input device question

Does anyone know how “touchpad” devices input information onto a computer monitor? I understand how the actual touchpad functions but am a bit confuses as to how it relays information to the monitor? Is it software? if so does it need some sort of hard drive (brain) to work?

I am sure I may be corrected by someone who knows more than I do, but I believe the touchpad uses similar if not the same drivers as a mouse. I do know that for touch screens I have specified for different products there was no need for additional software. Just hooked it up to the cpu and it works. I asked once and a software engineer said it runs off the mouse drivers.

thanks iab, but lets say that we wanted to use a touchpad but not on a computer, say a DVD player? Without a cpu how would we be able to do that?

many dvd players run an embedded version of UNIX, Linux, or BeOS so a mouse driver for the appropriate OS should work (though it may require additional software) the only problem is that accessing the OS to load the driver is tough (no keyboard) and there’s nowhere to plug the touchpad in. If your plan is to design a dvd player that uses a touchpad it should be pretty easy to implement for the software engineer that said most dvd menus are just written for simple arrow key movement (4-10 selections per screen) so i don’t see that a touchpad would make things much easier unless there were a lot more selections

One-off solution:
Some “Industrial DVD Players” include mouse support, like this: Pioneer DVD-V7400

…It’s got an older-school PS/2 (no relation to PlayStation) mouse connector. Since many trackpads behave like mice out of the box, if you found the right track pad, you might be good to go!

Mass-Produced Product Solution:
Hire an electrical engineer to source the materials. It’s probably custom, but not necessarily. So much is at the microchip level these days that it might require little more than the right microcontrollers and some minor custom layout.

Thanks guys (and/or girls)