I have just purchased a “low cost” 7" touchscreen here: Écran LCD D 7 pouces, 1024x600, avec support h, angle de vision complet à 178 degrés, pour raspberry PI 3B + 4B | AliExpress
It did not work out of the box, I hade to modify the resolution parameters to have it work.
Here is finally what I used, in file /boot/userconfig.txt:
The screen is given for 1024x600, but unfortunately, the “standard” configuration for this resolution did not work:
hdmi_cvt = 1024 600 60 6
hdmi_group = 2
hdmi_mode = 87
hdmi_drive = 2
This configuration made the screen blink. I don’t know why.
Anyway, the one I chose is nice, given the size of the screen. It is equivalent to 848x480, which is nice pour Volumio WebUI on this 7" screen.
I found all relevant information for hdmi configuration here: Video options in config.txt - Raspberry Pi Documentation
I tested the screen on RPI3 and RPI4. I found it a good value for money. It comes with a set of adapters for HDMI and USB Touch for both RPIs, and a simple but very useful stand.
If this can help.
this should be the settings for your 7inch touch display type H
hdmi_cvt 1024 600 60 6 0 0 0
you could find it here 7inch HDMI Display (H) - LCD wiki
don’t forget to plugin the usb for your touch.
Thanks for the hint. It works fine, I guess there was something missing in my configuration when I tried this resolution. I’m not at all any HDMI guru, I guess!
Nevertheless, after trying both resolutions, I will stay on my lower one, I find it more suitable for this size of screen (i.e the left column does not show but is not really useful when just playing music), it is enough to have the cover of the CD, volume, time of the track, plus the “standard” commands).
A hint: I use a RPI4 with its genuine power supply, attached to a Maxtor USB3 4To disk, which is powered by the RPI. In this situation, it is needed to have an external supply for the screen, otherwise, the disk won’t start correctly and won’t mount. But without this USB disk, the screen can be powered though the USB touch plug, which is fine.
usb powered disk are not bootable because of to mutch current pulling always power dacs and
hdd on it’s own power and not from the pi…
I don’t boot on the USB disk, it just holds my music library.
pi just doesn’t have the power to power any big device so hubs disks and dacs need there own power
you only have 0,5 amp max on your usb most of the things pull more amps…
Well, my USB disk (2,5", 4To) alone is powered by the RPI without any problem. My DAC is external, and has its own supply. But the screen must also have its own power supply.
But if my music was on a NAS, it would be enough to have this screen aslo powered by the RPI. I don’t like to add power supplies when not needed, most of them are noisy, and low noise supplies are expensive…