;ledswich.asm

;4 LEDs on PORTB, 4 switches on PORTD
;PORTD0 SWITCH -----> PORTB0 LED
;PORTD1 SWITCH -----> PORTB1 LED
;PORTD2 SWITCH -----> PORTB2 LED
;PORTD3 SWITCH -----> PORTB3 LED
;Press one or more switches and corresponding LEDs will lightup

;assembled using Atmel's avrasm assembler.


;the following .inc file should be placed in the same directory as
;this assembly program

.include "1200def.inc"

.cseg
.org 0
         rjmp    RESET           ;Reset Handle
         rjmp    RESET
         rjmp    RESET

RESET:   ldi r16, 0b11111111     ;load register r16 with all 1's
         out DDRB, r16           ;configure PORT B for all outputs

         ldi r16, 0b00000000     ;load register r16 with all 0's
         out DDRD, r16           ;configure PORTD for all inputs

loopit:  in r16, PIND            ;read the state of the pin on PORTD
                                 ;into r16 register
         out PORTB, r16          ;and copy it to PORTB
         rjmp loopit