SUBB A, dispBuf+3
    ACALL DAAA
    MOV dispBuf+3, A
    MOV preValue+3, A
    MOV A, #0
    SUBB A, dispBuf+2
    ACALL DAAA
    MOV dispBuf+2, A
    MOV preValue+2, A
    MOV A, #0
    SUBB A, dispBuf+1
    ACALL DAAA
    MOV dispBuf+1, A
    MOV preValue+1, A
    MOV A, #0
    SUBB A, dispBuf
    ACALL DAAA
    MOV dispBuf, A
    MOV preValue, A
    SJMP RESET2 
SETDIGITS:
    PUSH 0E0h
    MOV dispBuf, A
    MOV dispBuf+1, A
    MOV dispBuf+2, A
    MOV dispBuf+3, A
    POP 0E0h
    RET
DISPLAYKEYPATTERN:
    PUSH 0E0h
    MOV dispBuf,dispBuf+1
    MOV dispBuf+1,dispBuf+2
    MOV dispBuf+2,dispBuf+3
    MOV dispBuf+3,keyCode
    POP 0E0h
    RET 
DAAA:
    ANL A, #0Fh
    JNC EXITDAAA
    SUBB A, #5
    JNC LEAVEDAAA
    ADD A, #6
LEAVEDAAA:
    SETB C
EXITDAAA:
    RET
TRANSFORM:
    DB 0Eh
    DB 0Ch
    DB 0Ch
    DB 0Dh
    DB 0Ch
    DB 03h
    DB 06h
    DB 09h
    DB 0Fh
    DB 02h
    DB 05h
    DB 08h
    DB 00h
    DB 01h
    DB 04h
    DB 07h
LED_TABLE:
    DB 0C0h
    DB 0F9h
    DB 0A4h
    DB 0B0h
    DB 099h
    DB 092h
    DB 082h
    DB 0D8h
    DB 080h
    DB 090h
    DB 088h
    DB 083h
    DB 0FFh
    DB 0BFh
    DB 0FFh
    DB 0C0h
    END