12 bit A2D on 18F46K80, need a bit of help for figuring TAD and getting correct value

[mark_s]

Here are some snippets of code from a project of mine using a PIC18F45K80. I think you should remove this section from your code. When not using adcin, I prefer to manually set the adc registers.

 '----------------------------------------------------------------------------------------
 'Define the Analog to Digital conversions
 DEFINE ADC_BITS 12 '12-bit resolution
 ' DEFINE ADC_CLOCK 5 'Set clock source to Frc/16
 DEFINE ADC_CLOCK 6 'FOSC/64, 0.8uS @ 64Mhz
 DEFINE ADC_SAMPLEUS 50 'Sample time in uS before A/D conversion is started

 '-----------------------------------------------------------------------------------------

Maybe something here will help you get it running.

'ADC-----------------------------------------------------		    
ADCON0 = %00000001 ' A/D module enabled
ADCON1 = %01110000 '%01110000 Vref = INT 4096, TRIG ctmu, NEG REF VSS
ADCON2 = %10010100 ' Right justified, 12 Tad, Frc clock
ANCON1 = %00000000  'Select Digital or Analog AN8 - AN14

'-------------------------------------------------------------
TRISA = %00000011

ADC_AN0   var word
ADC_AN1   var word


'=======================================================================
GET_AD0:
ADCON0 = %00000001      'AN0 ENABLED
           ADCON0.1 = 1
@   nop 
@   nop
@   nop 
@   nop
@   nop 
@   nop
@   nop 
@   nop           
    WHILE ADCON0.1 = 1       ' A/D complete?
@   nop 
@   nop     
    WEND
ADC_AN0.lowbyte =ADRESL
ADC_AN0.highbyte = ADRESH
'===================================================================
GET_AD1:
ADCON0 = %00000101      'AN1 ENABLED
           ADCON0.1 = 1
@   nop 
@   nop
@   nop 
@   nop
@   nop 
@   nop
@   nop 
@   nop           
    WHILE ADCON0.1 = 1       ' A/D complete?
@   nop 
@   nop     
    WEND
ADC_AN1.lowbyte =ADRESL
ADC_AN1.highbyte = ADRESH   

'===================================================================