openinterval.asm

   1 ;   OpenInterval
   2 ;
   3 ;   Copyright 2007 Matthew F. Coates (mattjackets+openinterval at gmail.com)
   4 ;
   5 ;   This program is free software: you can redistribute it and/or modify
   6 ;   it under the terms of the GNU General Public License as published by
   7 ;   the Free Software Foundation, either version 3 of the License, or
   8 ;   (at your option) any later version.
   9 ;
  10 ;   This program is distributed in the hope that it will be useful,
  11 ;   but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 ;   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 ;   GNU General Public License for more details.
  14 ;
  15 ;   You should have received a copy of the GNU General Public License
  16 ;   along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 .include "include/tn12def.inc"
  19 .EQU buttonPin  = 1 ; button
  20 .EQU syncPin    = 3 ; sync LED port
  21 .EQU irPort     = PORTB; ir LED port
  22 .EQU irPin      = 4 ; ir LED pin
  23 .equ FREQ       = 0 ; start out with no interval
  24
  25 .def temp       = r16
  26 .def tcounter   = r17
  27 .def tcounter2  = r18
  28 .def mode       = r19
  29 .def DelayReg2  = r24
  30
  31 .cseg
  32 .org 0x0000
  33
  34 reset:
  35         rjmp    init            ; Reset handler
  36         rjmp    INT0_hand       ; INT0 handler
  37         reti                    ; Pin change handler
  38         rjmp    TIM0_OVF        ; Timer0 overflow handler
  39         reti                    ; EEPROM Ready handler
  40         reti                    ; Analog Comparator handler
  41
  42 ;camera include file goes here
  43 .include "cameras/Nikon_OML-L3.inc"
  44
  45 init:
  46 ; enable sleep mode and INT0 on falling edge
  47         ldi     temp, (1 << SE) | (1 << ISC01) & (0 << ISC00)
  48         out     MCUCR, temp
  49
  50 ; disable ACD
  51         ldi     temp, (1 << ACD)
  52         out     ACSR, temp
  53
  54 ; enable timer0
  55 ;       ldi     temp, 0
  56 ;       out     TCNT0, temp
  57
  58 ; set timer prescaler 1024
  59         ldi     temp, (1 << CS02) | (1 << CS00)
  60         out     TCCR0, temp
  61
  62 ; enable timer overflow
  63         ldi     temp, (1 << TOIE0)
  64         out     TIMSK, temp
  65
  66 ; enable INT0 interrupt
  67         ldi     temp, (1 << INT0)
  68         out     GIMSK, temp
  69
  70         ldi     temp,0
  71         ldi     DelayReg,FREQ
  72         ldi     tcounter,FREQ
  73         ldi     mode,0
  74
  75 ; Set portB input
  76         sbi     PORTB,buttonPin ; set b4 config. to enable internal pull-up.
  77         cbi     DDRB,buttonPin
  78 ; Set portB output
  79         sbi     DDRB,irPin
  80         sbi     DDRB,syncPin
  81
  82         sbi     irPort,irPin    ; LED off
  83         rcall   shutterrelease
  84         sei
  85
  86 GoToSleep:
  87         sleep
  88         rjmp    GoToSleep
  89
  90 TIM0_OVF:       ; -- handle timer0 overflow, trigger shutter
  91         cpi     mode,1
  92         breq    TIMING
  93         sbi     portb,syncPin
  94         cpi     tcounter2, 0
  95         brne    SKIP
  96         cpi     tcounter,0
  97         brne    SKIP
  98         cbi     portb,syncPin
  99         mov     tcounter, DelayReg
 100         rcall   shutterrelease
 101 skip:
 102         dec     tcounter
 103         cpi     tcounter,0
 104         breq    dectcounter2
 105         reti
 106 DecTCounter2:
 107         dec     tcounter2
 108         reti
 109 Timing:
 110         inc     DelayReg
 111         cpi     DelayReg,0
 112         breq    INCDelayReg2
 113         reti
 114
 115 INCDelayReg2:
 116         inc     DelayReg2
 117         reti
 118
 119 INT0_hand:
 120         ldi     Counter,255
 121 intpause:
 122         rcall   delay130
 123         rcall   delay130
 124         rcall   delay130
 125         rcall   delay130
 126         rcall   delay130
 127         rcall   delay130
 128         rcall   delay130
 129         rcall   delay130
 130         rcall   delay130
 131         rcall   delay130
 132         rcall   delay130
 133         rcall   delay130
 134         rcall   delay130
 135         rcall   delay130
 136         rcall   delay130
 137         rcall   delay130
 138         rcall   delay130
 139         rcall   delay130
 140         rcall   delay130
 141         rcall   delay130
 142         rcall   delay130
 143         rcall   delay130
 144         rcall   delay130
 145         rcall   delay130
 146         rcall   delay130
 147         dec     Counter
 148         brne    intpause
 149
 150         cpi     mode,1
 151         breq    setdelay
 152
 153 ; enable timer0
 154         ldi     temp, 0
 155         out     TCNT0, temp
 156         cbi     portb,SyncPin
 157         ldi     mode,1 ; timing mode
 158         reti
 159
 160 SetDelay:
 161         sbi     portb,syncPin
 162         mov     tcounter,DelayReg
 163         mov     tcounter2,DelayReg2
 164         ldi     mode,2 ; running mode
 165
 166         reti