nesdev.org

Hi peeps,

I'm needing a bit of help, if someone can shed some light it would be appreciated. I've been reading through the forums looking for info on this operation. My apologies if this has came up loads of times before.

I've removed the ROMS from an SMB3 cart to use as the donor. I have a 27C256 for the CHR ROM and a 27C512 for the PRG ROM. I'm using the 27C256 instead of a 27C128 because my progger wont program the 128. I have doubled up the CHR ROM to fit in the 256.

I have been reading http://www.nesdev.com/NES%20EPROM%20Conversions.txt to find out how to convert 27Cxxx eproms to work on a TSROM board. I see the 27C's are pretty much pin compatible except from A16, A17 and A18. This I think is where my problem is coming from. The conversions document above states ...

Bend up pins 1, 2, 24, 30 and 31 (or cut tracks 2, 24, 30 and 31)
Solder pin 2 to hole 24 (A16)
Solder pin 24 to GND (OE)
Solder pin 30 to hole 1 (A17)
Solder pin 31 to hole 2 (A18)

I have tied OE and CE of the eproms to GND; I've have aligned my eproms in the lower pins, which means I have no pins 1, 2, 31 and 32 (the 27C256 and 512 are 28 pin). According to http://nesdev.com/smb3_pinout.txt the pins match up, with the exception of A16-A18.

When fire up the cart, I get a grey screen, with no audio. Does anyone know what I do with A16, A17 and A18?

Also, the original SMB3 PRG rom is 256kb, the eprom I will be using for the 'new' game is 512kb. Will this mean I'll need to rewire more on the board?

Thanks for any input you can give.

EDIT: After seeing so many posts regarding this subject, I'm going to make a guide (nice pics etc). It will stop you guys having to see posts like these so often.

I've got it! Thanks anyways peeps. I'll get everything photo'd and get a guide put together.

Just use some 27c010 chips and double up the CHR & PRG as needed. Then you can follow the guide you already posted and your cart will work.

what´s wrong with the use of 27C256 for the CHR ROM and a 27C512 for the PRG ROM?!

Is it not possible to get them up and running?

It is possible, but not for this game

27C512 has only 64kb, 27C256 - 32kb.

But the PRG is 64kB and the CHR 16kB right?!

KeepGood wrote: EDIT: After seeing so many posts regarding this subject, I'm going to make a guide (nice pics etc). It will stop you guys having to see posts like these so often.

I've got it! Thanks anyways peeps. I'll get everything photo'd and get a guide put together.

I'm still waiting for your guide..

Banshaku wrote:

KeepGood wrote: EDIT: After seeing so many posts regarding this subject, I'm going to make a guide (nice pics etc). It will stop you guys having to see posts like these so often.

I've got it! Thanks anyways peeps. I'll get everything photo'd and get a guide put together.

I'm still waiting for your guide..

In lighter news I posted a diagram for CNROM 64k CHR support (AKA how to make a CNROM board run porno).

I'll make this diagram up for this cart also as soon too cause I know I'll do it where as others just dine and dash

nintendo2600 wrote:I'll make this diagram up for this cart also as soon too cause I know I'll do it where as others just dine and dash

Don't worry, I was not targeting you in any way I know that you contribute back and help them. It just the "dine and dash" ones that I don't have much sympathy for, especially when they just created an account, post a few time and disappear (which is not your case). I don't consider them part of the community.

Maybe we should put that diagram on the wiki then.

Banshaku wrote:

nintendo2600 wrote:I'll make this diagram up for this cart also as soon too cause I know I'll do it where as others just dine and dash

Don't worry, I was not targeting you in any way I know that you contribute back and help them. It just the "dine and dash" ones that I don't have much sympathy for, especially when they just created an account, post a few time and disappear (which is not your case). I don't consider them part of the community.

Maybe we should put that diagram on the wiki then.

Oh, I know you didn't mean me. I just wanted to post that diagram for all the "Dinner and Dash" bastards that waste our time and don't even have an ounce of courtisy or respect to contribute anything but expect everything. I figure if this diagram is up then maybe we won't have to see as many of their useless posts in the future.

If you want you can add my diagram that is in CNROM thread to the wiki also.

I read it and saw "Diner Dash" the first time. So who's going to clone Diner Dash on NES?

tepples wrote:I read it and saw "Diner Dash" the first time. So who's going to clone Diner Dash on NES?

Even just "Diner" AKA "Bugertime 2" would be cool to see on the NES.