[GUIDE] Make a Reprogrammable Genesis Cart

[OtakuNami]

Homebrews/repros made in china are better

[icemanxp300]

Jazz you ever do multi carts? I read simply pasting the code of a game on the end of another allows you to have 2 games that will toggle via reset. So as using 2 1MB games to make 1 multi 2MB game. I tried it and it did not work. I copied the hex code of game 2 and pasted at the end of game 1, and saved file. I then opened the file, byte swapped it, programmed it, and it only plays game 1. Reset just resets to Game 1.

[Jazzmarazz]

Jazz you ever do multi carts? I read simply pasting the code of a game on the end of another allows you to have 2 games that will toggle via reset. So as using 2 1MB games to make 1 multi 2MB game. I tried it and it did not work. I copied the hex code of game 2 and pasted at the end of game 1, and saved file. I then opened the file, byte swapped it, programmed it, and it only plays game 1. Reset just resets to Game 1.

That will not work. See my second post in this thread. The tutorial is old not finished though.

[icemanxp300]

I did not read this info from this thread. This statement was made in a youtube comment by someone.

"FYI if you take two bin files (post byte swap) and merge them into one bin file and write it, you get a two for one game that splits based on the RESET button.. e.g.: instead of filling a 2 meg with FFFFF you can flash two 1 meg games, hit RESET and it will go to game #2, hit again, game #1."

[DeeP771043]

Hi,

I ve read almost everything it this thread (not that I understand everything, but Im trying). I ve learned how to make common non-save games of different sizes and some battery-save games too.

What I'm trying to do now is to write some LARGE hacked ROM on to cartridge (It is Hacked UMK3 rom, so no save). It's working on my friend's flashcart on MD1 well. The total ROM-size is 6103KB (6.1 MB), So I guessed that I should split it like Jazz said earlier(Using H). So I got two *.bin file (4MB and 2.07MB).

The PCB that Im trying to use is from japanese SHINING FORCE I. As I see it it uses TWO Sega Roms on it. (When I first saw it I thought AHA!!) How do you think will it work if I just solder two 27C322's(4+2.07) on it? Will it work? And then what is the order in which I should solder them, which one's where?

The pic of the PCB - https://www.dropbox.com/s/fhzqgw3x5t...85655.jpg?dl=0 , https://www.dropbox.com/s/xaxarxrmg1...85702.jpg?dl=0



PS. Jeez... Sorry for such stupid questions...

[CeeJaySWE]

A heads up to all the young players. M27C4002 is not equivalent to M27C400 even though it seams like it spec wise. it's wired up completely different.
Learn from my mistakes, people!

[borracho2x]

Thanks for the tutorial, I made my firts repros...
Any way to make a multirom with 27c160 with 2 games of 1MB?
Use 1MB bank switch

[xIceMan]

I just recently saw this topic: https://www.epforums.org/showthread....t-with-a-TL866

if anyone needs such a 16 bit adapter for the TL866, let me know. I have a few (I think 6) laying around I could sell for a fair price.

[_psx_]

have been away for awhile from this repro stuff, today i burned the SONIC3C to an 27c322 eprom put in my test cart everything works! great i thought so i soldered it to a sega board whit sram, pulled leg 32 upp and solderd a jumper wire to the 74hc00 leg 4, now it only gives me the licensed by sega then black screen,


second tought i have a few boards that have two 74hc00 where should i connect the jumper wire from leg 32 on the 27c322? same question fot the ea boards that use a 74ls138.


i have noticed some difference on the boards when i have followed the traces whit a multimeter. do you have any pictures of a repro 4mb whit sram? was think so i can follow the traces on them since there can be diffrent layouts.

regards /Tomas

[KorvasTerindar]

Hey everyone, I've got a huge number of old genesis sports games (like, 25 or so) from lots that I bought for other games. Nobody wants the sports games, I don't want the sports games. I want to make the sports games into games people do want or that I want but unfortunately, I'm a complete novice when it comes to identifying the types of rom chips, or identifying why boards have more than one chip soldered to it, or whatever. I've seen no clear tutorial on what to do with boards with two chips and a battery and it seems as though most of the sports games fall into that category. I could really use some help.

[balaganja]

Hi all, wonderful tutorial
I've got the Top3000 programmer and so far succeeded in burning 1meg games only
When I try something larger, I get black screens all the time. I am aware of eprom types and use the appropriate one (160 or 322) and use carts of 4megs.
I'm kinda lost here. According to the tutorial, it seems pretty easy.
Any help will be appreciated

[RogerCM]

Congratulations excellent topic

[shion arita]

I'm having some trouble with my reproduction and want to see if anyone can help troubleshooting.

I'm trying to make Warsong/Langrisser (512k/4Megabit rom w/ SRAM save) using an NBA Live 95 cartridge (2048k/16Megabit rom w/ SRAM save). I used a 27c160 EPROM, and programmed all 4 banks with the Warsong rom file (probably unneccessary but whatever). I soldered it in and I only get a black screen; no license text or anything. I did byteswap the rom file.

Does anyone have an idea of what could be the issue?

Edit: I found the problem(s). First, in my breadboard adapter from the 27c160 to the TL866 two wires were switched. For the record, if Query or Address pins are switched, the chip will appear to program and verify correctly, because all the data will be on the chip, albeit in an incorrect order. But the incorrect wiring will correctly read the incorrect order because it was what was used to program it.

The second problem was that my test cart was using these kind of female headers, which for some reason was not making good contact with the chip legs on the eprom. I resolved this by using a breadboard and jumper wires (which have longer legs). This shouldn't be a problem when I solder it down for real.

However, one issue remains; apparently, NBA Live 96 (which is what the test cart is; 95 is what I soldered the first attempt directly to) does not have the correct amount of SRAM, and i get an error saying as such when I try to save. 95 probably has the same problem. I've looked for a comprehensive list of which games have how much SRAM, like I've been able to find about NES and SNES games that I've made repros of in the past, but I haven't been able to find this info for genesis. Does anyone know where I could find this information?