;-------4*4鍵盤程序的使用--------
PC?????? EQU??? 2
STATUS?? EQU??? 3
RA?????? EQU??? 5
RB?????? EQU??? 6
RC?????? EQU??? 7
BIJIAO?? EQU??? 0F
JIANZHI? EQU??? 8
BUFFER?? EQU??? 9
BUFFER1? EQU??? 0AH
BUFFER2? EQU??? 0BH
COUNTER? EQU??? 0CH
CON1???? EQU??? 0DH
CON2???? EQU??? 0EH
PIC57??? EQU??? 7FFH
Z??????? EQU??? 2
;-----------------------------
???????? ORG??? PIC57
???????? GOTO?? MAIN
;-----------------------------
???????? ORG??? 0
;-----------------------------
;??????? 延時子程序
;----------------------------
DELAY??? MOVLW? D'100'
???????? MOVWF? CON1
L1?????? MOVLW? D'200'
???????? MOVWF? CON2
L2?????? DECFSZ CON2,1
???????? GOTO?? L2
???????? DECFSZ CON1,1
???????? GOTO?? L1
???????? RETLW? 0????????
;-----------------------------
;??????? 4*4鍵盤掃描判斷子程序
;-----------------------------
SCANKEY
???????? MOVLW? B'11101111'
???????? MOVWF? RB
???????? MOVF?? RB,W
???????? ANDLW? B'00001111'
???????? MOVWF? BUFFER
???????? MOVLW? B'00001111'
???????? XORWF? BUFFER,W
???????? SKPNZ
???????? GOTO?? XYB1
???????? MOVWF? BUFFER1
???????? MOVLW? 1
???????? MOVWF? JIANZHI
???????? MOVF?? RB,W
???????? MOVWF? BIJIAO
???????? GOTO?? QJZ

XYB1???? MOVLW? B'11011111'
???????? MOVWF? RB
???????? MOVF?? RB,W
???????? ANDLW? B'00001111'
???????? MOVWF? BUFFER
???????? MOVLW? B'00001111'
???????? XORWF? BUFFER,W
???????? SKPNZ
???????? GOTO?? XYB2
???????? MOVWF? BUFFER1
???????? MOVLW? 5
???????? MOVWF? JIANZHI
???????? GOTO?? QJZ

XYB2???? MOVLW? B'10111111'
???????? MOVWF? RB
???????? MOVF?? RB,W
???????? ANDLW? B'00001111'
???????? MOVWF? BUFFER
???????? MOVLW? B'00001111'
???????? XORWF? BUFFER,W
???????? SKPNZ
???????? GOTO?? XYB3
???????? MOVWF? BUFFER1
???????? MOVLW? 9
???????? MOVWF? JIANZHI
???????? MOVF?? RB,W
???????? MOVWF? BIJIAO
???????? GOTO?? QJZ

XYB3???? MOVLW? B'01111111'
???????? MOVWF? RB
???????? MOVF?? RB,W
???????? ANDLW? B'00001111'
???????? MOVWF? BUFFER
???????? MOVLW? B'00001111'
???????? XORWF? BUFFER,W
???????? SKPNZ
???????? RETLW? 0
???????? MOVWF? BUFFER1
???????? MOVLW? 0DH
???????? MOVWF? JIANZHI
???????? MOVF?? RB,W
???????? MOVWF? BIJIAO

QJZ????? MOVLW? 1
???????? MOVWF? BUFFER2
???????? MOVLW? 4
???????? MOVWF? COUNTER

QJZ1???? MOVF?? BUFFER1,W
???????? SUBWF? BUFFER2,W
???????? SKPNZ
???????? RETLW? 1
???????? RLF??? BUFFER2,1
???????? INCF?? JIANZHI,1
???????? DECFSZ COUNTER,1
???????? GOTO?? QJZ1
???????? RETLW? 0
;-------------------------------
;??? 測試程序(注意用法,鍵值放在JIANZHI里)
;-------------------------------
MAIN
???????? MOVLW? 0
???????? TRIS?? RC
???????? CLRF?? RC
???????? MOVLW? B'00001111'???? ;用RB口作4*4鍵盤
???????? TRIS?? RB
LOOP???? CLRF?? RC
???????? CALL?? SCANKEY
???????? ANDLW? 0FH
???????? SKPNZ????????????????? ;根據返回值不為零,判斷有無鍵按下
???????? GOTO?? LOOP
???????? MOVLW? 0FH
???????? ANDWF? JIANZHI,W
???????? MOVWF? RC
???????? CALL?? DELAY
LOOP1??? MOVF?? BUFFER1,W
???????? ANDWF? RB,W
???????? XORWF? BIJIAO,W
???????? SKPNZ
???????? GOTO?? LOOP1
???????? GOTO?? LOOP
;--------------
;-------------------------------
???????? END

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