' Name        : BPX1934X.pbp
' Compiler    : PICBASIC PRO Compiler 2.6
' Assembler   : MPASM
' Target PIC  : 40-pin 16F1934 or similar
' Hardware    : LAB-X1 Experimenter Board
' Oscillator  : 4MHz external crystal
' Keywords    : LCDOUT, HSERIN
' Description : PICBASIC PRO program to simulate an LCD Serial Backpack.
' Serial data received on the USART is displayed on the LAB-X1 LCD.
' 

' 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

Define HSER_BAUD 9600
Define HSER_CLROERR 1   ' Automatically clear over-run errors
Define HSER_RCSTA 90h	' Enable USART receive
Define HSER_TXSTA 24h	' TXSTA=%00100100. TX enable, BRGH=1 for high-speed

char Var Byte      ' Storage for serial character

   Gosub Init      ' Hardware initialization routine
   
ClrLCD:
   Lcdout $fe, 1   ' Initialize and clear display

Mainloop:
   Hserin [char]   ' Get a char from serial input
   If char="~" Then ClrLCD ' Send the ~ character to clear LCD display
   Lcdout char     ' Send char to display
   Goto Mainloop   ' Do it all over again

Init:
   ANSELA = 0    ' porta all digital
   ANSELB = 0    ' portb all digital
   ANSELD = 0    ' portd all digital
   ANSELE = 0    ' porte all digital
   
   OPTION_REG.7 = 1 ' Disable PORTB pullups
   TRISD = 0        ' PORTD all outputs
   
   Pause 100        ' Wait for LCD to start
   Return           ' Return to caller
   
   End