beginners/pld_stily.asm

   1 ;
   2 ; pld for stily (and yvonne) ;)
   3 ;
   4 ; author: hackbard@hackdaworld.org
   5 ;
   6
   7 .include "../include/m163def.inc"
   8
   9 INIT:
  10 ldi r30,0x00 ; light status
  11 ldi r28,1 ; constants
  12 ldi r27,0x01;
  13 out DDRC,r27 ; select pin 0 as output
  14 rjmp LIGHT
  15
  16 LIGHT:
  17 cpi r30,0x00
  18 breq LIGHT_ON
  19 rjmp LIGHT_OFF
  20
  21 LIGHT_ON:
  22 ldi r31,0 ; reset wait counter
  23 ldi r30,0x01
  24 out PORTC,r30
  25 rjmp WAIT
  26
  27 LIGHT_OFF:
  28 ldi r31,0
  29 ldi r30,0x00
  30 out PORTC,r30
  31 rjmp WAIT
  32
  33 WAIT:
  34 ldi r29,0 ; reset inner wait counter
  35 add r31,r28 ; increment wait counter
  36 cpi r31,0xff ; after 255 steps
  37 breq LIGHT
  38 rjmp WAIT_MORE
  39
  40 WAIT_MORE:
  41 ldi r25,0 ; reset inner inner wait counter
  42 add r29,r28 ; increment inner wait loop counter
  43 cpi r29,0xff ; goto first wait loop after 255 cycles
  44 breq WAIT
  45 rjmp WAIT_MORE_MORE
  46
  47 WAIT_MORE_MORE:
  48 add r25,r28 ; inc inner inner wait counter
  49 cpi r25,0x05 ; goto wait_more loop
  50 breq WAIT_MORE
  51 rjmp WAIT_MORE_MORE