;
; efe.blink.asm
; (c) Neil Gershenfeld CBA MIT 10/16/04
; blink the LED
;

.include "tn15def.inc"
.equ ledpin = PB4; LED pin
.def temp = R17; temporary storage
.def temp1 = R18; temporary storage

.cseg
.org 0
rjmp reset

;
; delay
;
.equ count = 255
delay:
   ldi temp1, count
   delay_loop1:
      ldi temp, count
      delay_loop:
         dec temp
         brne delay_loop	
      dec temp1
      brne delay_loop1
   ret
;
; main program
;
reset:
   ldi temp, 0xff ; maximum RC clock
   out OSCCAL, temp
   sbi PORTB, ledpin; init LED pin
   sbi DDRB, ledpin
   loop:
      sbi PORTB, ledpin
      rcall delay
      cbi PORTB, ledpin
      rcall delay
      rjmp loop