Creating simple cart

Hi all. I'm kinda new to this whole thing so please excuse my ignorance. I have a hack of SMB that I would like to burn on a cartridge. I'm having a hard time getting it onto a cart though. I purchased an EPROM burner and some 27C256 ROMS:

THE BURNER: Flash Writer/Programmer With USB Interface

THE ROMS: 27C256

I went down to the local game exchange shop and got some Mapper 0 carts NES NROM256-02 (i think it was golf or baseball) and an NES NROM128-01 cart. I took off the CHR and PRG chips, put in a socket (i bought this socket: SOCKET) and I burned some of the 27C256 roms, put them into the socket and now i'm getting a gray screen. So really i'm going back and i'm trying to figure out where I went wrong - I think it is the way i've burned the 27C256 ROMS. My questions are:

1) The CHR and PRG files are much less than 32k (27C256 rom). I was reading that the CHR and PRG file may need to be burned multiple times on the ROM so they equal 32k (ie CHR 8k x 4 = 32k). If this is the case, what would be the best way to accomplish this. I'm on a MacBook (Tiger 10.4) but could do this in windows if it's easier.

2) Can I put SMB hack onto an NROM128 cart?

Also, are there any other recommendations or from the steps above does it look like i'm doing something wrong.

BTW - I really started getting into this because of an artist that taught a class on new media art at my college. If anyone hasn't heard of him, definitely check out his site - he is doing some great work:

Cory Arcangel

The PRG in SMB is 32KB exactly, so it should fill the entire chip. The CHR is 8KB, so you should repeat it 4 times. You could use an hex editor for these things, but I usually use the Windows/DOS prompt for this (the command COPY /B SMB.CHR + SMB.CHR + SMB.CHR + SMB.CHR SMB32.CHR will do it).


No, the "128" part tells you it can only handle 16KB. You could probably modify it to handle 32KB, but I wouldn't know exactly how.


You should get a multimeter and check every pin to make sure you soldered the socket in right. You know, it's a lot of pins, and it's easy to end up with bad contact or short circuit some of them.

I can get paranoid sometimes, so also usually check the whole circuit. With the chip in the socket, I check the contact from each leg all the way to the respective pin on the board (you know, the bottom part that plugs into the console - use the cart pinout guide to know wich pins are wich) to make absolute sure that there are no bad contacts.

If the contacs are OK but you still get a grey screen, you're probably programming the chip wrong. Doesn't your programmer have a function for reading the chip back? That will clear things up.