Page 1 of 1

[Solved] GearBest Screen Doesn't Power On

Posted: Sun Nov 05, 2017 1:23 am
by skorpien
I was trying to test my GearBest screen before starting on my build and I can't seem to get any output whatsoever.

I haven't done the 5V mod yet. I have a 12V Molex power supply and wanted to test with that first.

I connected the video to PP24 on my Pi 3 and the 12V and ground coming from the power supply. I think I have the display connected properly (snug fit in connector), and when I test the 3.3V and ground through holes on the controller board I get a proper reading, meaning the controller board's getting power. I also tested PP24's voltage and I got the same reading on the connector of the controller board

About the only thing I didn't test thoroughly was my Pi's composite out as I don't have any displays that would take composite video.

I'm also using input 1 on the display (white wire), but I assumed any wire would work with the screen switching if it needed to?

Thanks. Here's a picture of my controller board and display. Nothing's been modified yet.

Re: GearBest Screen Doesn't Power On

Posted: Sun Nov 05, 2017 3:48 am
by fraggle
I've found on most of the screens white wire is AV2 and yellow is AV1 - and yes in every case the screen auto switches the source based on its inputs.

First thing I would check is that the PI is not actually outputting to HDMI - and force it to use composite.

Try setting display_mode to 3 in config.txt to force composite PAL mode. i.e.
display_mode=3

Then reboot - any joy?

Re: GearBest Screen Doesn't Power On

Posted: Sun Nov 05, 2017 11:47 am
by rodocop
That screen does not need a mod to work on 5v. Just try to run it with 5v from the pi. I've only ever used then with pi zero, so I'm not sure how to even wire to a pi3.

Edit:
Looked it up pp24 is the composite on the pi3. Try with the yellow wire, and 5v and ground to the pi.

I've also always used the yellow wire for av1. Also, be sure you have a proper image on your pi3 because even with power it will not display anything until you have an image. (Im sure you have an image. But it can't hurt to ask)

Re: GearBest Screen Doesn't Power On

Posted: Mon Nov 06, 2017 9:13 pm
by skorpien
Thanks for the help :) I got it working.

I re-soldered everything, using the yellow wire and connecting 5V/ground to the Pi itself, edited the config.txt, and it's working great.

I do have a question (more a curiosity really): Between NTSC and PAL, is there any noticeable difference?

Also, do you guys have any favorite themes for a small screen? I'm leaning towards the nes mini theme but I'm not a fan of the description on the games list.

Re: [Solved] GearBest Screen Doesn't Power On

Posted: Mon Nov 06, 2017 10:36 pm
by YaYa
Our screens are very small so you won’t find a decent theme that displays game infos.

Many people here are using either Pixel or GBZ35 theme.
I am using GZ35 and it’s very clean and displays very well.

Re: [Solved] GearBest Screen Doesn't Power On

Posted: Mon Nov 06, 2017 11:09 pm
by skorpien
Oh, no, I was looking for a way to remove the info. Really was just interested in the name of the game and a picture. And a way to see other games in the list.

GBZ35 is a great looking theme. I think I'll be using that one. Thanks :)

Re: [Solved] GearBest Screen Doesn't Power On

Posted: Mon Nov 06, 2017 11:23 pm
by YaYa
Ok i thought you were not a fan by the way the description was displayed by the nes mini theme lol. So you’ll be happy, GBZ35 is showing just game list and picture