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Naomi Cartridge Buffer Chips

stj said:
dump the eprom and compare it to the original then.
and dump a working one - just to validate your method - i assume your bankswitching with an adapter
Click to expand...
I'm an idiot. How the hell was I thinking a naomi game was gonna fit on a 32Mb eprom. Oh man.

So, how in the hell am I supposed to get the original eprom data without buying another 18 wheeler cart at $180?
 
Papalati said:
I'm an idiot. How the hell was I thinking a naomi game was gonna fit on a 32Mb eprom. Oh man.

So, how in the hell am I supposed to get the original eprom data without buying another 18 wheeler cart at $180?
Click to expand...
Oh man, I think I found the epr on archive. I'll get back to you @stj
 
if you cant find it, give me the game part number and i'll sort it
 
stj said:
if you cant find it, give me the game part number and i'll sort it
Click to expand...
Yup, I'm an idiot. I can't even burn an eprom properly. I tried using the information on this page to burn even a simple naomi 1 bios and couldn't do it.

I was using this site to try and help explain and walk through how to do the eproms: https://mousebitelabs.com/2019/09/02/27c322-160-programming-adapter/

It clearly didn't work or I misunderstood something, here are my steps i took just to do the bios file because the game epr didn't work either:

1. Take the bios file and use hjsplit to split it up into 512kb rom files
2. Using XGUPro set the IC chip to AM27C4096 and then set the settings for programming of the 27c322 ic and then I open the first rom file into the buffer.
3. Then, using the website I mention above, I set the dip switches to the first rom file position for 27c322 ic. So, all are set to off.
4. Then click Program. It programs and verifies it.
5. Open Rom 2 into the buffer.
6. Change the dip settings to the rom 2 setting shown on the link I used for reference. So that is 3 set to on.
7. Program and Verify
8. Open Rom 3 and repeat.
9. Open Rom 4 and repeat.
10. Only 4 Roms were created with HJSplit at 512kb so I'm done. Right?
11. Test if bios chip works and it doesn't.

I'm clearly missing a step not just for the bios but also for the epr rom since neither work. Was I supposed to clear the buffer after I programmed each one? I don't know.
 
@stj

I was wrong again. Nothing I burn is working. Not Naomi bios. Not the game rom. I’ve tried all versions I could find and it doesn’t work.

For the bios chips, when I split them there’s only like 4 roms. Am I supposed to fill the other 3 banks with blanks?

So this is for 840-0036C 18 Wheeler.

I also checked the first hex info for each bank of the original 18Wheeler ic22 and the order doesn’t even come close to the other versions dumped that I found on archive.org. The ones on archive more closely matched each other. They all say 18 wheeler info and have similar info but the original ic22 has 1 that is a different one. Talks about boot on bank 4.

Here’s some screenshots

Boot info on Bank 4
B7407656-9ABC-4320-927E-DDB73A97B456.jpeg
Comparisons of original ic22 to others found on archive.org
A424AD17-9036-4BAB-B245-4593D562AD0F.png
 
show your adapter and the instructions your following
 
stj said:
show your adapter and the instructions your following
Click to expand...
Its the same one I told you about before the TL886II Plus and I even updated to the latest software as you suggested.

burner.jpg


Here is the link again for the page where I got the info on how to bank switch. https://mousebitelabs.com/2017/09/14/how-to-make-a-snes-reproduction-cartridge/#step6b

A few posts up I wrote down the steps that I was doing. Split original epr file, then open Rom 1 set to Bank 0 and program/verify, then open rom 2 set to Bank 1 etc etc until the very last Rom and Bank 7.

The burner works fine as I have no issues burning Unibios chips when I need them.
 
skate323k137 said:
If you just need a 27c160 or 27c322 programmed, I can run one off for you.
Click to expand...
I've already bought some from you and if I'm gonna keep fixing these going down the road I need to be able to burn them for myself. Thanks though. I'm sure I'm missing something small.
 
Papalati said:
I even watched another guy burn one for a genesis cart and he did the same thing I did, but his worked. As far as bank switching process. Only thing different he did was byte swapping for some reason.
Click to expand...
Genesis ROMs are byte swapped on the cartridge compared to emulator ROMs in circulation. You have to do that (byte swap) if you want to burn a megadrive game from a downloaded ROM.
 
skate323k137 said:
Genesis ROMs are byte swapped on the cartridge compared to emulator ROMs in circulation. You have to do that (byte swap) if you want to burn a megadrive game from a downloaded ROM.
Click to expand...
So will a dumped emulator rom for naomi, for Flycast, work in a naomi if burned to an eprom? Or does it have to be a direct dump from the existing eprom to a new eprom for it to work?
 
Just pulled out my 866 with the 322 adapter to check if it works for me. I was using this guide: https://github.com/mafe72/27c160-tl866-adapter
to configure the dip settings and the 866 software. I used a random PGM rom for a 27C322. Split the rom into 8 x 512kb pieces with binman: https://www.jammarcade.net/programs/

Then programmed the 8 pices into the 322 using the dip settings in the link above. Then verified the eprom against the original file by reading it on an eprom programmer that natively supports the 322s. The dump was a match to the original file.

So things can go wrong when you split the files or with the dip settings. Hope this helps.
 
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nnap said:
Just pulled out my 866 with the 322 adapter to check if it works for me. I was using this guide: https://github.com/mafe72/27c160-tl866-adapter
to configure the dip settings and the 866 software. I used a random PGM rom for a 27C322. Split the rom into 8 x 512kb pieces with binman: https://www.jammarcade.net/programs/

Then programmed the 8 pices into the 322 using the dip settings in the link above. Then verified the eprom against the original file by reading it on an eprom programmer that natively supports the 322s. The dump was a match to the original file.

So things can go wrong when you split the files or with the dip settings. Hope this helps.
Click to expand...
The only thing different is the dip settings. Ugh. Of course its the dip settings. Ugh.
Thanks. I'll try it and let everyone know. Not sure why the other guy was using these as they are basically reversed...

dip settings.PNG
 
And just figured out why the bios wasn't working and wasn't going to work anyway with the wrong dip settings . Like I said, moron. I should've realized it when @skate323k137 offered both types of eproms.

Thanks everyone for getting me closer to my goal. You guys are the best!
 
Papalati said:
So will a dumped emulator rom for naomi, for Flycast, work in a naomi if burned to an eprom? Or does it have to be a direct dump from the existing eprom to a new eprom for it to work?
Click to expand...
For the EPROM on the cart itself, with NAOMI stuff, the NAOMI ROMs from MAME should have a file like epr_whatever.ic22 that you can burn directly and unmodified to the right chip. If the file is 2MB it's intended for 27c160 and 4MB is for a 27c322
 
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