Posted in Keil's forum

I'm about to design an ADC for unipolar inputs(positive and negative)
using an 80C552...
A couple of questions:
We know that Vref=(Vref+ - Vref-)
If Vref+ = 2.5V
and Vref- =-2.5V
Then

Vref=(2.5 - 2.5)=0 OR
Vref=(2.5 - (-2.5))=5 ?

What will be the value of LSB?
Is is still applying the LSB = Vref/1024?

What would be the 10-bit ADC output if Input=0
Thanks for your time
John