#include <p16F690.inc>
__config (_INTRC_OSC_NOCLKOUT & _WDT_OFF & _PWRTE_OFF & _MCLRE_OFF & _CP_OFF & _BOR_OFF & _IESO_OFF & _FCMEN_OFF)
org 0
Start:
bsf STATUS,RP0 ;select Register Page 1
clrf TRISC ;make make port C outputs
bcf STATUS,RP0 ;back to Register Page 0
bsf STATUS,RP1 ;page 2
clrf ANSEL ;turn off ADC
bcf STATUS,RP1 ;back to page 0
movlw 1 ;turn on LED
movwf PORTC ;on port C
Loop
btfss PORTA,0 ;skip if port A high
bcf PORTC,0 ;else set Port C low
btfsc PORTA,0 ;skip if port A low
bsf PORTC,0 ;else set Port C high
goto Loop ;repeat forever
end