beginners/test_port_d.asm

   1 ;
   2 ; portd 3-7 blinken lights ;)
   3 ;
   4 ; author: hackbard@hackdaworld.dyndns.org
   5 ;
   6
   7 .include "../include/2313def.inc"
   8
   9 INIT:
  10 ldi r30,2 ; light counter
  11 ldi r28,1 ; constants
  12 ldi r27,0x7f ;
  13 out DDRD,r27 ; select all pins as output
  14 rjmp LIGHT
  15
  16 LIGHT:
  17 ldi r31,0 ; reset wait counter
  18 lsl r30
  19 cpi r30,128
  20 breq RESET_L
  21 ldi r16,0xff
  22 sub r16,r30
  23 out PORTD,r16
  24 rjmp WAIT
  25
  26 RESET_L:
  27 ldi r30,2 ; again start with 1
  28 rjmp LIGHT
  29
  30 WAIT:
  31 ldi r29,0 ; reset inner wait counter
  32 add r31,r28 ; increment wait counter
  33 cpi r31,0xff ; after 255 steps
  34 breq LIGHT
  35 rjmp WAIT_MORE
  36
  37 WAIT_MORE:
  38 ldi r25,0 ; reset inner inner wait counter
  39 add r29,r28 ; increment inner wait loop counter
  40 cpi r29,0xff ; goto first wait loop after 255 cycles
  41 breq WAIT
  42 rjmp WAIT_MORE_MORE
  43
  44 WAIT_MORE_MORE:
  45 add r25,r28 ; inc inner inner wait counter
  46 cpi r25,0x05 ; goto wait_more loop
  47 breq WAIT_MORE
  48 rjmp WAIT_MORE_MORE