;;
  ;;  mur.sat
  ;;
  ;;  Somewhen in the year 2011, mur.at will have a nano satellite launched
  ;;  into a low earth orbit (310 km above the surface of our planet). The
  ;;  satellite itself is a TubeSat personal satellite kit, developed and
  ;;  launched by interorbital systems. mur.sat is a joint venture of mur.at,
  ;;  ESC im Labor and realraum.
  ;;
  ;;  Please visit the project hompage at sat.mur.at for further information.
  ;; 
  ;;
  ;;  Copyright (C) 2011 Christian Pointner <equinox@spreadspace.org>
  ;;                         
  ;;  This file is part of mur.sat.
  ;;
  ;;  mur.sat is free software: you can redistribute it and/or modify
  ;;  it under the terms of the GNU General Public License as published by
  ;;  the Free Software Foundation, either version 3 of the License, or
  ;;  any later version.
  ;;
  ;;  mur.sat is distributed in the hope that it will be useful,
  ;;  but WITHOUT ANY WARRANTY; without even the implied warranty of
  ;;  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  ;;  GNU General Public License for more details.
  ;;
  ;;  You should have received a copy of the GNU General Public License
  ;;  along with mur.sat. If not, see <http://www.gnu.org/licenses/>.
  ;;
  ;; -------------------------------------
  ;; PREAMBLE

  LIST      p=10F206
  include   "p10f206.inc"
  __config  _MCLRE_OFF & _CP_OFF & _WDT_OFF

  ;; -------------------------------------
  ;; DEFINES
BEACON_INT  EQU .60
SECCNT      EQU H'0008'

DOT         EQU .36
DASH        EQU .108
ESPACE      EQU .36
CSPACE      EQU .108
WSPACE      EQU .252
CWSPEED     EQU .192
DOTCNT0     EQU H'000A'
DOTCNT1     EQU H'000B'

CWOUT       EQU GP0
  
  ;; -------------------------------------
  ;; OFFSET
  org	      0

  ;; -------------------------------------
  ;; INIT
init
  bcf       CMCON0,CMPON
  movlw     b'11110110'
  option
  movlw     b'11111110'
  tris	    GPIO
  bcf       GPIO,CWOUT
  clrf      TMR0
  movlw     BEACON_INT
  movwf     SECCNT
  goto      main

  ;; -------------------------------------
  ;; SUBROUTINES
dottime
  movwf     DOTCNT1
dot_outer   
  movlw     CWSPEED
  movwf     DOTCNT0
dot_inner
  nop
  nop
  nop
  nop
  decfsz    DOTCNT0,f
  goto      dot_inner
  decfsz    DOTCNT1,f
  goto      dot_outer
  return
  
send_beacon
  ;; test send out:
  ;; .- .  -
  bsf       GPIO,CWOUT
  movlw     DOT
  call      dottime
  bcf       GPIO,CWOUT

  movlw     ESPACE
  call      dottime

  bsf       GPIO,CWOUT
  movlw     DASH
  call      dottime
  bcf       GPIO,CWOUT

  movlw     CSPACE
  call      dottime

  bsf       GPIO,CWOUT
  movlw     DOT
  call      dottime
  bcf       GPIO,CWOUT

  movlw     WSPACE
  call      dottime

  bsf       GPIO,CWOUT
  movlw     DASH
  call      dottime
  bcf       GPIO,CWOUT

  return
  
  ;; -------------------------------------
  ;; MAINLOOP
main
  movf      TMR0,w
  btfss     STATUS,Z
  goto      main

  ;; this gets called every second
  decfsz    SECCNT,f
  goto      waitfor0
  movlw     BEACON_INT
  movwf     SECCNT

  ;; this gets called every BEACON_INT seconds
  call      send_beacon
  
  ;; is the timer above zero?
waitfor0
  movf      TMR0,w
  btfsc     STATUS,Z
  goto      waitfor0

  goto	    main

  ;; -------------------------------------
  ;; END
  end