Trying to "save" an old cart. Need help.

Hello!!
This is my first post here, but I have got lots of information from here lately, many thanks for being this great source of reliable information!
I just got an old and damaged pirate nes cart.
I tried to reassemble it on another board, but it did not boot.
It seems to be an AOROM. I used for reference this schematic:
http://elektropage.ru/cartmod/nes/nes_c ... matics.png

I took a closer look on the older board, and found that hc161 pin 3 was going to d2, instead of d0 and pin 5 was gnd instead of d2.
The pin going to rom a15 was the same, but I could not figure out wich pin was going to rom a16.
Made the changes on the board and still no succes.
I managed to dump the rom, but after adding a header, it didn't boot on any emulator.
Took a look at md5 from this rom and a working Diger rom without the header and they are different!

Maybe the rom is corrupted, or this simple change on the hc161 would make it as a new mapper?
If anyone can give me some help, I'll be thankfull!!

It looks like you did manage to dump the ROM, but some of the address/data lines are swapped, so the bits are scrambled. I'll see if I can descramble it...

Maybe the data was scrambled on purpose, so they made a little different mapper schematics.
If possible, could you tell me what is swapped?
Knowing this, I think will be possible to make some modifications on the board, boot and play this game again.

Compared to a normal EPROM pinout, the following pins have been reassigned:

13 = D2 instead of D0
15 = D0 instead of D2
23 = A9 instead of A10
25 = A8 instead of A11
26 = A11 instead of A9
27 = A10 instead of A8
23 = A8 instead of A10
25 = A9 instead of A11
26 = A10 instead of A9
27 = A11 instead of A8

There's no point in bothering, though. The contents of the ROM are identical to the USA version.

[Edited to correct pin reassignments.]

Cool!!
I'm going to try to make this rom work on my NES.
Should I swap the ROM pins only or the hc161 as I have talked before?
I'll post here the results.
Many thanks!!

The 74161 pins are not too important. What matters are the inputs and outputs being mapped correctly. If you swap them a certain way, the mapper behavior will not change; this is probably why the pirate cartridge has the 74161 wired differently.

The ROM pins are swapped. If you want to build a new cartridge using that ROM, you'll have to swap the ROM pins.

Tried the pin swap.
No luck
Does the game boots without the 74161?
Can you help me troubleshoot this?
I can post some pictures if needed...

If you can, make a diagram to show how you're connecting everything. It's much easier to follow a diagram than a bunch of photographs.

Is it really "pirate"? Or was it a homemade devcart at RARE?

I'm following this one http://elektropage.ru/cartmod/nes/nes_c ... matics.png
Is it correct?
I have checked and rechecked a lot of times...
Looks like I need some rest...
Maybe tomorrow I can throw some light on this!!

So... the ROM is sure fine. Is it?
I dumped it with an old PC motherboard and UniFlash.
Maybe I'm having trouble with the 74161. Does a normal cart at least boots without it?
Anyway, thanks for helping!!

Seems to be pirate.
It has a black plastic case, with an yellow label with a face and the word "Wizards" written on it.
On the back it had a label that is missig, I suppose it had the name of the game.
I'm just doing it for learning something new, since probably it's not worth the effort, and because I think throwing that at thrash doesn't feels right
Tomorrow I get a picture of the case and post, in case anyone wishes.
Last night I slept 3 AM trying to figure this one out. It's already 11:20 PM here...
Maybe if I had just throwed some superglue on the board I could have better results... who knows!!

Mostly. You want the AMROM configuration for this game. However, 74161 pin 5 doesn't matter for AMROM; you can connect it to VCC or GND instead of D2 and nothing will change. This is why the pirate cartridge has that pin connected to GND.

Also, the ROM pins are swapped, so if you follow that diagram's pin numbers to connect the ROM, it won't work. The cartridge edge D0 connection should go to 74161 pin 3 and ROM D0, but ROM D0 is pin 15 instead of pin 13.


You got the correct data out of it when you dumped it, but I don't know if it will work in the NES. Sometimes old EPROMs won't work fast enough for the NES to read them.


This game? No.

A picture of the cartridge case:


The back of the board:


The swapped stuff:
Data bus:


Address bus:


The case is sure asking for a good clean and relabel!
I have some more "caseless" cartridges, any idea of where to get pretty nice and cheap cases? Or even homebrewing them?

The data bus is sure swapped?
Data seems the same on the end of the file...
I'll try some more modifications, like the 74161 pin 5, maybe unswap the data bus and swap the 74161 pins.

The "new" board I'm using is from an old NROM cart. Had to "implant" the 74161.

I had put it under the PRG ROM, as you can see on the pic. Any suggestions for a better placement?

Just for curiosity I searched for the chip on the internet, to know how it works. It's a very nice programmable counter!!
Will work on it after lunch. Will post the results.

Wow, amazing... that cart, label, and board look absolutely Soviet-era.

Yes.

However, I just noticed I made a mistake with the address pins. The ROM's address pins are actually like this:

23 = A8 instead of A10
25 = A9 instead of A11
26 = A10 instead of A9
27 = A11 instead of A8

With this correction, the game should work.

Thanks! I had not time to take some tries today.
Real life things, family, kids, housekeeping... you know.
By the way, the kids just love to see this kind of "ancient" technology working and having fun with it!!
I I'll try the new mod tomorrow or during the week when I have some more spare time.

May I ask you Joe, how do you find this kind of swap? It seems compicated!! I really would like to learn.

@ccovell:
Nice to know it looks like Soviet era stuff.
As far as I know, this is a Brazilian cartridge, bought in an epoch when there was the "market reserve", a government law that made very difficult to import all things related to technology.
Instead of pushing the development of local technology, the law helped a lot to make piracy. Many big names of the industry made famiclones back on the day.
Did something like this happened in USSR too?
It's cool to learn a bit of history!

As usual, I'll post the results here.
Again, many thanks for helping!!

First, I used FARID's EPROM pin swapper to see if I could swap your pirate ROM to make it match the original ROM. (Actually, I should have swapped the original ROM to make it match the pirate ROM; that's why my earlier post was wrong!)

After you posted all of those pictures, I was able to compare the cartridge connector and ROM pinouts to the traces on the pirate PCB. That's how I noticed my mistake.

No luck
A13 and A14 seemed swapped too, fixed this and still no luck!
Looks like the best bet is to map the old board's pins to try to figure out what was changed.
I have scanned the old board, in case someone wants to help.
Any software recomendation to work these scans out?
Would be nice if I could combine both images , to make the mapping easier.

I do that with the GIMP when I'm tracing PCBs. Take one image, flip horizontally, use perspective transformation to align through-holes, set transparency to 50%.

Actually, I just traced it. Can you install GIMP / view XCFs? I'll PM it to you, if so...

Anyway, the revised PRG pinout is
I can't tell whether /ROMSEL is on pin 2 and A16 is on pin 24, or vice versa: the original PCB's traces clearly do as I said, but I see cut lines that make it look like this had been reworked.

Did it!!! Finally worked!!
Many thanks!!
Everything was fine, it was just A1 that had a bad solder joint.
One less cart in the thrash!!

Many thanks to everybody, specially Joe and lidnariq!!
I still want to learn how to trace the PCBs with Gimp, gotta try to do as lidnariq said!
Since I'm using Ubuntu. I already have Gimp installed.

Again, many thanks!!