Hacking a MVS Multicart

Tighe

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So I opened up my 120-in-1 and snapped some photos.

The whole thing is just 3 Altera CPLDs, and bunch of Fujitsu Memory (all the same), and a 8 bit microcontroller with flash.

Microcontroller:
ATMEGA8L-8PI Datasheet - ATMEL Corporation - 8-bit AVR with 8K Bytes In-System Programmable Flash
http://www.alldatasheet.com/datasheet-pdf/pdf/80252/ATMEL/ATMEGA8L-8PI.html

CPLDs:
Altera EPM3256ATC144-10
http://www.arrow.com/item/detail/altera/epm3256atc144-10

Memory:
Fujitsu MSP55LV100S
There is a lot of people selling these, but I cannot find a datasheet anywhere.

My thoughts are that the menu is all controlled bt the microcontroller and if we can read the flash in it and hack it we can at the very least edit the menu.

If you look at the photos there are places to add more memory that are not used. I bet it would be possible to add more memory and more games!

Top board:
13%2520-%25208.jpg


Bottom board:
13%2520-%252011.jpg


CPLD:
13%2520-%25205.jpg


Microcontroller:
13%2520-%25206.jpg


Memory (all the same)
13%2520-%25207.jpg


Mysterious Cable 1 and 2 header!?!
13%2520-%25209.jpg


13%2520-%25202.jpg
 
I just noticed that my cart is a 120 in 1, but the board is screened with 138 in 1! That explains the 3 missing memory chips! ;-)

Does anyone want to open up their 138 and snap some photos??
 
What is really funny is to look at the labels on the memory, this memory was salvaged from all sorts of places, some has Chinese writing, others Japanese, and English too.
 
this will be a good thread. maybe we can get to a point where we can get every neo geo game on 1 cart.
 
You didn't post on my thread or vid but i'll post on yours!

Cool!!!

:D
 
Interesting. I'd start by dumping all those flash chips to see what's on 'em.

All those chips have epoxy on them, the microcontroller does not.

Also they are all smd mount.

Also what pisses me off is that when I got this there was no 138 board. That means that they planned on making the wee 138 with a few more games ahead of the time...
 
If you want an atmega8 chip dumper/programmer they are easy to make radio shack might have all the parts or around $10 and you'll need a pc running linux with a parallel port and a program called avrdude, i have a programmer already built if you want to borrow it
 
If you want an atmega8 chip dumper/programmer they are easy to make radio shack might have all the parts or around $10 and you'll need a pc running linux with a parallel port and a program called avrdude, i have a programmer already built if you want to borrow it

Well now all my computers are Linux in my house, I will be installing avrdude. I wonder if it is in portage...

I can compile it too.

I don't mind building the programmer, but I worry about accidentally erasing the microcontroller so I will probably buy a microcontroller to test writing and dumping on first.

Do you have done documentation on how to build one?
 
My 161-in-1 looks exactly the same as yours, only with one or two extra smd memory chips. It'd be nice if you could find a way to edit the menu, because I'd love to remove all the dupes/clones from mine
 
LOL I just got an e-mail from Mouser selling Altera CLPDs. :D


My 161-in-1 looks exactly the same as yours, only with one or two extra smd memory chips. It'd be nice if you could find a way to edit the menu, because I'd love to remove all the dupes/clones from mine

Seems that should be the easiest thing to do, pretty sure that dumping the microcontroller and hacking the dump should be how to do it.

How about some photos of the boards in you 160?

I figure the microcontroller controls the whole thing and the CLPDs are just used for bank switching. The microcontroller probably has all the address ranges for each game ROM and instructs the CPLDs to map those addresses to addresses the neo can read.
 
LOL I just got an e-mail from Mouser selling Altera CLPDs. :D




Seems that should be the easiest thing to do, pretty sure that dumping the microcontroller and hacking the dump should be how to do it.

How about some photos of the boards in you 160?

I figure the microcontroller controls the whole thing and the CLPDs are just used for bank switching. The microcontroller probably has all the address ranges for each game ROM and instructs the CPLDs to map those addresses to addresses the neo can read.

Sure thing Tighe, I'll grab some after I get home from work this evening.
 
I have two 138-in-1 boards, one working 100%, the other crashes when you try to go into a game. I can try to get some pictures of the boards this weekend of the 138 in one. My guess is one of the two headers you are wondering about is for the daughterboard of the 138-in-1, which is what allows you to control and modify the game list in the menu.
 
I'm naively hopeful about this. Maybe some good ol' merican enginuity can prevail.
 
OK here's some reference material... I built mine quite some years ago and can't find the original document, but I'll upload some pictures maybe tonight so you can check out my homebrew skillz lol

here's just a crash course in atmega8
http://sbc.rictor.org/io/atm8prg.html


Here's a link to build a pretty nice programmer
http://nahians-avr.webs.com/parallelportprogrammer.htm

This one looks a lot like mine, mine is a really ghetto version of this. I used just an IC socket and soldered right to the legs instead of the fancy chip bed this one has lol. I wanted to just mount the the IC socket right on top of a little project box and have a dongle that just comes out and connects to the computer I never got around to it though.

AND mine does have an LED on it so I know when the chip is being accessed.

atmega8 is a great platform, really easy to get into and learn on

let me know how you make out with building this, i see this last guy was using PonyProg, i've never used it, but it looks a hell of a lot less complicated that avrdude plus it runs on windows, looks pretty basic, you can probably get it to load in wine
 
another thought occurred to me... if you start dumping, there's a really good chance you might actually be able to develop your own carts, if you can source the proper materials... i have zero exp with those altera max cplds, i'll check out some data sheets... the rest of it looks super basic... just a thought... a far off thought, this exercise will be a good proof of concept if you are able to modify the user interface and be able to load a custom rom set into memory...


baby steps though, i'd really like to see that atmega8 dumped
 
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