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My poor man's NES Flash Cart

Started by 133MHz, September 23, 2007, 01:46:28 am

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133MHz

Hi everybody! ;D

This was actually a while ago (like between July and August 2007), but I remodeled my room so I had to put my gaming stuff aside for a while, and now I'm getting everything back to order, so I present you my poor man's NES flash cart.

The story: I was in the mood of playing some Antarctic Adventure (LOVE that game seriously, I'll never get tired of it, even the music :P) but on the real NES, I first saw that game around 2000, when I was in middle school and a classmate lent me a Famicom pirate cart (a very good one) with that game in. Returned the cart a week later, never saw her again. But the game stood in my memory for years ;D. So I wanted to play it again on the console and not emulation.

But I'm out of money, so no original game/repro/multicart/EPROM burner-eraser/Powerpak for me, I have to do it without spending a single cent. Actually that's most (if not all) of my philosophy ;D. I'm always making ghetto McGyver-esque electronics stuff because I'm a cheap bastard ;D

I tend to accumulate lots of electronics junk (mostly from computers, TVs and monitors) so I had to do it with parts lying around here, and with zero money.

Enough about history, now to the game :D:

Antarctic Adventure is Mapper zero, 24KB game : 16KB PRG and 8KB CHR (if my memory serves me well). That makes things a lot easier. So I search for a mapper 0 cart for sacrifice and I find...

...this Elevator Action cart.

So now all I have to do is replace the PRG and CHR ROM from the cart with my own chips with the Antarctic Adventure data burned on them. I have lots of EPROMs lying around but no programmer and eraser to work with them, and that kind of equipment is expensive. I have some Pentium motherboards lying around with 128KB Flash ROM chips for the BIOS. Yeah, I actually junked a pair of motherboards just to play Antarctic Adventure on my NES ;D.

I used Translhextion (an hex editor) to strip the iNES header, and separate PRG and CHR data, also to repeat each one several times to fill each chip. Ended up with two 128KB files, one for the PRG chip and one for the CHR one. Put them in a 200MB hard drive with MS-DOS and Uniflash (an universal BIOS flashing program) and improvised a rig with a Pentium motherboard to flash the chips.

This is the flashing rig:

Notice the piece of paper passed under the BIOS chip for easy removal :P

The procedure is simple: Boot the Pentium based computer, let it load DOS, load Uniflash, tell it to flash the computer's BIOS, point it to use your PRG ROM file, let it flash. When it's complete, swap the chip (with the computer still on), then flash the CHR ROM file onto the second chip, turn off computer, et voila! Now you have your ROMs and the motherboard is trashed since there's no BIOS so it will not boot anymore!

Here you can see the Uniflash user interface, yeah that's a 9" monochrome monitor I got like for 3 bucks at the flea market.


So now with the chips ready, I have to adapt them to the board since they're much bigger in size and pin count, also the pin count is not standard and some pins (particularly the programming ones) are not needed. I removed the Elevator Action ROMs from the board, ripped two IC sockets from some junk boards and stripped some old IDE cable to make the connections.

Here you can see the first socket done. Note the notebook on the back, which I use to match the corresponding pins and mark the connected ones. Since I'm only using the first 32KB of the 128KB chips, the higher address lines must be grounded or put to +5V (doesn't matter, since the data is repeated all over the chip) just don't leave them floating or it will produce unpredictable results.


I broke a trace when removing one of the chips, but some hot glue fixed that. Now the chips are ready to install:


Chips installed, ready to go. Cutting, stripping, tinning, matching, soldering all those wires was a pain in the ass. I did one chip in one day, and the other chip the day after:


I hope the cart closes now, those things bulge a lot ;D:


Now it's time to try the thing:


IT VERKS! IT VERKS! :D :D :D :D :D

Now excuse me, It is my intention to sit down and play some Antarctic Adventure ;)


Conclusions:

* Total cost of the project: $0.000
* Fun provided by Antarctic Adventure: Lots, lots of it.
* Computer motherboards trashed in the process: 2
* Making a flashable NES cart with junk lying around my house: Priceless.

One day (when I get a printer) I'll make a proper label for the cart. Also as you see there is possibility for expansion, even if it's just a Mapper 0 cart. With no mapper the max. amount of storage directly accessible for the NES is 32KB, I can 'divide' the 128KB chips in 4 32KB 'segments' by putting switches on the higher address lines, that way I can make a 4 game multicart, and the games are selected by flipping a pair of switches. I know there are not a good lot of mapper 0 games to choose around, most of them are in multicarts anyway, but there is some interesting homebrew and ROM hacks which fit on those 32KB, like Super Mario Forever (also known as the hardest SMB hack ever, widely known by its Youtube video), the NES test cart, etc.

Supersize pics coming soon!

manuel

What can I - who knows less than NOTHING about this stuff - say more than WOW?
If I had the skills I would probably do the same, but I haven't, so I just sit here and amazedly wonder about what other guys can do with old electronics. ;D

FamicomFreak

That's some great stuff and it was worth it for such a great game! We are lucky to have a guy like you in this forum to show us your great awesome projects!
Retro Gaming Life  www.retrogaminglife.com

Doc

*Faints because Antarctic Adventure is his favorite Famicom game ever.* :o

Har the cat

How can someone be so technic!?   :o
Intergalactic cat says: Is this planet Earth?

NationalGameDepot

Very cool project.  I wish I had techy skills to do anything :-\
~~NGD

133MHz

Thanks guys for all the great comments ^_^

Actually I got a replacement BIOS chip (from a similar but burnt mobo) so I can boot the sucker again and flash my cart as many times as I want ;D. Maybe in the near future I'll convert it into a four game multicart.

FamicomFreak

Quote from: 133MHz on September 23, 2007, 04:19:26 pm
Thanks guys for all the great comments ^_^

Actually I got a replacement BIOS chip (from a similar but burnt mobo) so I can boot the sucker again and flash my cart as many times as I want ;D. Maybe in the near future I'll convert it into a four game multicart.


haha I was about to mention about the four game multicart thing. It would be really kewl to have NES multi carts hey you can even make a business with it!! wekekkekee
Retro Gaming Life  www.retrogaminglife.com

133MHz

If I ever do the 4 game multicart thing, this is my set list for now:

* Antarctic Adventure
* Elevator Action (the cart's original game)
* Super Mario Forever (aka the hardest mario hack ever - putting it on a cart is pure evil)
* ????

Any other recommendations for mapper 0 games? ;D

manuel


keiffer01


133MHz

Excitebike and Pacman are on my pirate multicarts, and I have a SMB2j pirate cart ;D

MarioMania

Witch SMB2J Cart you have...the No Title Srceen one,  I have that one

Can you do like a NES SMB hacked one

133MHz

Quote from: MarioMania on September 26, 2007, 01:25:27 pm
Witch SMB2J Cart you have...the No Title Srceen one,  I have that one


Yup, that one.

Quote from: MarioMania on September 26, 2007, 01:25:27 pm
Can you do like a NES SMB hacked one


Yeah, that's what Super Mario Forever is! (well there's a PC game called the same by Buziol Games), look for 'super mario frustration' on youtube/google video and you'll see it.

Paul-FC