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 Post subject: Catridge Clone
PostPosted: Thu Aug 08, 2013 2:30 pm 
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Joined: Thu Aug 08, 2013 2:14 pm
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Hello, i'm new here, with the idea of ​​having clock tower in Spanish, I began to find some donor and I have found these two pcb strange, chances that must be clone, upload this image if anyone serves, on the other hand, the Killer Instinct contains no chip MAD-1 or MAD-2, perhaps it can serve as another option, the chip is called LGS 9539 (GD74LS00)

Image
Image
Image
Image

regards


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 Post subject: Re: Catridge Clone
PostPosted: Thu Aug 08, 2013 2:51 pm 
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Location: Seattle
No offense, but is there a question? Or are you only providing information?
skarstoker wrote:
the chip is called LGS 9539 (GD74LS00)
For you own future reference, the 74LS00 is the important part there. (L-GS is the IC manufacturer, and 9539 indicates the IC was made in the 39th week of 1995)


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 Post subject: Re: Catridge Clone
PostPosted: Thu Aug 08, 2013 3:00 pm 
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lidnariq wrote:
No offense, but is there a question? Or are you only providing information?
skarstoker wrote:
the chip is called LGS 9539 (GD74LS00)
For you own future reference, the 74LS00 is the important part there. (L-GS is the IC manufacturer, and 9539 indicates the IC was made in the 39th week of 1995)


Thanks for the info, I had no idea of that.
Actually I wonder if these IC is what replaces the MAD-1

I would like to know who could replace MAD-1 or MAD-2?


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 Post subject: Re: Catridge Clone
PostPosted: Thu Aug 08, 2013 5:47 pm 
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MAD-1 and MAD-2 are simply address decoders with a built it voltage supervisor for managing the battery-backed SRAM. Their purpose can easily be replaced by discrete logic (as shown with your Killer Instinct board, the 74LS00 is just 4 NAND gates). Nintendo actually did this on official carts too, though they typically used the 74LS139, which is a dual 2-to-4 decoder. If you were unsure, your carts are indeed clones.


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 Post subject: Re: Catridge Clone
PostPosted: Thu Aug 08, 2013 8:40 pm 
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qwertymodo wrote:
MAD-1 and MAD-2 are simply address decoders with a built it voltage supervisor for managing the battery-backed SRAM. Their purpose can easily be replaced by discrete logic (as shown with your Killer Instinct board, the 74LS00 is just 4 NAND gates). Nintendo actually did this on official carts too, though they typically used the 74LS139, which is a dual 2-to-4 decoder. If you were unsure, your carts are indeed clones.


thank you very much for the info now I is becoming clearer, but still I have the following doubts

these address decoders are programmed or not?
how can replace with electronics discrete?


so sorry i am noob , but by little you learn new things

I replaced some games following tutorials, but I have no donor :( [and here in my country, old games sell very expensive. so I thought that maybe you could create one on a protoboard].

Thank you very much for your answers.


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 Post subject: Re: Catridge Clone
PostPosted: Thu Aug 08, 2013 9:39 pm 
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Location: Mountain View, CA, USA
What you're attempting to do is, I think at this point, beyond your skill level. You don't just go out and "buy random SNES carts" and think "hey I'm just gonna drop in a replacement game". It takes a bit more work than that, and a hell of a lot more education/familiarity than what you're at right now (no offence). For example:

How did you plan on getting Clock Tower (the game itself -- link is for those who aren't aware there's a game called Clock Tower) onto a chip, and what kind/type of chip?

Usually the answer is "an EPROM or EEPROM", neither of which uses the same pinout as what Nintendo uses for their DIP mask ROMs -- meaning in those cases board rewiring is needed (example).

Next, how do you plan on getting that chip onto a PCB (cartridge/board)?

Usually the answer to this is "I'll solder it on". To do that easily/cleanly you need a socketable board.

Your Contra clone cart has no sockets for the ROM (only a socket for an address decoder chip -- what it's used for I can't tell, I don't do EE). The "black blobs" you see on there are called "blob top" chips, they are literally just chips (in this case the ROM) dropped onto the PCB and held in place while epoxy is poured over the chip, "gluing" it to the PCB in the precise correct location so all the traces/connections line up. 99% of the time these are pirate carts. This cart is basically worthless for what you need.

Your Killer Instinct cart, on the other hand, has sockets -- but for what type of chip (EPROM, EEPROM, etc.) I can't tell immediately (someone else probably can). One or more of the "blob top" chips on this cart is the game ROM; Killer Instinct, to my knowledge, doesn't use SRAM so I'm not sure what the 2nd blob is, other than maybe the other half of the ROM. It does not have a MAD-1, but it does have some address decoders as qwertymodo said. The MAD-1 is the least of your concerns, if you ask me, and that will soon become clear.

What you should try to do is find out what an actual Clock Tower cart looks like. Nintendo brands all of their carts with a model number (ex. SHVC-1A5B, etc.), and that scheme can actually disclose a lot about the overall cartridge wiring and so on.

In fact, I found it -- here's Clock Tower:

http://www.snescentral.com/article.php?id=0889
http://www.snescentral.com/pcbboards.ph ... VC-BJ1M-20

You can clearly see here that the Clock Tower cart uses an SHVC-BJ1M-20, has two DIP mask ROMs, a MAD-1 (address decoder), a D411A (CIC security chip), a LH5216AD (16KB of SRAM), and a battery (powers the SRAM). What you need is a cart that has all of this, although you could rewire the cart to use only one mask ROM (might need another address decoder (not sure, again not an EE guy)), and the D411A can probably be bypassed.

What you currently have is worthless if you want to make the task easy on yourself.

I would suggest sticking with emulators -- it's a lot easier, way less stressful, and so on.


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 Post subject: Re: Catridge Clone
PostPosted: Thu Aug 08, 2013 11:08 pm 
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many thank you very much for all the help offered

I explain a little more, I intend to do:

this is the original game cartridge Clock Tower and these are the relevant facts:
Image

Name: CLOCK TOWER SFX
Speed​​: 31/FastROM
ROM Map: HiROM
Kart contents: ROM + RAM + BAT
Calculated ROM Size: 24 Mbits
SRAM size: 2KB (16Kbit)

The problem to apply the word translation patch up your weight:
Calculated ROM Size: 25 Mbits
so I expand the rom to 32 Mbits

MASKROM
The game I intend writing to a flash memory 29F032
Image


MAD-1 (this is where stalled, as you might replace this component)
I have understood that the address decoders are used when a game has more than one maskrom
are also present when games have the option to save
They feature a memory (2kb, 8kb or 16kb depending on the game), plus a battery

MEMORY SRAM
wanted to replace it with a LC3664R

CIC
I have understood that it is a protection chip, if not this will reset the console, I read about a mod SuperCIC, but the idea is to replicate it with some other CI

in short, put everything on a breadboard, to see if it might work



Any help serves
me before hand
thank you very much


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