I already create a topic in RPI forums but because I’m planning to use Volumio for this project also will as here
I’m planning my next diy project for compact active speaker/soundbar with Rpi, dac and Touchscreen.
The speaker will be powered from the mains so there will have at least two power supply units (for an amplifier and for the Rpi).
Until now I have built two audio systems with built in Rpi A and Rpi zero both using I2s dacs.
This time I wish to add some touchscreen for possibility to use Volumio even without wifi access.
I don’t know if is doable but from the information I found on internet I think there is some hope
Rpi Zero W would the the best choice because of its small size.
The problem is that I’m not sure what will be the proper approach to connect the screen and the dac to the Rpi.
I found some topics in which people ask how to connect both touchscreen and I2s dac using GPIO and seems that is not possible.
Not necessarily to use I2s dac but I don’t have an experience with other solutions.
I would be very happy if someone shared experience with such configuration (Pi zero + dac +touchscreen) or similar solution.
This is my touchscreen panel if you want to take a look. I am using the WaveShare 7 inch screen which uses USB input instead of GPIO pins. The touch function like a touchscreen on top of a mouse pointer. It is probably not quite as good as an official RPi screen but it still works well. I can post more pictures if you like. I craft the frame myself but you can buy a case for it too.
I use a RPi 3 because the screen uses X11 and therefore requires more processing power to drive. A RPi zero will make it extremely slow in response. My experience with RPi zero is that it gets unresponsive with Audio Resampling set to Very High so if you add a screen to then it will probably unusable.
The Official Pi screen uses the Pi’s DSI port and touch is via I2C. You will have to modify the pins if you use a HAT DAC. It depends how you want to integrate the whole thing ofc. The HDMI connector on the Waveshare can be a problem because it is bulky. Also be very careful with the micro USB connector as I accidentally broke mine and had to solder it back in. There are different WaveShare models you can check out from their site, also instructions for setting it in portrait mode.
I don’t have an official Pi screen so I don’t know how the touch function feels. The one on the WaveShare actually displays the pointer. It is like when you touch on the screen the pointer move there and press. Which sometimes requires are more positive press on the screen to make sure. The model I use is capacitive, yes.
Micro USB port came off, you may need a touch of solder on the side of the socket to reinforce the port (too much solder may get inside the port so be very careful.
I use a 270 degree HDMI adaptor now or the default cable will stick out like this. Also a 90/270 degree micro USB adaptor.