keypad.lst

keyboard Realizing the keyboard control digital tube

MPASM 03.00 Released           KEYPAD.ASM   8-28-2005  20:25:49         PAGE  1


LOC  OBJECT CODE     LINE SOURCE TEXT
  VALUE

                      00001 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
                      00002 ; 
                      00003 ;       KEYPAD.ASM      MPB     Ver 1.0         28-8-05 
                      00004 ; 
                      00005 ;       Reads keypad and shows digit on display
                      00006 ;       Design file KEYPAD.DSN
                      00007 ; 
                      00008 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
                      00009  
                      00010         PROCESSOR 16F877
                      00011 
  00000002            00012 PCL     EQU     002             ; Program Counter
  00000007            00013 PORTC   EQU     007             ; 7-Segment display
  00000008            00014 PORTD   EQU     008             ; 3x4 keypad
                      00015 
  00000087            00016 TRISC   EQU     087             ; Data direction
  00000088            00017 TRISD   EQU     088             ; registers
                      00018 
  00000020            00019 Key     EQU     020             ; Count of keys
                      00020 
                      00021 ; Initialise ports.........................................
                      00022 
0000   1683 1303      00023         BANKSEL TRISC           ; Display
0002   0103           00024         CLRW                    ; all outputs
Message[302]: Register in operand not in bank 0.  Ensure that bank bits are correct.
0003   0087           00025         MOVWF   TRISC           ; 
0004   3007           00026         MOVLW   B'00000111'     ; Keypad
Message[302]: Register in operand not in bank 0.  Ensure that bank bits are correct.
0005   0088           00027         MOVWF   TRISD           ; bidirectional
                      00028 
0006   1283 1303      00029         BANKSEL PORTC           ; Display off
0008   0187           00030         CLRF    PORTC           ; initially
0009   2830           00031         GOTO    main            ; jump to main
                      00032 
                      00033 ; Check a row of keys .....................................
                      00034 
Message[305]: Using default destination of 1 (file).
000A   0AA0           00035 row     INCF    Key             ; Count first key
000B   1C08           00036         BTFSS   PORTD,0         ; Check key
000C   281D           00037         GOTO    found           ; and quit if on
                      00038 
Message[305]: Using default destination of 1 (file).
000D   0AA0           00039         INCF    Key             ; and repeat
000E   1C88           00040         BTFSS   PORTD,1         ; for second 
000F   281D           00041         GOTO    found           ; key
                      00042 
Message[305]: Using default destination of 1 (file).
0010   0AA0           00043         INCF    Key             ; and repeat
0011   1D08           00044         BTFSS   PORTD,2         ; for third
0012   281D           00045         GOTO    found           ; key
0013   2818           00046         GOTO    next            ; go for next row
                      00047 
                      00048 ; Scan the keypad..........................................
MPASM 03.00 Released           KEYPAD.ASM   8-28-2005  20:25:49         PAGE  2


LOC  OBJECT CODE     LINE SOURCE TEXT
  VALUE

                      00049 
0014   01A0           00050 scan    CLRF    Key             ; Zero key count 
0015   1403           00051         BSF     3,0             ; Set Carry Flag 
0016   1208           00052         BCF     PORTD,4         ; Select first row
0017   280A           00053 newrow  GOTO    row             ; check row
                      00054 
0018   1588           00055 next    BSF     PORTD,3         ; Set fill bit
Message[305]: Using default destination of 1 (file).
0019   0D88           00056         RLF     PORTD           ; Select next row
001A   1803           00057         BTFSC   3,0             ; 0 into carry flag?
001B   2817           00058         GOTO    newrow          ; if not, next row
001C   2814           00059         GOTO    scan            ; if so, start again
                      00060 
001D   0008           00061 found   RETURN                  ; quit with key count
                      00062 
                      00063 ; Display code table.......................................
                      00064 
001E   0820           00065 table   MOVF    Key,W           ; Get key count
Message[305]: Using default destination of 1 (file).
001F   0782           00066         ADDWF   PCL             ; and calculate jump
0020   0000           00067         NOP                     ; into table 
0021   340C           00068         RETLW   B'00001100'     ; Code for '1'
0022   34B6           00069         RETLW   B'10110110'     ; Code for '2'
0023   349E           00070         RETLW   B'10011110'     ; Code for '3'
0024   34CC           00071         RETLW   B'11001100'     ; Code for '4'
0025   34DA           00072         RETLW   B'11011010'     ; Code for '5'
0026   34F8           00073         RETLW   B'11111000'     ; Code for '6'
0027   340E           00074         RETLW   B'00001110'     ; Code for '7'  
0028   34FE           00075         RETLW   B'11111110'     ; Code for '8'
0029   34CE           00076         RETLW   B'11001110'     ; Code for '9'
002A   3492           00077         RETLW   B'10010010'     ; Code for '*'
002B   347E           00078         RETLW   B'01111110'     ; Code for '0'
002C   34EC           00079         RETLW   B'11101100'     ; Code for '#'
                      00080 
                      00081 ; Output display code......................................
                      00082 
002D   201E           00083 show    CALL    table           ; Get display code
002E   0087           00084         MOVWF   PORTC           ; and show it
002F   0008           00085         RETURN
                      00086 
                      00087 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
                      00088 
                      00089 ; Read keypad & display....
                      00090 
0030   30FF           00091 main    MOVLW   0FF             ; Set all outputs 
0031   0088           00092         MOVWF   PORTD           ; to keypad high
0032   2014           00093         CALL    scan            ; Get key number
0033   202D           00094         CALL    show            ; and dsiplay it
0034   2830           00095         GOTO    main            ; and repeat
                      00096         END
MPASM 03.00 Released           KEYPAD.ASM   8-28-2005  20:25:49         PAGE  3


SYMBOL TABLE
  LABEL                             VALUE 

Key                               00000020
PCL                               00000002
PORTC                             00000007
PORTD                             00000008
TRISC                             00000087
TRISD                             00000088
__16F877                          00000001
found                             0000001D
main                              00000030
newrow                            00000017
next                              00000018
row                               0000000A
scan                              00000014
show                              0000002D
table                             0000001E


MEMORY USAGE MAP ('X' = Used,  '-' = Unused)

0000 : XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX XXXXX-----------

All other memory blocks unused.

Program Memory Words Used:    53
Program Memory Words Free:  8139


Errors   :     0
Warnings :     0 reported,     0 suppressed
Messages :     7 reported,     0 suppressed