Unknown 68k Board

[appleIImidi]

Other than finding one for sale on eBay for a whopping 125 dollars, I can't find any info on this board. I think I paid like 10 bucks for it years back, mainly for the memory chips that I thought I may need at some point. I attached the ROM files as a zip, because apparently you can't upload files without extensions on this forum, and zip is the only compressed file allowed for some reason. It did cut the 32k worth of files almost in half though, should download quickly, haha. I couldn't find anything useful in them.

 

[twolazy]

Given IGS was popular in the arcade scene, my guess is some sort of Arcade PCB.

 

[skate323k137]

Given IGS was popular in the arcade scene, my guess is some sort of Arcade PCB.

Very true, IGS was huge in China and Taiwain etc.

MAME has a tool to identify if a ROM you dumped belongs to an existing game, you can try it, or when I get a moment I will have a closer look.

KI4SWY's (Hamster's) Web based RomIdent!

romident.coinopflorida.com

Edit: looking at the connectors I would wager its an add on board, since it doesn't have a JAMMA edge connector or JVS connections visible typical of a main PCB. Just an educated guess.

 

[commodorejohn]

I kinda wondered about something arcade-y with the combination of 68k and Z80, but I don't see anything that seems plausible as a sound source, the display controller is just a 6845, and there's a floppy controller and UARTs on it. Gotta be some kind of workstation board.

 

[Al Kossow]

It is the board for an IBM 3812 laser printer
You can see "IBM3812" in the first 16 bytes of the merged eproms

IBM 6192421 3812 MODEL II IGS 1M BOARD | eBay

Find many great new & used options and get the best deals for IBM 6192421 3812 MODEL II IGS 1M BOARD at the best online prices at eBay! Free shipping for many products!

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IBM 3812-002 Laser Printer - AS IS

Find IBM 3812-002 Laser Printer - AS IS, Surplus Store at RecycledGoods.com | Ventura California | (888) 488-6550 Call Toll Free

www.recycledgoods.com

 

[twolazy]

Oh wow good find Al, got sidetracked and didnt throw the dumps into a hex editor yet.

Wonder why IBM contracted IGS to create pcbs instead of doing it in house.

 

[Chuck(G)]

Got some neat parts worth scavenging, provided you opt for local pickup at a reduced "make offer" price. Given the age of the thing, it's unlikely to find real-world application. 68Ks weren't uncommon in 1980s laser printers, since I believe that postscript was originally written for that platform. Witness Apple's LaserWriter.

 

[Eudimorphodon]

IBM 3812

I was going to ask why a printer would have a floppy controller chip on it but, low and behold, said printer apparently actually had a 1.2mb floppy drive in it according to these specs.

IBM Documentation

IBM Documentation.

www.ibm.com

The presence of a 6845 is also “interesting”, but considering how laser printers work it may well be perfectly logical to use a CRTC to control the scanning.

combination of 68k and Z80

The Zilog part with the Z80-ish looking number is actually an SCC UART.

 

[appleIImidi]

Thanks guys. I won't feel bad removing most of the chips and scrapping the board now.

I have no nostalgia for old laser printers. I'm a dot matrix kind of guy.

I've never tried merging ROMs before, I'll have to look into that.

 

[twolazy]

Got some neat parts worth scavenging, provided you opt for local pickup at a reduced "make offer" price. Given the age of the thing, it's unlikely to find real-world application. 68Ks weren't uncommon in 1980s laser printers, since I believe that postscript was originally written for that platform. Witness Apple's LaserWriter.

It was! I remember my old QMS laser printer, made in 87? Basically same as an early apple Laser printer (seriously same company designed it i believe), and was postscript and PC compatible. But it was sold BEFORE the Apple version. It was 68k based, 1mb ram (Eventually did upgrade it to 2mb). If I recall correctly, were the first as well to use/create Postscript, think with Apple? I had the QMS 300dpi before the Apple one came out and it had postscript. Man the lights would dim when that printed! lol

I used that printer well into the 90s (think 96/97?) creating vector art ( fonts / diagrams / lineart), can still smell the ink and ozone thinking about it. Then I got a nice Lexmark 1200dpi, then Xerox Phazer Color printer...

 

[skate323k137]

Thanks guys. I won't feel bad removing most of the chips and scrapping the board now.

I have no nostalgia for old laser printers. I'm a dot matrix kind of guy.

I've never tried merging ROMs before, I'll have to look into that.

If they're interleaved I have used a python script before, but I'm sure there are infinite ways to do this.

Coincidentally it was an IGS game I did this on.

Conversion (upgrade) PGM Puzzli2 to Super

I decided to look into upgrading my puzzli 2 to super, and was able to do it easily. In the MAME dumps, Puzzli2 has a 16mbit program rom, super had 2x 4mbit. Looking into v100.u5 (normal ver) I found the last half blank. That solved the mystery of size differences. Both games have 8mbit "real"...

www.arcade-projects.com

 

[commodorejohn]

The presence of a 6845 is also “interesting”, but considering how laser printers work it may well be perfectly logical to use a CRTC to control the scanning.

Yaknow, I'd never thought about that before now, but yeah, I guess that does seem logical.

 

[traveler_aa5]

Oh wow good find Al, got sidetracked and didnt throw the dumps into a hex editor yet.

Wonder why IBM contracted IGS to create pcbs instead of doing it in house.

IBM didn't make the 3812. It was built by an outside vendor. It was a LED printer, not a laser printer. IBM got sued by some guy who had a patent on a 2 row LED printhead. The 3812 had a one row LED, but the SELFOC lens looked like two rows, and lost the suit. I was tasked with putting a laser printhead in the 3812. I had to take 2 serial lines in and combining into 1 for the printhead. I used the biggest FIFO's I could find, and got it to work. The laser printhead was rotating the wrong way, so all printing came out backwards. But it was enough to convince the patent holder to be reasonable on his licensing requests.