symmetric power supply pic 16f877a

[josepic]

attached in .zip format the simulation in proteus. to visualize the simulation of the symmetric source

[richard]

zip files from a unvetted source , no thanks

a screen shot or a simple description of how A2 is derived and an explanation of how that voltage is to be displayed would help

its a simple thing.
you have two voltages A1 and A2 to be read by adc , that reading needs to scaled to display a value representing the supply outputs
A1 and A2 obviously must have a fixed linear relationships to those outputs to get meaningful results.

a 16f886 can do it just as well as a 16f877a can
if you want more than 1 dp resolution you need to employ some oversampling
to get a stable reading some low pass filtering is required , analog or digital or both