,,,;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
,,,;
,,,;       Source File:    BIN4D.ASM
,,,;       Author:         MPB
,,,;       Date:           13-11-05
,,,;
,,,;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
,,,;
,,,;       Slow output binary count is stopped, started
,,,;       and reset with push buttons.
,,,;       Modified with extra directives
,,,;
,,,;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
,,,
,,,;       Declare processor, supress messages and warnings,
,,,;       do not print symbol table, and configure (RC clock)
,,,
,,,        LIST p=16f877a, w=2, st=off, mm=off
00002007,3733,,        __CONFIG 0x3733
,,,
,,,;       Declare GPR label and literal constant
,,,;       Define input labels
,,,;       Include standard SFR label file
,,,;       Include PortB initialisation file
,,,
,,,Timer EQU 20
,,,DDCodeB SET b'00000000'
,,,CONSTANT Count=0FF
,,,#DEFINE RunBut PORTD,1
,,,#DEFINE ResBut PORTD,0
,,,#INCLUDE "P16F877A.INC"
,,,#INCLUDE <BOUT.INI>
00000000,1683 1303,,        BANKSEL TRISB           ; Select bank 1
00000002,3000,,        MOVLW   DDCodeB         ; Port B Direction Code
00000003,0086,,        MOVWF   TRISB           ; Load the DDR code into F86
00000004,1283 1303,,        BANKSEL PORTB           ; Select bank 0
,,,
,,,; Program code ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
,,,
,,,; 'delay' macro .............................................
,,,
,,,delay   MACRO                   ; macro definition starts
,,,        MOVWF   Timer           ; Copy W to timer register
,,,down    DECF    Timer           ; Decrement timer register
,,,        BNZ     down            ; and repeat until zero
,,,        ENDM                    ; macro definition ends
,,,
,,,; Main loop .................................................
,,,
00000006,0186,reset,reset   CLRF    PORTB           ; Clear Port B Data
,,,
00000007,1C08,start,start   BTFSS   ResBut          ; Test reset button
00000008,2806,,        GOTO    reset           ; and reset Port B if pressed
00000009,1888,,        BTFSC   RunBut          ; Test run button
0000000A,2807,,        GOTO    start           ; and repeat if n pressed
,,,
0000000B,0A86,,        INCF    PORTB           ; Increment output at Port B
0000000C,30FF,,        MOVLW   Count           ; Delay count literal
,,,        delay                   ; Jump to subroutine 'delay'
0000000D,00A0,,        - MOVWF   Timer           ; Copy W to timer register
0000000E,03A0,down,- down    DECF    Timer           ; Decrement timer register
0000000F,1D03 280E,,        - BNZ     down            ; and repeat until zero
00000011,2807,,        GOTO    start           ; Repeat main loop always
,,,
,,,        END                     ; Terminate source code......