RPi 7" Touch Screen - it's alive!

I've been living with the rather lashed up setup of the RPi and IQAudio DAC, albeit in a nice shiny black box, in conjunction with the Linkwitz LXMinis and accompanying miniDSP 2x4 for maybe six months now. The main drawbacks, if there are any, are

• Wife finds it impossible to use, because she hasn't really got a handle on using a browser or the Kazoo app to select music to play, and really she'd like to have the facility for putting on a CD, as we once could :-o
• Turning off the music at source without having the phone or laptop to hand whilst walking through the stereo listening room is a pain - yeah, bit of a 1st world problem, but Lumin, Kazoo etc are relatively slow to get their act together
• Whilst connecting the CD player (which has an analogue output only, and 5 pin DIN at that, bloody Naim with their silly ideas about hifi) is possible, it currently involves unplugging the RPi from the miniDSP and plugging the CD player into it instead. Boring.

It would be nice (as well as interesting :-) ) to have a handy interface with the renderer. So why not a nice RPi Official © RPi Inc 7" Touch Screen Display? Coming right up, sir...

Bought from thepihut.com, along with a nifty black plexiglass stand, for about £65 (ouch, but hey...), arrived in a couple of days. 

The screen is chunky, heavy, black bezel. It has a PCB with the serial-parallel electronics bolted on the back. You have to attach the RPi to it with the usual threaded standoffs, and then there's the option of powering it all by

1. Connecting USB supply to the screen, and linking power to the RPi with a short USB-USB Micro cable
2. Connecting USB supply to the RPi, and using the supplied patch-type cables to connect RPi GPIO 5.5v/Gnd to screen 5.5v/Gnd inputs

Looks like using a hat DAC prevents option 2, because the DAC uses the GPIO pins...

Screen standing with stand :-) - cool!

The screen and stand are easily assembled, once you take the attached PCB off the screen! The stand is multi-layer plexiglass, and one layer is a bit tricky to get the right way round, but there's only two ways to put it so...

I struggled a bit with the flat ribbon cable to connect the RPi display connector to the screen connector, but I find that with all these flat cable connectors - it's hard to see which side of the connecter the cable goes in!

Rear of screen and stand - note re-attached PCB

I removed the SPDIF interface board from my sample RPi3 and attached it, using the GPIO pin power connections. A quick power up - screen on, RPi on, BUT... the screen was just showing varicoloured vertical lines. Yuck. Power off, retry connection to RPi, power up, and hooray! This time the screen worked, and ended up showing a terminal prompt. Lovely...

Rear view showing attached/connected RPi

I then used a browser on my laptop to point to the Rune instance on the RPi (which was running a previously set up image...) and configured "Start a browser on HDMI/TFT" in the Settings. Restart... and...

Screen showing Rune browser interface!

Result!!

A quick test of the touch capabilities - all the screen touch points and selections work fine, as defined by the browser page. The lower ones are a tiny bit tricky to hit, but it's easy to adjust one's touch point :-). Fantastic, and ridiculously easy. Maybe I should have tried something harder, like integrating a cheap display...