;3*3鍵盤程序，使用C口作鍵盤掃描，7段數碼管顯示按鍵號
;63系列通用寄存器地址：20~7FH, A0~FFH

;未達到預期目的，只用個位數顯示按鍵號時正常工作，增加按鍵號轉換（用2位數顯示）
;則提示“STACK OVERFLOW"--堆棧溢出.編譯后機器碼容量為1.3KB左右，未超過CALL跳轉范圍——1頁（2K）

#include P16C63A.INC
KEYCODE EQU  H'0020'
KEYNUM  EQU  H'0021'
CC    EQU  H'0024'
TABADD EQU H'0025'
SW   EQU H'0026'
GW   EQU H'0027'
;PD   EQU H'0028'

ORG H'0000'
GOTO MAIN
ORG H'0010'

MAIN  MOVLW H'00'
      TRIS PORTA
      TRIS PORTB ;RB口全為輸出，用作驅動7段數碼管
      MOVWF KEYNUM
      MOVLW H'F0' 
      TRIS PORTC ;  設置RC低四位為輸出，高四位為輸入
      MOVLW TABLE
      MOVWF TABADD
      MOVLW H'0001'
;      MOVWF PD   ;用來判斷按鍵號是否大于9

LOOP  
      CALL KEYSCAN
   ;   CALL JUDGE     ;判斷是按鍵號是否大于9
   ;   XORLW H'0001'
   ;   BTFSS STATUS,Z
       CALL XIAO
   ;   GOTO DASHU
XS    CALL DISP_2
      GOTO LOOP    ;循環掃描、顯示按鍵號

JUDGE     
      MOVLW H'0A'
      SUBWF KEYNUM,0
      BTFSC STATUS,0  ; C標志
   ;   RETLW 0  ;小于10
   ;   RETLW 1  ; 10以上的按鍵號
      GOTO XIAO
      GOTO DASHU

XIAO  MOVLW 0
      MOVWF SW
      MOVF KEYNUM,0
      MOVWF GW
      RETLW 0
     ; GOTO XS

DASHU  
      MOVLW H'01'
      MOVWF SW
      MOVLW H'0A'
      SUBWF KEYNUM,0
      MOVWF GW
      RETLW 0
     ; GOTO XS 

DISP_2
      MOVLW H'02'
      MOVWF PORTA
      MOVF SW,0
      CALL DISP
      CALL DELAY

      MOVLW H'01'
      MOVWF PORTA
      MOVF GW,0
      CALL DISP
      CALL DELAY
      RETLW 0

DELAY MOVLW 0
      MOVWF CC
LL    DECFSZ CC,1
      GOTO LL
      RETLW 0
   
DISP  ; MOVF KEYNUM,0                    ;輸入W,輸出W
      ADDWF TABADD,0 
      CALL CONV
      MOVWF PORTB
      RETLW 0
CONV  MOVWF PCL   ;取碼，輸入W（0～F），輸出W
TABLE RETLW H'C0'
      RETLW H'F9'
      RETLW H'A4'
      RETLW H'B0'
      RETLW H'99'
      RETLW H'92'
      RETLW H'82'
      RETLW H'F8'
      RETLW H'80'
      RETLW H'90'
      RETLW H'88'
      RETLW H'83'
      RETLW H'C6' 
      RETLW H'A1'
      RETLW H'86'
      RETLW H'8E'    ;0~F 數碼管代碼
      RETLW H'C0'
      
KEYSCAN  MOVLW H'FE'  ;第一行置低（RC0輸出0）
         MOVWF PORTC
         NOP
         MOVF PORTC,0 ;讀RC各端口狀態
         ANDLW H'F0' ;屏蔽低四位，只需要低四位來判斷
         MOVWF KEYCODE ;保存端口狀態
         MOVLW H'F0'
         SUBWF KEYCODE,0 ;與初值比較，看是否有鍵按下
         BTFSS STATUS,Z  ;有鍵按下（不等于初值，Z為零）則結束掃描
         GOTO  GETNUM1

         MOVLW H'FD'  ;第二行置低（RC1輸出0）
         MOVWF PORTC
         NOP
         MOVF PORTC,0 ;讀RC各端口值
         ANDLW H'F0' ;屏蔽低四位，只需要低四位來判斷
         MOVWF KEYCODE ;保存端口狀態
         MOVLW H'F0'
         SUBWF KEYCODE,0 ;與初值比較，看是否有鍵按下
         BTFSS STATUS,Z  ;有鍵按下（不等于初值，Z為零）則結束掃描
         GOTO  GETNUM2

         MOVLW H'FB'  ;第三行置低（RC2輸出0）
         MOVWF PORTC
         NOP
         MOVF PORTC,0 ;讀RC各端口值
         ANDLW H'F0' ;屏蔽低四位，只需要低四位來判斷
         MOVWF KEYCODE ;保存端口狀態
         MOVLW H'F0'
         SUBWF KEYCODE,0 ;與初值比較，看是否有鍵按下
         BTFSS STATUS,Z  ;有鍵按下（不等于初值，Z為零）則結束掃描
         GOTO  GETNUM3

         MOVLW H'F7'  ;第四行置低（RC3輸出0）
         MOVWF PORTC
         NOP
         MOVF PORTC,0 ;讀RC各端口值
         ANDLW H'F0' ;屏蔽低四位，只需要低四位來判斷
         MOVWF KEYCODE ;保存端口狀態
         MOVLW H'F0'
         SUBWF KEYCODE,0 ;與初值比較，看是否有鍵按下
         BTFSS STATUS,Z  ;有鍵按下（不等于初值，Z為零）則結束掃描
         GOTO  GETNUM4
FH       RETLW  0    ; 子程序返回

QUDOU    MOVF PORTC,0  ;去抖處理
         SUBWF KEYCODE,0
         BTFSC STATUS,Z
         GOTO QUDOU
         GOTO FH

GETNUM1  MOVLW H'E0'  ;1號鍵
         SUBWF KEYCODE,0 
         BTFSC STATUS,Z
         GOTO NUM1
         MOVLW H'D0'  ;2號鍵
         SUBWF KEYCODE,0 
         BTFSC STATUS,Z
         GOTO NUM2
         MOVLW H'B0'  ;3號鍵
         SUBWF KEYCODE,0 
         BTFSC STATUS,Z
         GOTO NUM3
         MOVLW H'70'  ;4號鍵
         SUBWF KEYCODE,0 
         BTFSC STATUS,Z
         GOTO NUM4         
         GOTO FH

GETNUM2  MOVLW H'E0'  ;5號鍵
         SUBWF KEYCODE,0 
         BTFSC STATUS,Z
         GOTO NUM5
         MOVLW H'D0'  ;6號鍵
         SUBWF KEYCODE,0
         BTFSC STATUS,Z
         GOTO NUM6 
         MOVLW H'B0'  ;7號鍵
         SUBWF KEYCODE,0
         BTFSC STATUS,Z
         GOTO NUM7 
         MOVLW H'70'  ;8號鍵
         SUBWF KEYCODE,0 
         BTFSC STATUS,Z
         GOTO NUM8
         GOTO FH

GETNUM3  MOVLW H'E0'  ;9號鍵
         SUBWF KEYCODE,0
         BTFSC STATUS,Z
         GOTO NUM9 
         MOVLW H'D0'  ;10號鍵
         SUBWF KEYCODE,0
         BTFSC STATUS,Z
         GOTO NUM10 
         MOVLW H'B0'  ;11號鍵
         SUBWF KEYCODE,0
         BTFSC STATUS,Z
         GOTO NUM11 
         MOVLW H'70'  ;12號鍵
         SUBWF KEYCODE,0 
         BTFSC STATUS,Z
         GOTO NUM12
         GOTO FH

GETNUM4  MOVLW H'E0'  ;13號鍵
         SUBWF KEYCODE,0
         BTFSC STATUS,Z
         GOTO NUM13 
         MOVLW H'D0'  ;14號鍵
         SUBWF KEYCODE,0
         BTFSC STATUS,Z
         GOTO NUM14 
         MOVLW H'B0'  ;15號鍵
         SUBWF KEYCODE,0
         BTFSC STATUS,Z
         GOTO NUM15 
         MOVLW H'70'  ;16號鍵
         SUBWF KEYCODE,0 
         BTFSC STATUS,Z
         GOTO NUM16
         GOTO FH

NUM1     MOVLW 1
         MOVWF KEYNUM
         GOTO QUDOU 
NUM2     MOVLW 2
         MOVWF KEYNUM
         GOTO QUDOU 
NUM3     MOVLW 3
         MOVWF KEYNUM
         GOTO QUDOU 
NUM4     MOVLW 4
         MOVWF KEYNUM
         GOTO QUDOU 
NUM5     MOVLW 5
         MOVWF KEYNUM
         GOTO QUDOU 
NUM6     MOVLW 6
         MOVWF KEYNUM
         GOTO QUDOU 
NUM7     MOVLW 7
         MOVWF KEYNUM
         GOTO QUDOU 
NUM8     MOVLW 8
         MOVWF KEYNUM
         GOTO QUDOU
NUM9     MOVLW 9
         MOVWF KEYNUM
         GOTO QUDOU 
NUM10     MOVLW H'000A'
         MOVWF KEYNUM
         GOTO QUDOU 
NUM11     MOVLW H'000B'
         MOVWF KEYNUM
         GOTO QUDOU 
NUM12     MOVLW H'000C'
         MOVWF KEYNUM
         GOTO QUDOU
NUM13     MOVLW H'000D'
         MOVWF KEYNUM
         GOTO QUDOU
NUM14     MOVLW H'000E'
         MOVWF KEYNUM
         GOTO QUDOU 
NUM15     MOVLW H'000F'
         MOVWF KEYNUM
         GOTO QUDOU 
NUM16     MOVLW H'0010'
         MOVWF KEYNUM
         GOTO QUDOU

  END