ADC Value Fluctuating in PIC Voltmeter and Ammeter LCD PIC16F877A

[musovern]

Hi.
I have just joined this forum looks like a great place.


I have just made this Volt ammeter with the 16F877A.


I am came across the post about ADC Value Fluctuating in PIC Voltmeter and Ammeter LCD PIC16F877A which I have the same problem.

From what i have been reading it's been solved.

I'm just not to sure what "There was wiring mistake and common grounding was missing" ?

Is there anyone could help me with this

Kind regards

Vernon

 

[pjmelect]

The most common reason for the PIC ADC fluctuating is that the voltage reference has been tied to the supply rail and you have noise on the supply rail. A large capacitor on the decoupled VREF should cure. Another cause could be that the input voltage is at to high an impedance (should be less than 10K or that the input voltage is noisy.