;**************************************************************************
; Input.ASM
;
; This is a simple test of switches
;
; Uses switches connected to RA0 and RA1 to turn LED on or off
;
;**************************************************************************

        LIST      P=16F84, R=DEC
        __FUSES   _XT_OSC &  _WDT_OFF & _CP_OFF & _PWRTE_ON
        include   "P16F84.inc"

;--------------------------------------------------------------------------
; Variables
;--------------------------------------------------------------------------

Ram             EQU     h'0C'


;--------------------------------------------------------------------------
; Program Code
;--------------------------------------------------------------------------

                ORG     0               ;reset vector
Start           call    Init            ;Initialise hardware

Loop            btfss   PORTA, 0        ;Is "ON" button pressed?
                bsf     PORTB, 0        ;  Yes - LED on
                btfss   PORTA, 1        ;Is "OFF" button pressed?
                bcf     PORTB, 0        ;  Yes - LED off
                goto    Loop            ;



;--------------------------------------------------------------------------
; Subroutines
;--------------------------------------------------------------------------

;*****Init - set up all ports, make unused ports outputs

Init            clrf    PORTA           ;all of porta low
                clrf    PORTB           ;all of portb low

                bsf     STATUS, RP0     ;change to bank1
                movlw   b'00000011'     ;all outputs except RA0, 1
                movwf   TRISA           ;
                movlw   b'00000000'     ;all outputs
                movwf   TRISB           ;
                bcf     STATUS, RP0     ;back to bank0

                return

                END                     ;Stop assembling here