' Name        : BPX.pbp
' Compiler    : PICBASIC PRO Compiler 2.6
' Assembler   : PM or MPASM
' Target PIC  : 40-pin 16F877A, 18F452 or similar
' Hardware    : Lab-X1
' Oscillator  : 4MHz external crystal
' Keywords    : LCDOUT, SERIN, SERIAL LCD
' Description : PICBASIC PRO program to simulate an LCD
' Serial Backpack. Serial data received is displayed on
' the LAB-X1 LCD.
' 

' Define LOADER_USED to allow use of the boot loader.
' This will not affect normal program operation.
Define LOADER_USED 1

' Define LCD registers and bits
Define LCD_DREG  PORTD
Define LCD_DBIT  4
Define LCD_RSREG PORTE
Define LCD_RSBIT 0
Define LCD_EREG  PORTE
Define LCD_EBIT  1

char  Var Byte     ' Storage for serial character
mode  Var Byte     ' Storage for serial mode
rcv   Var PORTC.7  ' Serial receive pin
baud  Var PORTA.0  ' Baud rate pin - 0 = 2400, 1 = 9600
state Var PORTA.1  ' Inverted or true serial data. 1 = true

   ADCON1 = 7            ' Set PORTA and PORTE to digital
   Low PORTE.2           ' LCD R/W line low (W)
   Pause 500             ' Wait for LCD to startup

   mode = 0              ' Set mode

   If (baud == 1) Then
      mode = 2           ' Set baud rate
   Endif

   If (state == 0) Then
       mode = mode + 4   ' Set inverted or true
   Endif

   Lcdout $fe, 1         ' Initialize and clear display

mainloop:
   Serin rcv, mode, char ' Get a char from serial input
   Lcdout char           ' Send char to display
   Goto mainloop         ' Do it all over again

   End