' Name        : CALLIDXT.pbp
' Compiler    : PICBASIC PRO Compiler 2.6
' Assembler   : PM or MPASM
' Target PIC  : PIC16F877-20
' Hardware    : LAB-XT Experimenter Board
' Oscillator  : 20MHz external
' Keywords    : LCDOUT, SELECT CASE
' Description : PICBASIC PRO program to display Caller ID information
' on LCD.  Connect either jack on the LAB-XT to a telephone line.
' Caller ID service must be provided by your local phone company.
' This code only reads Multiple Data Message Format. 
' LED4 lights when ring is present.
'

Define LOADER_USED 1    ' Only required for melabs Loader

Define OSC 20           ' Match the crystal on the board

' 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

ring_detect     Var PORTA.2     ' Define the ring-detect input pin
cid_serial_data Var PORTA.0     ' Define the Caller-ID serial input pin
led4            Var PORTC.1     ' Define LED output
idstring        Var BYTE[96]    ' Array variable for recording the CID data
h               Var Byte        ' Variable for loop count and timing
i               Var Byte        ' Variable for loop count
length          Var Byte        ' Variable stores the length of CID data string

   ADCON1 = 7                   ' Set PORTA and PORTE to digital
   Pause 200                    ' Wait for LCD to start up

   LCDOut $fe,1, "Caller ID for LAB-XT" ' Vanity display

mainloop:
   IF ring_detect = 1 Then mainloop     ' Wait here until ring detected
   High led4                            ' Light LED to indicate incoming ring

time_after:     
   IF ring_detect = 0 Then i = 0        ' Clear timer variable if still ringing
   i = i + 1                            ' Increment timer variable
   Pause 1                              ' Pause 1mS
   IF i < 250 Then time_after           ' Loop here until 250mS after ring stops       
   Low led4                             ' Ring finished, kill LED

   ' Look for CID data, abort if no data for 500mS
   SerIn2 cid_serial_data, 813, 500, mainloop, [wait($80),length,STR idstring\length] 

   LCDOut $fe,1                         ' Clear the display
   For i = 0 TO length                  ' Begin loop, each count represents a character
                                        ' in the recorded CID data string.

     Select Case idstring[i]            ' For each character, check for known parameter types
     Case $01                           ' Parameter type 01 (hex) is date and time.
             i = i + 1                  ' Move index pointer to parameter length character.
                                        ' This avoids the length character being mistaken for
                                        ' a parameter-type code.

             LCDOut $fe,$80,idstring[i+1],idstring[i+2],_ ' Display date and time
             $FE,$C0, idstring[i+3],idstring[i+4], " ",_
             $FE,$83, idstring[i+5],idstring[i+6],":",_
             idstring[i+7],idstring[i+8]
                                
     Case $02, $04                       ' Parameter type 02 is the phone number.
                                         ' Parameter type 04 is the reason, if there is no number
              LCDOut $FE,$89             ' Move the LCD cursor to position 9 on line 1
              GoSub disp_string          ' Display the number string

     Case $07, $08                       ' Parameter type 07 is the caller's name.
                                         ' Parameter type 08 is the reason, if there is no name
              LCDOut $FE,$C3             ' Move the LCD cursor to position 4, line 2
              GoSub disp_string          ' Display the name string
      End Select
   Next i                                ' Loop to the next character in the array
   GoTo mainloop                         ' Return and wait for next ring
        
' Subroutine to display text string. This routine is called when a variable length CID parameter
' type is read from the array. The number of characters to display is stored in the next array
' location after the parameter type.

disp_string:                                    
   i = i + 1                              ' Move the index pointer to the parameter-length byte
   IF idstring[i]=1 Then                  ' If the parameter is only 1 character long, then display a reason
      IF idstring[i+1] = "O" Then LCDOut "Out Of Area" ' "O" is Out Of Area
      IF idstring[i+1] = "P" Then LCDOut "Blocked"     ' "P" is Private Caller
   Else                                   ' If the parameter is longer than 1 character
      For h = 1 TO idstring[i]            ' Loop from 1 to the length of the parameter
        LCDOut idstring[i+h]              ' Display each character in the parameter
      Next h                              ' Do it for the next character
   EndIF
   Return

   End