$regfile = "m328pdef.dat"
$crystal = 16000000
$hwstack = 64
$swstack = 32
$framesize = 128

'***********************************************
'*                                             *
'*         LCD KEYPAD SHIELD DEMO              *
'*                                             *
'*    RobotDyn Shield with resistive keypad    *
'*                                             *
'*  Demo shows hardware configuration, and     *
'*      function for reading switches          *
'*                                             *
'*                                   by BARTek *
'***********************************************

Config Submode = New

'***********************************************
'*           ALPHANUMERIC LCD                  *
'***********************************************

 Config Lcdpin = Pin , Rs = Portb.0 , E = Portb.1 , Db4 = Portd.4 , Db5 = Portd.5 , Db6 = Portd.6 , Db7 = Portd.7
 Config Lcd = 16x2
 Cursor Off , Noblink : Cls

'***********************************************
'*         CONFIG ADC FOR SWITCHES             *
'***********************************************

 Config Adc = Single , Prescaler = Auto , Reference = Avcc

'***********************************************
'*            TIMER2 FOR TIME BASE             *
'***********************************************

 Config Timer2 = Timer , Prescale = 1024 , Compare_a = Disconnect , Clear_timer = 1
 Compare2a = 155                                            '10ms @16MHz

'***********************************************
'*                VARIABLES                    *
'***********************************************

 Const Sw_r = 1
 Const Sw_u = 2
 Const Sw_d = 3
 Const Sw_l = 4
 Const Sw_s = 5
'switches
  Dim Old_key As Byte , Key_cnt As Byte , Key As Byte
'demo
  Dim Lr As Integer , Up_dn As Integer , Flipb As Byte

Function Read_keypad() As Byte

 'function with autorepeat

 Local Adc_read As Word , Read_key As Byte , Key_val As Byte

   Adc_read = Getadc(0)

   Select Case Adc_read
    Case 0 To 100 : Read_key = Sw_r                         'right = 0
    Case 101 To 250 : Read_key = Sw_u                       'up = 145
    Case 251 To 400 : Read_key = Sw_d                       'dwn = 330
    Case 401 To 600 : Read_key = Sw_l                       'left = 506
    Case 601 To 850 : Read_key = Sw_s                       'select = 743
    Case Is > 851 : Read_key = 0                            'no key = 1023
   End Select

   If Read_key <> 0 Then
    If Old_key = Read_key Then

     If Key_cnt < 20 Then
      Incr Key_cnt
       Key_val = 0
     Else
      Key_cnt = 0
       Key_val = Read_key
     End If

    End If

   Else
    Key_cnt = 15
     Key_val = 0
   End If

   Old_key = Read_key
    Read_keypad = Key_val

End Function

'for demo
Locate 1 , 1 : Lcd "UpDn=0"
Locate 2 , 6 : Lcd "< 0 >"
Locate 1 , 14 : Lcd "*"

Do

 If Tifr2.ocf2a = 1 Then                                    '10ms
   Tifr2.ocf2a = 1

   Key = Read_keypad()

 End If

   If Key <> 0 Then

    Select Case Key
     Case Sw_u
      If Up_dn < 9 Then Incr Up_dn
       Locate 1 , 6 : Lcd Up_dn ; " "
     Case Sw_d
      If Up_dn > -9 Then Decr Up_dn
       Locate 1 , 6 : Lcd Up_dn ; " "
     Case Sw_r
      If Lr < 9 Then Incr Lr
       Locate 2 , 7 : If Lr >= 0 Then Lcd " " : Lcd Lr
     Case Sw_l
      If Lr > -9 Then Decr Lr
       Locate 2 , 7 : If Lr >= 0 Then Lcd " " : Lcd Lr
     Case Sw_s
       Locate 1 , 14
       If Flipb = 0 Then
        Lcd " *" : Flipb = 1
       Else
        Lcd "* " : Flipb = 0
       End If

    End Select

    Key = 0
   End If

Loop
End