#URGENT. problem with c code for calibrating lcd based dvm

Thread Starter


Joined Apr 24, 2014

View attachment lcd.txt

View attachment voltmeter.txt

hello friends, attached with this thread are the circuit diagram and the c codes for LCD based digitalvoltmeter.

It is working perfectly in PROTEUS.
My problem is that i want to calibrate it i.e. if the input voltage is1v, instead of showing 1v in the LCD op i want to scale it and show 1V*some constant (say 500) and display it. So, the new o/p in the lcd now is 500v. Can any1 please mention the changes in the c code to be done in order to achieve this. I hope you get the problem. I am a novice in C language and i reallyneed your help. It is a little Urgent. You can message me for any doubts.


Joined Feb 19, 2010
Do the calculations in the uC, then show whatever you want on the lcd.

Lets say:
1. You read 1 volt, store it in variable: A=1
2. Do the scaling, either reuse A or use different variable: A=A*500 or B=A*500
A now contains 500, or, if you used different variable, B contains 500.
3. Write the variable to lcd, then write letter V or word volts to lcd. Now your lcd shows: 500 V or 500 volts.


Joined Oct 29, 2009
Maybe you should first explain why your issue is more urgent than anyone else's?

I have read your post 5 times and I still don't understand it.

What is an op???

Best I can figure is you just need to multiply by 500 and display that value.