Hacking EZ Flash Jr. Stuck in Boot Loop

[ShishKebabsMin]

Hi folks,

Just got my EZ Flash Jr. in, I was stoked to try it out. Had the SD card ready to go, put it all together, plugged it in, turned on the Game Boy, and I get a brief view of the EZ-FLASH splash screen before the Nintendo logo starts falling again. This loop goes on and on and on.

I've been around the forums looking for solutions, but nothing has worked. I have an original Nintendo Game Boy Pocket fitted with a 3rd party IPS screen (according to the specifications, backlit mods are fine, does that include IPS screen?)

Here's what I've tried, all resulting in the same problem:

• 2 different MicroSD cards, one 16GB (Sandisk), the other 32GB (Samsung). Both are class 10.
• Fresh single-use batteries.
• Fully charged rechargeable batteries.
• Formatted to FAT32 in both Windows and Linux, with 32kb block size and full formats on both OS's and both MicroSD cards.
• Verified the SHA signature of downloaded files.
• Copied files to MicroSD from both Windows and Linux.
  
• Reduced brightness of screen to minimum.

And these give different results:

• Turn on without MicroSD card, boot loop does not occur in this case, it sits at the EZ-FLASH splash with "LOADING..."
• Turn on with empty MicroSD card, I get a warning that the ezgb.dat file is missing.

Not sure what else to try, could the unit be faulty?

 

[Shadow#1]

Hi folks,

Just got my EZ Flash Jr. in, I was stoked to try it out. Had the SD card ready to go, put it all together, plugged it in, turned on the Game Boy, and I get a brief view of the EZ-FLASH splash screen before the Nintendo logo starts falling again. This loop goes on and on and on.

I've been around the forums looking for solutions, but nothing has worked. I have an original Nintendo Game Boy Pocket fitted with a 3rd party IPS screen (according to the specifications, backlit mods are fine, does that include IPS screen?)

Here's what I've tried, all resulting in the same problem:

• 2 different MicroSD cards, one 16GB (Sandisk), the other 32GB (Samsung). Both are class 10.
• Fresh single-use batteries.
• Fully charged rechargeable batteries.
• Formatted to FAT32 in both Windows and Linux, with 32kb block size and full formats on both OS's and both MicroSD cards.
• Verified the SHA signature of downloaded files.
• Copied files to MicroSD from both Windows and Linux.
  
• Reduced brightness of screen to minimum.

And these give different results:

• Turn on without MicroSD card, boot loop does not occur in this case, it sits at the EZ-FLASH splash with "LOADING..."
• Turn on with empty MicroSD card, I get a warning that the ezgb.dat file is missing.

Not sure what else to try, could the unit be faulty?

Try on a official unmodified system

 

[ShishKebabsMin]

Alright, so I got a hold of an unmodified Game Boy Color and can confirm it does work with that unit. It seems the IPS display is incompatible with Ez Flash Junior on the Game Boy Pocket at least. A real shame! Any idea why that is? Seems to be the screen and the cartridge are both competing for limited power, and the screen wins.
Now I want to upgrade the screen in the GBC, is it known what backlight/IPS screens are compatible with the EZ Flash Junior, if any?

 

[Shadow#1]

Alright, so I got a hold of an unmodified Game Boy Color and can confirm it does work with that unit. It seems the IPS display is incompatible with Ez Flash Junior on the Game Boy Pocket at least. A real shame! Any idea why that is? Seems to be the screen and the cartridge are both competing for limited power, and the screen wins.
Now I want to upgrade the screen in the GBC, is it known what backlight/IPS screens are compatible with the EZ Flash Junior, if any?

Told ya knew that was your problem

 

[The Real Jdbye]

Alright, so I got a hold of an unmodified Game Boy Color and can confirm it does work with that unit. It seems the IPS display is incompatible with Ez Flash Junior on the Game Boy Pocket at least. A real shame! Any idea why that is? Seems to be the screen and the cartridge are both competing for limited power, and the screen wins.
Now I want to upgrade the screen in the GBC, is it known what backlight/IPS screens are compatible with the EZ Flash Junior, if any?

Which IPS kit do you have? I just bought 2 DMG Game Boys, 2 Ezflash Jr's, custom shells and RIPS v4 kits and other tidbits, and it would suck if they won't work with the Ezflash Jr's once modded.
The V4 kits and the Retro Pixel kits use a smaller more square screen than the v3 kits and older so they don't waste most of the screen area, so I figure the battery draw is lower.
If it doesn't work, I have a backup plan though. I figure some combination of these two should allow things to work:
https://retrosix.co.uk/CleanPower-V2-Game-Boy-Original-p141361110
https://retrosix.co.uk/CleanJuice-XL-USB-C-Battery-Pack-Game-Boy-Original-p206293430

I have seen people use the V4 kits with Ezflash Jr successfully so hopefully there are no problems.

Edit: Fixed a wrong link

 

[ShishKebabsMin]

I'm unable to share links until I hit 5 posts, but if you go to Retro Modding dot com, the screen I installed is the "Game Boy Pocket IPS LCD." It doesn't seem to have any branding.
Thanks for sharing the link to the CleanPower board, there doesn't seem to be an equivalent for the Pocket unfortunately.

--Edit
Found this video with a GBC IPS screen that does play nice with the EZ Flash Junior, although it shows the same symptoms I had with my Pocket when at full brightness. I'm tempted to give it a punt if there are no other suggestions.



--More edits
I've seen talk of voltage regulators possibly helping out, has anyone had any experience with this in terms of getting EZ Flash Jr to work with an IPS screen on a Pocket?

 

[IzzyFoShizzy]

I'm unable to share links until I hit 5 posts, but if you go to Retro Modding dot com, the screen I installed is the "Game Boy Pocket IPS LCD." It doesn't seem to have any branding.
Thanks for sharing the link to the CleanPower board, there doesn't seem to be an equivalent for the Pocket unfortunately.

--Edit
Found this video with a GBC IPS screen that does play nice with the EZ Flash Junior, although it shows the same symptoms I had with my Pocket when at full brightness. I'm tempted to give it a punt if there are no other suggestions.



--More edits
I've seen talk of voltage regulators possibly helping out, has anyone had any experience with this in terms of getting EZ Flash Jr to work with an IPS screen on a Pocket?

I've got this regulator on the way for my GBP. I'll let you know how it goes because I get the boot loop on mine as well.

--------------------- MERGED ---------------------------

I've got a Pololu 5V Step-Up/Step-Down Voltage Regulator on the way for my GBP that is having this boot loop issue. I'll let you know if that resolves it.

 

[IzzyFoShizzy]

Good news! The Pololu 5V Step-Up/Step-Down Voltage Regulator fixed the issue. EZFlash Jr boot up and runs everything without any issues.

 

[SirFranko]

Good news! The Pololu 5V Step-Up/Step-Down Voltage Regulator fixed the issue. EZFlash Jr boot up and runs everything without any issues.

Edit: I found the units.

Do you have any pictures of the install?

 

[MadBob]

I added the FunnyPlaying GBC IPS v2 and it works perfectly with the EZF Jr

https://funnyplaying.com/products/gbc-retro-pixel-ips-lcd-kit-1?variant=39377983504445