Hardware Homebrew Misc Firmware for GBC flashcart?

[OmDRetro]

i just bought one Game Flash GB OS.V4 Pro+ and of course it came with OS 1 installed on it.
I already opened a Dispute on Aliexpress because it's false Advertisement.

If it would have been OS4 that's on the Card I wouldn't care about it but because it's on OS 1 which sucks I'm not okay keeping it.

Question is: Did anybody tried the Modified Version of OS4 that Fabax01 Provided? i compared the Firmware File to the Original by using Total Commander and there are only 2 bits that are different.

If nobody tried this and Aliexpress wanting me to ship it, then I will give it a shot and see what happens...if it Bricks then i mean it proofs the Point that this Card is a fake and we know for sure if this Firmware can be used on those Fake Cards or not.
If it works then we can all Update...so if nobody reports back with confirmation then I will sacrifice my Garbage Device for it.

Either outcome i still got my EZflash Jr. which is a Million Times better anyway.

Yep, this is the exact OS I got(version 1), but luckily someone was able to share a modified version of OS v4.

Since I like taking risks so you don't have to, I tried this version of the OS which I think is exactly the same file melteolate shared. Only the Author part of the code was altered while everything else is the same... Amazingly, it worked. Looks like this is a clone of the Everdrive GB Classic and OSv4 IS its final version.

Everdrive GB Original series changelist:
v4 07.06.2017 1)Fixd bug in cheats function. v3 29.09.2015 1) Improved SD cards compatibility v2 06.09.2015 1) Swap A/B buttons in menu option 2) Minor bugfix

Comparison:

Checksums:

• CRC-32: E7B74777
• SHA-1: 28ED3A797DA3C48C309A4EF792147F3C56CFEC40
• SHA-256: 32EBB1ABCC1C601CEB9C4E3C4FABA0CAA5B85BB98C4F1E6612C40FAA528A91C9
• MD-5: 84C40473414CAF2ED4A7B1283E48BBF4

I attached two versions I found. One where GBOS v4 was patched by marv12345 to work on any clone made by KY Tech (patched GBOS found from elotrolado, but obviously UPDATE AT YOUR OWN RISK) and another that's guaranteed to work on the clone I have (Game Flash GB OS. V4 PRO+ Low Power Consumption).

Take note that you can't flash the firmware. You can only sideload it.

OS v1 permanently burned inside of cart, but cart will load OS from sd to ram, just like on n8 or edmd-v3, in case if OS file loaded to EDGB folder.

 

[devaser]

i just bought one Game Flash GB OS.V4 Pro+ and of course it came with OS 1 installed on it.
I already opened a Dispute on Aliexpress because it's false Advertisement.

If it would have been OS4 that's on the Card I wouldn't care about it but because it's on OS 1 which sucks I'm not okay keeping it.

Question is: Did anybody tried the Modified Version of OS4 that Fabax01 Provided? i compared the Firmware File to the Original by using Total Commander and there are only 2 bits that are different.

If nobody tried this and Aliexpress wanting me to ship it, then I will give it a shot and see what happens...if it Bricks then i mean it proofs the Point that this Card is a fake and we know for sure if this Firmware can be used on those Fake Cards or not.
If it works then we can all Update...so if nobody reports back with confirmation then I will sacrifice my Garbage Device for it.

Either outcome i still got my EZflash Jr. which is a Million Times better anyway.

Hello, i received the same
Don't know if there is much difference between 1 and 4 tho. Seems like just minor bugs.
I used the versión OMDRetro posted here and now it shows Version 4, it works fine. I didnt use the risky Marv one, i used the other.

 

[Jayro]

Either outcome i still got my EZflash Jr. which is a Million Times better anyway.

EZ-Flash Jr sucks major ass. The high power consumption is awful, and can cause "SD init" errors on boot, and the menu system is sluggish as hell when moving pages at a time. I'm much happier with my EDGB clone and dedicated RTC carts for Pokemon games.

 

[OmDRetro]

Hello, i received the same
Don't know if there is much difference between 1 and 4 tho. Seems like just minor bugs.
I used the versión OMDRetro posted here and now it shows Version 4, it works fine. I didnt use the risky Marv one, i used the other.

Both firmware's actually work on our clones, I mean you did mention that you do have the same flashcart as mine, the riskier firmware is the binary that only has the author-altered portion since the rest of it is a 1:1 copy. The safer firmware is the one edited by marv12345 as the brick code is patched out.

 

[Ferris1000]

I got good news, the Firmware that Fabax01 provided works and did not Brick my flashcard.
Finally there is an Option to swap A and B in the EDGB Menu.

I know I'm late with my response but i finally managed to test it.

All you need to do is to put the GBOS.GB into the EDGB folder on your SD Card.
If you get an error just remove the SD card, turn the GB on without the sd card and try again, that's how it worked for me.

You don't have to execute the GBOS.GB, just check the Firmware Option by pressing Select in the Main Menu and then About, there it should display OS Version 4.

 

[ChronoCrossfangirl2002]

I got good news, the Firmware that Fabax01 provided works and did not Brick my flashcard.
Finally there is an Option to swap A and B in the EDGB Menu.

I know I'm late with my response but i finally managed to test it.

All you need to do is to put the GBOS.GB into the EDGB folder on your SD Card. If you get an error just remove the SD card, turn the GB on without the sd card and try again, that's how it worked for me.
View attachment 483293View attachment 483294

does the RTC work for it?

 

[Ferris1000]

No, RTC doesn't work at all, not even if you keep the same Game in the Flash.
After doing my Research I'd found out that the Original Everdrive also doesn't have RTC and this is obviously a clone of the Original Everdrive GB (not the X7)

 

[Renjam]

I got one of these also os 4. The new roms I add to the sd card will not generate saves. The roms that came on the system seem to save fine. Having trouble figuring this out. any help would be appreciated

 

[Ferris1000]

Try a different sd card, those that come with the Everdrive clones are junk and will fail very quickly

 

[Peeteris]

Yep, this is the exact OS I got(version 1), but luckily someone was able to share a modified version of OS v4.

Since I like taking risks so you don't have to, I tried this version of the OS which I think is exactly the same file melteolate shared. Only the Author part of the code was altered while everything else is the same... Amazingly, it worked. Looks like this is a clone of the Everdrive GB Classic and OSv4 IS its final version.

Everdrive GB Original series changelist:
v4 07.06.2017 1)Fixd bug in cheats function. v3 29.09.2015 1) Improved SD cards compatibility v2 06.09.2015 1) Swap A/B buttons in menu option 2) Minor bugfix

Comparison:

View attachment 474850

Checksums:

• CRC-32: E7B74777
• SHA-1: 28ED3A797DA3C48C309A4EF792147F3C56CFEC40
• SHA-256: 32EBB1ABCC1C601CEB9C4E3C4FABA0CAA5B85BB98C4F1E6612C40FAA528A91C9
• MD-5: 84C40473414CAF2ED4A7B1283E48BBF4

I attached two versions I found. One where GBOS v4 was patched by marv12345 to work on any clone made by KY Tech (patched GBOS found from elotrolado, but obviously UPDATE AT YOUR OWN RISK) and another that's guaranteed to work on the clone I have (Game Flash GB OS. V4 PRO+ Low Power Consumption).

Take note that you can't flash the firmware. You can only sideload it.

Seems like those two files you attached are almost identical.
Both work on GB Pro+ Rev.H from 2024.

 

[AkikoKumagara]

I got good news, the Firmware that Fabax01 provided works and did not Brick my flashcard.
Finally there is an Option to swap A and B in the EDGB Menu.
View attachment 483293View attachment 483294

Tested on a whim. Working here, too. Being able to "correctly" map A & B is nice.

 

[Safidk]

I got good news, the Firmware that Fabax01 provided works and did not Brick my flashcard.
Finally there is an Option to swap A and B in the EDGB Menu.

I know I'm late with my response but i finally managed to test it.

All you need to do is to put the GBOS.GB into the EDGB folder on your SD Card.
If you get an error just remove the SD card, turn the GB on without the sd card and try again, that's how it worked for me.

You don't have to execute the GBOS.GB, just check the Firmware Option by pressing Select in the Main Menu and then About, there it should display OS Version 4.
View attachment 483293View attachment 483294

Hi,

First of all thanks for this post, this is awesome.

2nd. Just want to make 100% sure. Is it this firmware (see screenshot) you updated your card with?

Thanks in advance,
Safi

 

[Ferris1000]

Hi,

First of all thanks for this post, this is awesome.

2nd. Just want to make 100% sure. Is it this firmware (see screenshot) you updated your card with?

Thanks in advance,
Safi

The one from @Fabax01 is the one that works like in the Screenshot i attached.
Just extract and copy the EDGB folder to you microSD card.
It might not boot at the first turn on, if this is the case turn off your gameboy and turn it on again, then it should be on OS 4.
Don't execute it manually, all you need is to copy it to your microSD card and the Version will be OS4.

 

[OmDRetro]

Seems like those two files you attached are almost identical.
Both work on GB Pro+ Rev.H from 2024.

Thanks for reporting! It's not feasible to buy all the clone EDGB's out there so those with big wallets and a thirst for "adventure" greatly help here.

 

[SchuchWun]

I bought one of these off someone locally for about the price I'd pay for it off AliExpress and its pure garbage. I'm saving up to buy the legit everdrive version.

 

[AkikoKumagara]

I bought one of these off someone locally for about the price I'd pay for it off AliExpress and its pure garbage. I'm saving up to buy the legit everdrive version.

I mean... it's functionally identical to the EDGB that it's a clone of, unless I'm missing something. Never had issues with mine. Does what it's supposed to do. To be clear, I'm not arguing that it's equal or better than the x3, x5, or x7 Everdrive carts. Those are newer, faster, and better than the cart this is replicating.

 

[Jayro]

I mean... it's functionally identical to the EDGB that it's a clone of, unless I'm missing something. Never had issues with mine. Does what it's supposed to do. To be clear, I'm not arguing that it's equal or better than the x3, x5, or x7 Everdrive carts. Those are newer, faster, and better than the cart this is replicating.

I use the EDGB clone and dedicated RTC carts from Ben Benn for all my GBC needs, and it works great.

 

[SchuchWun]

I mean... it's functionally identical to the EDGB that it's a clone of, unless I'm missing something. Never had issues with mine. Does what it's supposed to do. To be clear, I'm not arguing that it's equal or better than the x3, x5, or x7 Everdrive carts. Those are newer, faster, and better than the cart this is replicating.

It's not. It barely launches games. I want to replace the microSD but I think that won't work.

 

[AkikoKumagara]

It's not. It barely launches games. I want to replace the microSD but I think that won't work.

I have one and it works fine. I don't really know what "it barely launches games means". Replacing the SD card is also fine, you just need to use one that is compatible with the thing. Mine's got a 4GB SanDisk micro SDHC that works, so that's probably a safe bet.

 

[pikapipi]

I tried but get the error 0xD3 and have no idea what it means. I probably broke it. Or more exactly bricked it when using the krikzz files. Does anoybody know what the error 0xD3 means? Is it unreparable broken for people who can not reprogram it?

What is annoying is that I just purchased it and only needed the files because the shitty SD card broke the moment I wanted to copy it.
I will probably have to send it back and get another one.

Post automatically merged: Dec 1, 2025

I tried but get the error 0xD3 and have no idea what it means. I probably broke it. Or more exactly bricked it when using the krikzz files. Does anoybody know what the error 0xD3 means? Is it unreparable broken for people who can not reprogram it?

What is annoying is that I just purchased it and only needed the files because the shitty SD card broke the moment I wanted to copy it.
I will probably have to send it back and get another one.

Edit the Flashcart makes a phasing humming sound. Like broken transistors probably.