Author Topic: Cant dump the n64 test cart and gameboy test cart roms.  (Read 1678 times)

Offline fintogive

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I have 2 hard to find test carts ive been trying to dump. the retrode was my last hope.  n64 test cart as there doesnt seem to be a method to properly dump this cartridge. the n64 test cart unique cart with four 2mb flash rom chips in side the cart.  the game shows up as genericgamedata.dat but even forcing n64 or increasing the size of the rom.  it wont work on any emulator ive tried it with.   

As for the GB test cart it does recognize as a GB game rom at the correct size of 32kb or (256).  however it wont run on any emulator and only somewhat runs in a corrupted form on visualboyadvanced. heres the odd part ive dumped this cart with various or the same settings and every time i dump it the results are different in the emulator.  its either blank or boots with words that arnt colored correctly or corupted and crashes.

So is i possible to edit the firmware for these to be accepted or did i miss something in the setting?  These carts are on a limited life spam once bit rot kills off both carts due to being eprom and eeproms/flash.
« Last Edit: 03/Aug/2016 08:52:11 PM by fintogive »

Offline Wannado

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Re: Cant dump the n64 test cart and gameboy test cart roms.
« Reply #1 on: 06/Aug/2016 05:11:47 PM »
I. General questions

1. Are you using the correct voltage for each game?
2. Did you test if both cartridges are working when used with a real N64/GB?
3. Are the contacts clean?
4. Which kind of Retrode (1 / 2) and which firmware version are you using?


II. About the N64 game

If it wasn't the voltage: Maybe the test cartridge's flash chips require unusual bus timings. AFAIK, the first four bytes stored in an N64 game cartridge indicate how fast it can be accessed.

The Retrode's size detection may fail if those four bytes have an unusual value. And since the Retrode is using fixed timings, it is possible that these are too fast for the flash. Though the Retrode tends to be slow compared to the typical timings used in N64 games.

You probably tried the following settings:
Code: [Select]
[forceSystem] N64
[forceSize] 8

Please post:
1. the first four bytes (as viewed in a hex editor, for example) from the ROM file and
2. the exact file name obtained with these settings.


III. About the GB game

We are talking about a classic GB (or maybe GB Color) game, not GBA, right?
How do you know that the size of 32 kiB (like Tetris) is correct?

Please open the ROM file in a hex editor and post the bytes from offset 140 to 14F hex (320 to 335 decimal).

Offline fintogive

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Re: Cant dump the n64 test cart and gameboy test cart roms.
« Reply #2 on: 11/Aug/2016 11:44:43 AM »
Thank you for your reply.

1.  3.3v n64   5v GB  Yes i am using the correct voltage.
2.  Yes they are both fully functional on original hardware.
3.  contacts have been carefully polished to a fine shine with super fine 0000 steel wool
4. retrode 2.  firmware version is v0.19 beta

Yes i have tried every size from 4mb to 64mb with force n64.   there is four 2mb eeprom flash chips inside of this cart. (more details on the hardware of this cart can be seen here.)
https://www.youtube.com/watch?v=xoPK-HpPa6c

theres no data in the rom file for the n64.  its all FF  which mean its not even detecting data on the cart...


as far the GB cart, its very unusual cart as it uses a full size eprom chip (like the nes) it was made in 1989 so its a GB cart.
 i looked up the chip number and its a was defiantly a 32k eprom chip.  ive tried other sizes but it doesnt make much of a difference...
i have a few dumps of the rom (same size) and noticed the first part of the rom data is
different on both dumps in the hex editor at the root of the data ( from offset 0000000 to offset 00000100)

heres the line of data  from 140 to 14f
45 53 54 20 00 00 00 00 00 00 00 00 00 E9 EF 59


Offline MasterOfPuppets

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Offline Wannado

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Re: Cant dump the n64 test cart and gameboy test cart roms.
« Reply #4 on: 25/Sep/2016 05:11:52 PM »
Sorry for taking so long to respond.

When I wrote my first reply, I somehow thought those were developer cartridges with test versions of games. Now I finally understood that those cartridges are tools used by support engineers to test console hardware.

As such, the test cartridges are designed to detect any deviation from the expected behavior of a real console. This feature might prevent the Retrode (which certainly does not behave exactly like a real N64 or GB) from reading the ROM properly. For example, a test cartridge might lock up intentionally to prevent taking damage (from operation in a broken console).

There is no easy way to find the real cause of the issue. The cartridges might have to be reverse engineered. I cannot do that. Performing firmware experiments seems to risky to me at this time, given so little information about the test cartridges' design.

The header data from the GB cartridge looks plausible. But I have no idea where the random part comes from, or what the section before the header is usually used for.

Offline fintogive

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Re: Cant dump the n64 test cart and gameboy test cart roms.
« Reply #5 on: 18/Oct/2016 10:23:31 AM »
Sorry for taking so long to respond.

When I wrote my first reply, I somehow thought those were developer cartridges with test versions of games. Now I finally understood that those cartridges are tools used by support engineers to test console hardware.

As such, the test cartridges are designed to detect any deviation from the expected behavior of a real console. This feature might prevent the Retrode (which certainly does not behave exactly like a real N64 or GB) from reading the ROM properly. For example, a test cartridge might lock up intentionally to prevent taking damage (from operation in a broken console).

There is no easy way to find the real cause of the issue. The cartridges might have to be reverse engineered. I cannot do that. Performing firmware experiments seems to risky to me at this time, given so little information about the test cartridges' design.

The header data from the GB cartridge looks plausible. But I have no idea where the random part comes from, or what the section before the header is usually used for.

well i did manage to dump the GB test cart but not wit hthe retrode.  im still trying to find a way to dump the n64 test cart.

the part before the header is some kinda test for the GB but for whatever reason the first 140 lines kept corrupting when dumping. the test cart its self there isnt much to it actually.  its a board with a single 32k eprom soldered to it.  thats it.  no security chips or other circuits other than a capacitor.

Anyways i had to buy an everdrive 64 and use a dumping program for the everdrive to dump the GB cart. which didnt work either luckily the programmer saturnu was still actively working on it and fixed it to dump the cart rather quickly too.

so there is no way to dump the n64 test cart? cause i keep batting zero with finding a way that isnt expensive.  but it looks like ill have to get a v doctor to dump this dang cart.  is there any way i can help?

anyways thanks for the reply.