Getting a controller for resistive touch screen?

[fafler]

Hi. I have a wallmounted PC with a resistive touch screen. I want to put a laptop motherboard inside to replace the slow 600 mhz celeron is has now. The screen is standard LVDS and easy to connect to the new board, but the controller for the touch screen is on the old board, so I need another one. The ones I can find on eBay has 4 wires, but I have 5 coming from the glass plate. It doesn't seem to contain any active parts, but it's glued to a plastic frame so I really don't know what's going on bolow.

So, what could the extra wire be for? Can I just buy a controller and try out combinations until it works? Measure the wires to figure it out?

 

[(*steve*)]

The only controllers I've seen in recent memory were usb devices. I cant remember how many connections there were to the sensor itself and I also imagine that the controller needs to match the sensor

 

[fafler]

The controllers I've found have 4 connections to the touch panel and USB in the other end. They doesn't specify exactly what screens they support, so I suppose they are pretty standardized, as they need to be calibrated anyway. Looking at this https://www.sparkfun.com/datasheets/LCD/HOW DOES IT WORK.pdf it seems to be pretty simple to figure out with a ohm meter, so that's what I'm gonna try.

 

[(*steve*)]

The additional connection might be a shield, and maybe you can spot the odd man out to eliminate it. The order for the others may involve a little trial and error.

I'm not certain, but I don't think you can hurt anything by connecting the sensor up incorrectly.