Your looking for a 12 bit (11bits actually) A-D.
Then some bit manipulation. (Math).

Andre Abelian wrote:

>Rolf,
>
>thanks for your replay. Using Vref is very good idea but in my case the 
>situation is lot more
>complicated. This is how it should be:
>
>0-2,4v  output 0-1023 with 2's complement format and enable a bit
>2.6-5.0v  output 0-1023 disable the bit. While it is in between 2,5v 
>should output 0
>
>any idea?
>
>thanks for your help
>
>Andre
>
>  
>
>>Andre Abelian wrote:
>> 
>>
>>    
>>
>>>Hi to all,
>>>
>>>I need to convert ADC 0-2,5v  result to  0-1023 output to uart.
>>>I am kind of lost how to do this should I add result x 2?
>>>any help will appreciate.
>>>
>>>thanks
>>>
>>>Andre
>>> 
>>>   
>>>
>>>      
>>>
>>You need to get 2.5V on the Vref+ pin, and use that for the 10bit 
>>conversion. The challenge is then to get a 2.5V reference.... ;-)
>>
>>On PIC18 devices see the ADCON1 register bits VCFG0 and VCFG1
>>
>>on PIC16's see the ADCON1 register's PCFG bits.
>>
>>Rolf
>> 
>>
>>    
>>
>
>  
>

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  |  __O    Thomas C. Sefranek   WA1RHP@ARRL.net
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