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Posted: Mon Jan 01, 2007 2:29 pm
by tokumaru
hayabusafmw, don't be confused by those numbers. They are all in kilobits. To convert to kilobytes you have to divide them by 8. Meaning that the chips you bought can only hold 32 kilobytes of data, and you can only play with NROM with that ammount of memory.

I hope you didn't get the PLCC ones, as No Carrier said, because those use a different package and are not shaped to fit a NES cart.

If you plan on making UNROM or TxROM devcarts, I suggest you order some AT29C040's while they're in stock. I don't think any NES game (multicarts excluded) ever used more than 512KB for PRG or CHR.

Posted: Mon Jan 01, 2007 6:31 pm
by hayabusafmw
Wow you are right i am getting confused.....too much number , names , haha

it's Much to know.

http://www.futurlec.com/cgi-bin/search/ ... o=AT29C256

this is what i ordered x4.


With IC28 sockets


So for the Wiring that you talked about....

Which should i do ??

the 1 wire technique or multiple? ....

I guess ninja gaiden game is the same boat as (megaman?)
both are MMC1....

so was that the 1 wire trick you wanted me to do?

Posted: Mon Jan 01, 2007 7:57 pm
by Memblers
On your NROM board, check the PRG A14 line. See if it connects to the A14 line on the cart edge. If it doesn't connect, you'll want to wire that up.

Posted: Mon Jan 01, 2007 8:20 pm
by hayabusafmw
Image

this is the Excitebike i got.

I don'T know where the A14 would be...:S. I know the prg is on the right side tho

Posted: Mon Jan 01, 2007 8:24 pm
by Memblers
Well, tokumaru posted the pinouts on the previous page of the thread. It's all right there. The pins on the connector are also numbered, to make things easier. Find PRG-A14 and follow the trace to where it goes.

Posted: Mon Jan 01, 2007 8:39 pm
by tokumaru
hayabusafmw wrote:Which should i do ??

the 1 wire technique or multiple? ....
That's exactly as Memblers said. A14 on the cart edge must be connected to A14 on the chip. You can check that with a multimeter if you have one. If you don't, just buy a cheap one, you must have a way to check contacts if you plan to make devcarts.

Use the pinouts I posted before to see which pin is which. If A14 is not connected to A14 already, you have to do it.

The process to install a socket for larger chips on boards like UNROM, TxROM or SxROM will often require more than just one wire. You'll need to compare the pinouts of your Flash with the pinouts of the Nintendo ROM, and make sure that everything is connected to the right place.

EDIT:
Image
Just make sure these are connected.

Posted: Mon Jan 01, 2007 8:58 pm
by hayabusafmw
I see..


But if i wanna make my cart a MMC1 MMC3 enable one? does it affect i in the same way?

Like play ninja gaiden , megaman 1 2 ,


what modification are involved?


Im just trying to figure it all out

Im confused a little with Nrom, & MMC1 MMC3 , & all the other stuff

i try to put it all together. hehe.

Posted: Mon Jan 01, 2007 9:15 pm
by tokumaru
This board is an NROM board. There is no way you'll be able to turn it into another board. With this board you can only run NROM games. Connecting A14 to A14 like I said above is just so you are able to run all NROM games, not only the NROM-128 ones.

To run Megaman 1, you have to get some UNROM cart, install the sockets there and rewire as needed. To run Megaman 2 you need to buy a SGROM cart. To run Megaman 3 and 5 you have to get a TLROM cart.

Small modifications like turning a CHR-ROM cart into a CHR-RAM cart are possible (although not always simple), but turning an NROM cart into anything else is pretty much impossible.

If you didn't get it already: These "-ROM" are the names of the boards, and "MMC1", "MMC2", etc are names of mapper chips. Different boards can use the same mapper. All TxROM boards use MMC3, and all SxROM boards use MMC1, for example. Check this page for info on the different boards and mappers.

Posted: Mon Jan 01, 2007 9:35 pm
by hayabusafmw
Ahh i see

so basicly if i want to Play Megaman 2 i need a megaman 2 (or other cart that used the same...)


but i cannot take any cart to turn it into a ''free rom cart''

I understand more now!:)



So for now I don't mind it's a experience :)
so for now i will live with NROM games..

how is the modification you talked about possible (about bending the socket leg)

I will finish this cart

then i will try to find a Megaman ''ready cart''
to try an other project



Like i got a bootleg Famicom Super mario 3 i beleive (i got it in double)
i could do a MMC3 cart right?

I don't know about the chips tho ... if mine would be big enough ...

Also i got mario/duck hunt this would be a MMC1 right?...

Posted: Mon Jan 01, 2007 10:45 pm
by tokumaru
hayabusafmw wrote:so basicly if i want to Play Megaman 2 i need a megaman 2 (or other cart that used the same...)
Exactly!
but i cannot take any cart to turn it into a ''free rom cart''
how is the modification you talked about possible (about bending the socket leg)
We already told you a few times already, my friend!

The bottom line is that the A14 pin on the chip must be connected to A14 on the cart edge! Do it as you fell like.

The safest way would be to bend the pin of the socket up, so that it doesn't touch the board, solder a wire to it and the other end of the wire close to A14 on the cart's edge. But you should check the board first, maybe they are already connected and you don't have to do anything! If they are not, better do the bending thing.

I'll get home tomorrow, and maybe I can get a few pics of a bent pin. But I'm sure there are a few online already...
Like i got a bootleg Famicom Super mario 3 i beleive (i got it in double)
i could do a MMC3 cart right?
Probably. But since it's a pirate cart, we can't be sure. It might use a faithful MMC3 clone, but it may also use a different mapper, and the game was hacked to work on it. Also, many pirate carts use glop tops instead of regular chips, so there is no easy way to install sockets on such carts.
I don't know about the chips tho ... if mine would be big enough ...
I already told you that those chips you ordered are only good for NROM. Technically, you can make MMC3 carts with small memory chips, but that would be of no use for you since no commercial games were that small.

Posted: Mon Jan 01, 2007 10:48 pm
by tokumaru
hayabusafmw wrote:Also i got mario/duck hunt this would be a MMC1 right?...
I think it uses some weird mapper that no other cart uses. Also, if I'm not mistaken, this cart (even the original one from Nintendo) uses glop tops instead of regular chips, so they're no good for devcarts.

Posted: Tue Jan 02, 2007 8:35 am
by hayabusafmw
thanks for the help i understand a bit more




I found today in my game collection

Heavy shreddin (snowboard game) = mmc1

this is great i could use this one

but the screws in the back of the game are different i don't have the gamebit
that fits it.

neither my hardware store.
i think i already asked for them a while ago.

Posted: Tue Jan 02, 2007 10:09 am
by tokumaru
I also don't have the gamebits needed to open original NES carts.

Some people say it's possible to modify a regular screwdriver by carving the middle part or something, but I never tried that.

I open my carts by heating the screws with my soldering iron, while forcing the cart open. When the screw is hot enough, it melts the plastic only enough for it to come off. It works great, and doesn't deform tha cart case. I haven't tried to close them again, but I heard it is possible if you use larger screws.

Posted: Tue Jan 02, 2007 1:14 pm
by hayabusafmw
wooohoo!!

I had a Heavy shreddin cart (never play this game .)

it's a mmc1 cart

opened it like you said (minor damage there)

then ulsoldered the eproms

+ made a 10 x i should say 100x better hole in front aswell. ^_^
very proud of that

the next thing is to know how i will close it ... the screw plastic holder broke while in the process....
maybe electrical tape but it makes cheap.


I noticed what you meant there.... the Chr (has more legs like 32)
& the prg (i could use the same chips i had ordered?)
28 pin

let me know which fits in there so i will order 2 at least.

Posted: Tue Jan 02, 2007 1:47 pm
by hayabusafmw
Image[/list]