Veteran's 2nd GBZ (HDMI Screen) (Completed)

[snoek09]

Flat HDMI cable + Adapters (China)
https://www.aliexpress.com/item/FPV-Mic ... 20ceeb638a

Which are the right adapters to order? There are so many....

- C1 Mini HDMI Male
- A2 HDMI up

[Hyrulian]

Hi Veteran,
After reading the forum and seeing all the detail that you put into your builds and posts I decided that building a Gameboy would be the perfect summer project. I am new to modifying pre-made electronic boards and was wondering how you went about removing the GPIOs, power switch and micro-USB from the Kedei display? I was also wondering if the thin ribbon cable with four lines is the one attached to the touch screen?

[VeteranGamer]

Hi Veteran,
After reading the forum and seeing all the detail that you put into your builds and posts I decided that building a Gameboy would be the perfect summer project. I am new to modifying pre-made electronic boards and was wondering how you went about removing the GPIOs, power switch and micro-USB from the Kedei display? I was also wondering if the thin ribbon cable with four lines is the one attached to the touch screen?

i used the my soldering iron and a solder sucker....

solder sucker




removing the GPIO can be made a little easier if you remove the plastic first.....


(images taken off the net)


the trickiest part is removing the USB port....
as the GPIO and switch are just a case of heating the solder and removing/pushing the pins out...

the USB is connecting to traces on the board as well....
i would leave this until the end (get some practice on the other bits first) as you could end up damaging the traces....
(if you are unfortunate to damage any of the trace when removing the port, not all is lost there can be a work around)




Good luck....
and don't hesitate to ask or query anything your unsure about.....



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[Hyrulian]

Thanks this really helps. To get to the back side of the board did you remove the screen and the metal holder that it sits in?

[VeteranGamer]

Thanks this really helps. To get to the back side of the board did you remove the screen and the metal holder that it sits in?

you have to separate the board from the screen.....
once the screen is separated it doesn't need to be touched (removing the touch layer is a choice, not a necessity)



(images taken off the net)




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[Marty33]

Thanks VeteranGamer for all the details! I'll get started soon!

[VeteranGamer]

Thanks VeteranGamer for all the details! I'll get started soon!

Thanks....

and good luck with the build....



not to complicate things...
but i would highly suggest/recommend for you and anyone else using a Kedei HDMI screen to check this post out....
(just in case anyone has missed it)


https://sudomod.com/forum/viewtopic.php ... 578#p63572
(https://github.com/floppes/RTD266xFlash)


i personally havent got around to doing this (yet), but for me its something that can make your build just that little different to all the rest
(you can easily come up with you own design, which i plan on doing)





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[NPlayer]

Hi Veteran!

Loving your builds. I'm on the final stage of my own build and I'm having problems with my kedei screen. Maybe you can help me, or remeber someone who had the same problem. I've searched and I found nothing.

I also made the power save mod to the kedei board, just for reference. Everything goes well until I select some roms, or some menu like audio, etc. The screen goes glitched and the raspberry pi (a zero w) reboots. Other times the screen goes black, and the pi is somewhat shut off directly. In that case, the power rail board gives me 2.5 V aprox. Some games work, some nes roms. But MD, GB, GBC, etc. failed. Just once I started one MD game. If I try to conect the raspberry to the TV thought HDMI, everything works flawlessly.

So I'm conviced something is wrong with my kedei screen. I don't know if it's a power issue. 1V8 and 3V3 are connected to the raspberry, the 5V are connected to the power rail, just like the raspberry itself. Ground is common to both boards. There is no touching pins, everything is kapton protected.

Something with software? I have the config.txt from ZeroBoy web, don't know if there is one better.

If your or somebody can help me, I would really appreciate it. Thank you!

[VeteranGamer]

I also made the power save mod to the kedei board, just for reference. Everything goes well until I select some roms, or some menu like audio, etc. The screen goes glitched and the raspberry pi (a zero w) reboots. Other times the screen goes black, and the pi is somewhat shut off directly. In that case, the power rail board gives me 2.5 V aprox. Some games work, some nes roms. But MD, GB, GBC, etc. failed. Just once I started one MD game. If I try to conect the raspberry to the TV thought HDMI, everything works flawlessly.

So I'm conviced something is wrong with my kedei screen. I don't know if it's a power issue. 1V8 and 3V3 are connected to the raspberry, the 5V are connected to the power rail, just like the raspberry itself. Ground is common to both boards. There is no touching pins, everything is kapton protected.

its definitely a power issue issue.....

not sure if its the mod you've done, as i personally haven't done this yet (its a possibility).....


but the screen is notorious for demanding a good 5V power supply/connection....
even without the mod you've done, these issues have accrued (speaking from personal experience)....

now becasue youve imletment a power saving mod, i cant really advise/suggest you to try how i wired it to resolve the issues i've had as it would mean to move the 5V in to the LCD board to another location (and that just wouldn't work with the mod you have)

but i would suggest that you make sure what ever your powering the system with, is able to give enough power that it needs
(especially the the LCD)
also beef up the wires (if needed) for the LCD, as the AWG of the wire does make a difference when it come to power....
(especially as your trying to also save power in the mod your doing)



as for the config.txt.....
i'm not sure what the other site is offering, but it cant be that dissimilar to what everyone else has.....

the config.txt shouldn't make a difference in this instance....




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[NPlayer]

Truth is, the wiring, the measures, the board, the butchering, everything in this board is a PITA. I think I’m going to switch for a composite one.
Even audio is not working right know, so I prefer to use a composite screen and a usb sound card :’(