MAMEWorld Forums - EmuChat - Re: Previously un-dumped Sega Hang-On EPROMs

oops, at the link then:
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"I wasn't sure whether to post this here or in the MAME section or in the Arcade - General section so if it's in the wrong section then feel free to move it.

I recently bought a Sega Hang-On board set from one of Gamingheaven's eBay auctions. It wasn't actually a full board set, just the CPU board and control board (no rom board (sprites) or sound board (Z80 + samples)).

It arrived a couple of weeks ago and I plugged it in to my Out Run cab just to see if it would power up and display anything as the listing did say that it was working, albeit with a fault. To my surprise it powered up fine and displayed everything except the sprites and obviously there was no sounds. But everything else was there, the road layer, the text layer, the 2 tile layers, all good. The intro sequence played, it went into attract and then the high score table scrolled up the screen at the end of attract.

So I unplugged it and packed it back up again and today decided to pull it out and dump the EPROMs to compare them with the known good sets in MAME (hangon and hangon1). Because I've only got the CPU and control boards it means I've only got the EPROMs for the main cpu (ic22, ic8, ic20 and ic6), the sub cpu (ic63 and ic51), the road (ic108), the tiles (ic38, ic23 and ic7) and the sprite zoom table (ic123).

After cleaning up the legs of all the EPROMs with a fibreglass pencil I dumped them all multiple times and confirmed that each dump was good by comparing in a hex editor. The SHA1/CRC checks for the road, the tiles and sprite zoom table EPROMs all agreed with the roms in the hangon/hangon1 sets but the main cpu and sub cpu checksums were all different.

So I loaded the game up MAME (it complained that the checksums were wrong but happily played the game) and immediately went into the service menu to do a memory test. Memory test showed good for all 6 main cpu/sub cpu EPROMs so this gave me confidence that my dumps were indeed good.

So I started a game with the easiest time settings via the dip switches and the first thing I noted was that you started a game with 90 seconds on the clock as opposed to the 75 seconds that you start a game with in the hangon/hangon1 sets on the easiest dip switch settings.

It then didn't take long to notice that the track layout is radically different to that of the hangon/hangon1 sets (actually the hangon/hangon1 sets have an identical track layout as all the track data is stored in the sub-cpu program and the sub-cpu program in those sets is identical).

The first stage is considerably easier on my undumped set than the hangon/hangon1 sets, there are less bends and the enemy bikes seem more docile and less inclined to try and ram you off the road!

Even though you start the game with more seconds (90/85/80/75 for normal/medium/hard/hardest on my un-dumped set versus 75/70/65/60 for hangon/hangon1) when you hit the first checkpoint you only get 55 seconds extra on the clock as opposed to 60 seconds extra when you hit the first checkpoint on hangon/hangon1.

I played through a bit further and I'm pretty sure that the rest of the stages are different too (although it's difficult to compare in your mind when you're switching back and forth between rom sets and then playing through the game!). The best way to compare I guess would be to record footage of both games and then play them back side-by-side.

The ending sequence is identical in both mine and the hangon/hangon1 sets.

Now because I only have the CPU and control boards it's impossible to know if the sprites that would have been on the sprite board EPROMs and the sound samples/Z80 code that would have been on the sound board are identical to those of the hangon/hangon1 sets but being as though the road/tiles/sprite zoom table all match then I'd go out on a limb and say the other EPROMs would probably also have matched and it's only the main cpu/sub cpu EPROMs that differ. As the chances of mating my board set up with its original sprite board/sound board are virtually nil then I guess we'll never really know the answer (unless someone else, somewhere in the world, has got an original 4-board set with the main cpu/sub cpu code the same as mine!).

So at this point I'm thinking that I might have an early version of Hang-On and started examining the boards closer. The sub cpu EPROMs are labelled with the original Sega labels but are numbered differently than the ones from the hangon/hangon1 set. Mine are labelled epr-6838 and epr-6839 whereas the hangon/hangon1 EPROMs are labelled epr-6919 and epr-6920.

Unfortunately the original labels are no longer on the main cpu EPROMs, they've been removed at some point in their life and replaced with black sticky tape. The board itself has been repaired at some point (looks like 15/8/1995 from the repair sticker) so it's impossible to say whether the original EPROMs were removed and replaced at that time or whether just the labels were removed and black tape stuck on or what! But the fact that these roms all show good in the memory test of the service menu makes me believe this is genuine Sega code.

There are lots of patch wires going all over the board, impossible to say whether this is as a result of the repair of whether it left the factory like this.

I examined the date codes on most of the chips and the latest I observed was 8519 so that puts that chip at somewhere in mid May 85. There is what looks like a date stamp at the bottom of the CPU board saying 850626. I know that Hang-On came out in '85 but I don't know when the first units arrived in the hands of arcade operators.

Anyway, I've taken a few (quite a lot actually!) blurry shots with my phone so that you can see the extent of the patch wires all over the board!

http://homepage.ntlworld.com/cmonkey/IMAG0511.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0512.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0515.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0516.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0517.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0518.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0520.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0519.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0521.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0522.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0523.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0524.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0525.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0526.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0527.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0528.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0529.jpg
http://homepage.ntlworld.com/cmonkey/IMAG0531.jpg

And here's some footage of the EPROMs running in MAME :-

http://www.youtube.com/watch?v=r5L8Hl8NVEc

Sorry for the dodgy camera work but it's not easy trying to play the game whilst holding a phone to record it at the same time!

And finally here's the actual board set running in my Out Run cab :-

http://www.youtube.com/watch?v=dKCxJeqno7w

I'd like to share the EPROMs with the rest of you but I'm unsure of the legality of sharing what it in effect copyrighted material. If someone tells me that it's OK to do so then I'll upload them to my webspace. I can't imagine Sega would be too annoyed with me for sharing 28 year old roms but I don't want to tempt fate.

It would be nice if these could be added to MAME as a third hangon set but I don't know whether they'd take them as they're not a full set of roms (obviously missing the sounds and sprites)."