'**********************************************************************************
'                         Gallerydrive - Zone Control Unit
'**********************************************************************************
'
' pd0:............green lamp
' pd1:............red lamp
' pd2:............Status LED
' pb1(oc1a):......IR transmitting diode LD274
' pc5(adc5):......laser barrier input
' pc4(adc4):......from next zone / last laser barrier
' pc3:............to previous zone
'
' pc0:............"test"-switch
' pc1(adc1):......poti adjust laser
' pc2(adc2):......poti adjust next zone / laser
'**********************************************************************************

$regfile = "m8def.dat"
$crystal = 16000000

Ddrd = &B00000111                                           'relais at pd1 - status led at pd2
Ddrb = &B00000010                                           'IR diode at pb1
Ddrc = &B00001000                                           'signal out to prev. zone at pc3
Portd = &B11111111

Portb = &B11111101
Portc = &B11000111

Config Adc = Single , Prescaler = Auto
Start Adc

Dim I As Word
Dim Test As Bit
Dim Prev_test As Bit

Dim Laser_adjust As Word                                    'potivalue laser adjust
Dim Next_adjust As Word                                     'potivalue next adjust
Dim Laser_in As Word                                        'control voltage coming from laser
Dim Next_in As Word                                         'control voltage coming from next zone
Dim Zone_occupied As Byte
Dim Signal As Byte
Dim Enter_zone As Bit
Dim Exit_zone As Bit
Dim Prev_enter_zone As Bit
Dim Prev_exit_zone As Bit
'------------------------------------------------------------------------------------------------------
'------------------------------------------------------------------------------------------------------
'------------------------------------------------------------------------------------------------------
Signal = 2                                                  '  <-Fill in correct number of Signal here!
'------------------------------------------------------------------------------------------------------
'------------------------------------------------------------------------------------------------------
'------------------------------------------------------------------------------------------------------

Portd.2 = 1                                                 'turn on status led

Readeeprom Zone_occupied , 0
If Zone_occupied = 1 Then
   Portd.1 = 1 : Portd.0 = 0
Else
   Portd.1 = 0 : Portd.0 = 1
End If

Enter_zone = 0
Prev_enter_zone = 0
Exit_zone = 0
Prev_exit_zone = 0
Test = 0
Prev_test = 0

Do

I = I + 1
If I = 400 Then I = 0

Prev_test = Test

If Pinc.0 = 0 Then Test = 1 Else Test = 0                   'read test switch

If Test = 0 And Prev_test = 1 Then                          'switch traffic lights if testmode was currently switched off
Readeeprom Zone_occupied , 0
   If Zone_occupied = 1 Then
      Portd.1 = 1 : Portd.0 = 0
   Else
      Portd.1 = 0 : Portd.0 = 1
   End If
End If

If Test = 1 Then
      If I = 0 Then
         Portd.2 = Not Portd.2                              'status led blinks during test mode
         Portc.3 = Not Portc.3                              'signal output to previous zone switches
      End If
   Else
      Portd.2 = 1
End If


Laser_adjust = Getadc(1)
Next_adjust = Getadc(2)
Laser_in = Getadc(5)
Next_in = Getadc(4)

If Test = 1 Then                                            'testmode:
   If Laser_in > Laser_adjust Then Portd.1 = 1 Else Portd.1 = 0       'retroreflecting mat. detected - red light on
   If Next_in > Next_adjust Then Portd.0 = 1 Else Portd.0 = 0       'retroreflecting mat. detected - green light on
Else
                                                               'normal mode
   Prev_enter_zone = Enter_zone
   Prev_exit_zone = Exit_zone

   If Laser_in > Laser_adjust Then Enter_zone = 1 Else Enter_zone = 0       'compare laser barriers with adjustet values
   If Next_in > Next_adjust Then Exit_zone = 1 Else Exit_zone = 0

   If Enter_zone = 0 And Prev_enter_zone = 1 Then           'car entered zone
      Zone_occupied = 1
      Writeeeprom Zone_occupied , 0
      Portd.1 = 1 : Portd.0 = 0                             'switch traffic light to red
      Portc.3 = 1 : Wait 1 : Portc.3 = 0                    'send flange to previous zone
   End If

   If Exit_zone = 0 And Prev_exit_zone = 1 Then             'car left zone
      Zone_occupied = 0
      Writeeeprom Zone_occupied , 0
      Portd.1 = 0 : Portd.0 = 1                             'switch traffic light to green
   End If

   If Zone_occupied = 0 Then
      Rc5send 0 , 6 , Signal                                'send go signal
   End If


End If


Loop

End