Our project involves making a security system supposedly to be turned on and off by a potentiometer but the wire thats usually connected to analog input is connected to LCD 6 x 12 which seems to be the only thing being controlled by the potentiometer. (parts used are potentiometer, pir, led, LCD6x12, piezo)
The proverbial crystal ball is still in the dishwasher...
➜ Please do yourself a favor and read How to get the best out of this forum. Post accordingly, including code with code tags, necessary documentation for your request such as your exact circuit and power supply details, links to components, etc.
5 Likes
If it's A4 or A5 on an Uno, reserved for I2C, then use any other analog input for the pot.
The potentiometer isnt connected to any analog its connected to contrast(v0) in the LCD
connect it as well to A0
You need a second pot connected to an analog input , you can’t use the display one
I suggest you post an annotated schematic showing all parts such as modules, resistors, caps, etc. Be sure to show how it is wired include all connections, power, ground, power sources. etc. If you want this go go faster read the Arduino Cookbook.
and find out the range obtainable from A0.
I wonder why the display backlight could be useful for controlling anything else.
Hi, @maymelody
Welcome to the forum.
Can you please post a copy of your circuit, a picture of a hand drawn circuit in jpg, png?
Hand drawn and photographed is perfectly acceptable.
Please include ALL hardware, power supplies, component names and pin labels.
Why do you want to use a potentiometer to turn ON and OFF your project?
Why the LCD contrast potentiometer?
Thanks.. Tom... 
Did you consider using a potentiometer that has a switch mounted on the back? The switch could turn the power for your project on and off!
This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.