'{$STAMP BS2}
'{$PBASIC 2.5}
'Altimeter 12 Bit scottalt1_2.bs2
'Version 1.2

' [Declarations]
adcBits     VAR   Word
maxalt      VAR   Word
grndlevel   VAR   Word
maindeploy  VAR   Word
delaybits   VAR   Word
x           VAR   Word
grnd  DATA Word 4095
log DATA Word 4095
mainde DATA Word 4095

' [Initialization]

CS      PIN 0
CLK     PIN 1
DataOutput PIN 2
DEBUG CLS

' [Main Routine]

PAUSE 3000                                         ' Warm up delay

HIGH CS                                            ' Records initial
LOW CS                                             ' ground level
LOW CLK                                            ' altitude.
PULSOUT CLK, 210                                   '
SHIFTIN DataOutput,CLK,MSBPOST,[grndlevel\13]      '
WRITE grnd, Word grndlevel                         '
DEBUG "Start Altitude    ", DEC4 grndlevel         '

DO                                                  'Mach Delay stops
  HIGH CS                                           'readings for set amount
  LOW CS                                            'of time in PAUSE.
  LOW CLK                                           '
  PULSOUT CLK, 210                                  '
  SHIFTIN DataOutput,CLK,MSBPOST,[grndlevel\13]     '
  READ grnd, Word delaybits                         '
  LOOP UNTIL grndlevel +12 < delaybits:  PAUSE 4000 ' +12 keeps altimter from
                                                    ' starting until about 100'.
DO                                              'Starts main loop.
  GOSUB ADC_Data
  GOSUB display
  GOSUB record
  GOSUB deploy
LOOP

' [Subroutines]
ADC_Data:                                     'Gathers data from sensor.
    HIGH CS
    LOW CS
    LOW CLK
    PULSOUT CLK, 210
    SHIFTIN DataOutput,CLK,MSBPOST,[adcBits\13]
    RETURN

Display:                                      'Display on Terminal.
    DEBUG HOME
    DEBUG CR, CR, "Altitude: ", DEC4 adcBits
    RETURN

record:                                       'Record to eeprom.
    READ log, Word maxalt
    DEBUG CR, "max altitude", DEC4 maxalt
    IF adcbits < maxalt THEN WRITE log, Word adcbits
    PAUSE 100
    RETURN

deploy:                                 'Apogee deploy code.
   IF maxalt + 5 < adcbits THEN HIGH 3  'The (+5) adds delay to deployment.
   PAUSE 1500
   LOW 3
   IF maxalt + 5 < adcbits THEN GOTO main
   RETURN
main:                                   'Main deploy code.
   'x = grndlevel - maxalt / 7
   maindeploy = grndlevel - 50
   DEBUG CR, "main deployment", DEC4 maindeploy
   WRITE mainde, Word maindeploy
   IF adcbits > maindeploy THEN HIGH 4
   PAUSE 2000
   LOW 4
   IF adcbits > maindeploy THEN END     'Once main has fired, end.
   RETURN