Using a touchscreen with the Pi


4 posts
by caesarsgrunt » Mon Jun 18, 2012 6:18 am
I am interested in using a Pi as the basis of a simple music player - iPod style. The device will probably be permanently mounted inside my boat (tethered to the audio in of a car stereo).

I am not (yet!) familiar with many of the the hardware and software issues involved (which is the main reason I want to do this; as it will make a great learning project for me), so I wondered if anyone could give me some tips.

Ideally the device would consist of the Pi and a 4" (or thereabouts) touchscreen.
However, in my touchscreen researches I keep hitting a brick wall: I can't work out how the touchscreen should be interfaced to the Pi.

Presumably the display itself would connect to either the HDMI or the RCA connector, though none of the screens I've come across mention this. But how would the touch sensor connect? All the ones I've seen seem to have ribbon connectors - mostly for both the display and the touch sensor.
Resistive touchscreen overlays seem to normally have four wires - but where should these four wires be connected????

This device, for example, seems to have a 40-pin parallel connector... I can't see any way that could be connected to the Pi; could it?

If anyone could give me any tips that would be fantastic.

Equally, if anyone can point me to a source for a reasonably-priced touchscreen in the 3.5" to 5" range, I'd be very grateful, as I've been having trouble finding them. Ideally capacitive would be nice, but I don't know what pricing would be like. Resistive isn't a dealbreaker.

Thanks in advance!
Posts: 1
Joined: Mon Jun 18, 2012 3:50 am
by daveb237 » Mon Jun 18, 2012 8:39 am
Hi,
I can see 2 ways this might go:
1. Here's a LCD/touch panel, about the same price as the Pi itself:
http://iteadstudio.com/store/index.php? ... cts_id=541
It might connect to the GPIO lines on the Pi, with a cheap ADC to do the touch panel. (That board is apparently aimed at the Arduino).
2. There's a display connector in the middle of the Pi board, running the "Display Serial Interface" standard, which apparently is proprietary (you have to join the standards body to get a copy). Maybe someone knows of a ready-made panel supporting this standard. I suspect this is the quicker way to go, as (hopefully) the existing display drivers can handle it with minimal changes.
Regards
Posts: 1
Joined: Mon Jun 18, 2012 8:32 am
by Chimaera654 » Fri Jul 20, 2012 5:50 pm
Posts: 1
Joined: Fri Jul 20, 2012 5:48 pm
by juanRIOT » Sun Jul 29, 2012 12:46 pm
There's a thread currently tackling this specific project. Hope this helps.

http://www.raspberrypi.org/phpBB3/viewtopic.php?f=64&t=8983

Hope this helps.
Posts: 21
Joined: Fri Aug 26, 2011 12:17 pm