LCD BARgraphs

[ChrisMicro]

Can I pick someone's brain please?
I'm at the moment trying to make an auto switchover gadget to change from running on Diesel to Veg Oil once certain temperatures have been reached, and to try and work this out I'm using the easypic5 development board.
So far: I have a 16f877A programmed so it will switch certain outputs when certain inputs go high all and well
It even displays what it's doing on the LCD display

What I'd like to incorporate if its possible is this? or a variation of it the Bargraph but use it as a fuel level sensor, i.e. changing position depending on the level of the fuel in the tank (variable resistor)

Does anyone know any code that will do that or give me a starting place to play with?
I know I've got 2 A/D converter inputs on the developement board I can play with that have a 10K pot connected and are configured so I can change the input on either of the RA0, RA1, RA2, RA3, RA4, or RA5 pins and measure the voltage on them ( unfortunatly I'm only just learning about Pic's at the moment and know nothing about A/D and how to use it, I am learning by trying and experimenting But I am a quick learner), so IF anyone has any code they could share with me to show me how to get started with this I'd be grateful Thanks

Here is my code for monitoring the sensors in a car. Note: this method is more accurate than ADCIN

'****************************************************************
'*  Name    : CarMonitor.PBP                                     *
'*  Author  : Chris Bezuidenhout                                *
'*  Notice  : Copyright (c) 2007 Micro Developments             *
'*          : All Rights Reserved                               *
'*  Date    : 2007/10/23                                        *
'*  Version : 1.1.1                                             *
'*  URL      :http://www.patenttrade.net                             *
'*          :                                                   *
'****************************************************************
INCLUDE "Modedefs.Bas"

       OSCCON = %01100000                  'set the intrc osc change bit 4 to logic  1 for 8 MHz
       OSCTUNE = %000000
       
DEFINE 	OSC		4     ' Set IRC Frequency
DEFINE ADC_BITS 10       ' Set number of bits in result
DEFINE ADC_CLOCK 1    ' Set clock source (rc = 3)
DEFINE ADC_SAMPLEUS 50 ' Set sampling time in microseconds
          
IgnIn    var     word
Altin    var     word
Oilin    var     word
TempIn   var     word
ResIn    var     word               'Reserve input
IgnOut   var     portb.0
AltOut   var     portb.1
OilOut   var     portb.2
TempOut  var     portb.3
Buzzer   var     portb.4
ComO     var     portb.5
SigOut   var     portb.6
sp2      var     portb.7
Spin1    var     porta.6
Spin2    var     porta.7
X        var     byte
Y        var     byte


TRISA = %11111111          'Porta 0-4 all analog 5 input only pull high
TRISB = %00000000
ADCON0 = %11000001
Pause 2000 ' Wait .5 second 
ADCON1 = %10000010 ' Set PORTA analog and RIGHT justify result



OPTION_REG = $7f        ' Enable PORTB pullups

pause 500
portb = 0
low Buzzer
     
       
       
Main:       
       gosub CIgn
       gosub CAlt
       gosub COil
       gosub CTemp
       gosub Send
       
       
Ignition:
       if ignin = 0 then 
       high Ignout
       gosub Send
       goto main
       endif
       if ignin > 300 then 
       low ignout
       goto Alternator
       endif
'       if ignin > 0 and ignin < 300 then
       for y = 1 to 3
       gosub CIgn
       gosub Send
       if ignin > 300 then  Alternator
       
       for x = 1 to 2
       high Ignout
       high buzzer
       pause 200
       low buzzer
       pause 200
       next x
       pause 1000
       next y    
       
'       endif
Alternator:
           if ignin = 0 then goto main
       low ignout       
       if Altin > 1020 then 
       high altout  '?????????Kalibreer
       for y = 1 to 3
       gosub CAlt
       gosub Send
       if altin < 1020 then Oil
       for x = 1 to 4
       high buzzer
       pause 200
       low buzzer 
       pause 200
       next x
       pause 1000
       next y
       endif
        
Oil:   
       if ignin = 0 then goto main
       low altout           
       if Oilin > 10 then    'This variable have to be calibrated to sensor unit
       high Oilout           'for a plain on/of it must be set to 0, the pot at minimum 
       for y = 1 to 3        'if there is some contact resistance it can be calibrated acordingly
       gosub COil            'For a analog (resistive) sensor it have to be calibrated to 
       gosub Send            'the sensor
       if oilin < 10 then Temperature    'So is this one
       for x = 1 to 6
       high buzzer
       pause 200
       low buzzer
       pause 200      
       next x
       pause 1000
       next y
       endif
       
Temperature:
            if ignin = 0 then goto main
       low Oilout
       if tempin < 85 then 
       high tempout
       for y = 1 to 3
       gosub CTemp
       gosub Send
       if tempin > 85 then main
       for x = 1 to 8
       high buzzer
       pause 200
       low buzzer
       pause 200 
       next x
       pause 1000  
       next y
       endif
       low tempout
   goto main         
CIgn:
       ADCON0 = %11000101             'start ADC  A0
       gosub notdone
       IgnIn.highbyte = ADRESH
       IgnIn.Lowbyte = ADRESL
       write 0,ignin.highbyte
       write 1,ignin.lowbyte
       return
CAlt:       
       ADCON0 = %11001101             'start ADC A1
       gosub notdone
       altin.highbyte = ADRESH
       altin.Lowbyte = ADRESL
       write 2,Altin.highbyte
       write 3,Altin.lowbyte
       return
COil:       
       ADCON0 = %11010101             'start ADC A2
       gosub notdone
       oilin.highbyte = ADRESH
       oilin.Lowbyte = ADRESL
       write 4,oilin.highbyte
       write 5,oilin.lowbyte
       return
CTemp:       
       ADCON0 = %11011101             'start ADC A3
       gosub notdone
       TempIn.highbyte = ADRESH
       TempIn.Lowbyte = ADRESL
       write 6,tempin.highbyte
       write 7,tempin.lowbyte
       return
CRes:       
       ADCON0 = %11100101             'start ADC A4
       gosub notdone
       resin.highbyte = ADRESH
       resin.Lowbyte = ADRESL
       Return        
Send:
       serout SigOut, N2400,["A",IgnIn.highbyte,IgnIn.lowbyte,altin.highbyte,altin.lowbyte,Oilin.highbyte,Oilin.lowbyte,Tempin.highbyte,Tempin.lowbyte,resin.highbyte,resin.lowbyte]
       return
notdone: Pause 5 
       If ADCON0.2 = 1 Then notdone' Wait for low on bit-2 of ADCON0, conversion finished 
       return
end