' Name        : VUX20.pbp
' Compiler    : PICBASIC PRO Compiler 2.6
' Assembler   : PM or MPASM
' Target PIC  : PIC16F690 or similar type compatible with LAB-X20 board
' Hardware    : LAB-X20 Experimenter Board
' Oscillator  : 4MHz external crystal
' Keywords    : ADCIN, PWM
' Description : PICBASIC PRO program to display pot on 2 segment bargraph.
' The last LED in the graph dims or brightens with changes in the pot.
'

potval   Var Byte   ' Pot result variable
i        Var Byte   ' For-loop variable
position Var Byte   ' LED position variable
bright   Var Byte   ' Brightness variable

   ANSEL = %00000100        ' Set PORTA.2 analog, rest digital
   ANSELH = %00000000

mainloop:
   Adcin 2, potval          ' Read Pot on PORTA.2
        
   position = potval / 127  ' Position of last lit LED
   bright = (potval // 127) * 2 ' Brightness of last lit LED

   For i = 0 To 1           ' Set each LED
     If i < position Then
        High i + 4          ' Turn on if lower than last lit LED 
     Else
        Low i + 4           ' Turn off if higher than last lit
     Endif
   Next i
   Pwm position + 4, bright, 5  ' Dim the last LED
   Goto mainloop                ' Do it forever

   End