ADC problem in pic16f877 with inputs at both pins

[sush]

adc problem in pic16f877

hi frndz
m working on adc of pic16f877. m using two analog inputs .

when i give inputs at both the pins i.e (either 5 volts to both or ground to both)then the value comes correct but if i give input to one of the pin as 5 volts and other as ground then the adc shows absurd value.

the one on which i give 5 volts shows me 348 decimal and the other one shows 0 .

please help me how can i make it correct

 

[waseem]

Re: adc problem in pic16f877

Hi!
Which pins are u using as inputs and how u have set the refrence to the ADC.
i.e is it using external or internal reference.

Also if u are using two adc channels then u have to aquire each channel independently for conversion.

Also be careful about the aqusition time for each channel.

If u still have problems then post ur code so that we can sort it out for u.

Best of luck.
Regards.