I am trying to use a Ardunio to control the power of a LCD TV (simple right?). To do this I cut the wire leading from the power button to the built in circuit board and put my Ardunio in-between. I connect the wire from the button to a analog port and read the signal I get from it. But the problem comes in that all I read is static! The board wont read the voltage coming from the button, I know that the button is sending a constant stream that is interrupted momentarily only when it is pushed down (which is how it is turned on and off).
What would you suggest I do to solve the analog read problem?
I am trying to use a Ardunio to control the power of a LCD TV (simple right?).
Wrong, it appears you don't qualified to modify / repair complex electronics devices, and it'd better if you stop doing so before you burn down a house.
Actually when I first started it was very simple, but then it just stopped working.
Do you think it is a problem with grounding differences between my computer and the TV?
(PS: I will get a fire extinguisher just for you)
That sounds dangerous...
Why not use an IR emitter/receiver and Ken Shirriffs IRRemote library? You can "record" any button press from your remote and send it via IR. If you have no remote the codes are probably available online. Much safer!
Without going in depth of how a SMPS and Standby Voltage works on an LCD,Plasma, TV works.
On the main Switch Mode Power Supply board (PSU) there is a small dedicated section on the board (Stand By Voltage) that supply's 3 to 5 volts depending on make and model to the power button .
When pressed ( If all is working properly ) it triggers the start up of the main part of the SMPS.
The voltage is low on the standby but, on the hot side of the SMPS the primary filter CAPS can have 350 Volts each . So if you do not have proper training you can get hurt .
Just trying to help you be safe.