Undocumented Apple IIgs ROM Found

17 posts / 0 new
Last post
Offline
Last seen: 10 months 6 days ago
Joined: Sep 13 2023 - 15:59
Posts: 5
Undocumented Apple IIgs ROM Found

Hello there- found this forum while searching around. I recently purchased a GS logic board, still sealed in its electrostatic plastic. It seems to be a stealth board, actually. Anyway, I noticed the ROM chip has an IC number that doesn't match anything I've found online. ROM0 is 342-0077-A, ROM1 is 342-0077-B, and the ROM3 chips have their own separate set of numbers. Well, this chip happens to be 342-0077-C. If "9235" is the datestamp of the chip, then it would have been manufactured in 1992, after the ROM3 was released. I am guessing it is either a second rev of ROM1, or possibly some kind of updated "ROM 1.5" perhaps with other fixes, as a replacement part for ROM1 machines. This is a service item, so this was manufactured specifically as a replacement part. I've attached some photos, would appreciate any information.

Offline
Last seen: 2 months 3 weeks ago
Joined: Jul 5 2018 - 09:44
Posts: 2587
What is critical is if you

What is critical is if you can find a dump of the contents of the chip so it can be compared to the other versions to verify if it does include enhancements or bug fixes.  If it does, it could be of tremendous value to IIgs owners.

 

Offline
Last seen: 9 months 3 weeks ago
Joined: Sep 14 2023 - 04:49
Posts: 2
Interested...

Hello, I am interested in buying it, the battery having eaten my motherboard...
I am in France, but I can (and will) make a dump and post it later for people able to compare contents (I can post other versions I do have yet.!)
Let me know if you want to sell it.

My best

Offline
Last seen: 2 hours 26 min ago
Joined: Feb 27 2021 - 18:59
Posts: 554
ROM1?

You have a ROM1 GS with battery damage? That mostly affects ROM3 motherboards with Maxell snap-in batteries.

The ROM0 and ROM1 used soldered, leaded batteries, which were not as notorious for leaking.

Offline
Last seen: 10 months 6 days ago
Joined: Sep 13 2023 - 15:59
Posts: 5
I'd like to find out more

I'd like to find out more about the ROM, if there is any info out there, before breaking the seal. I'd hope someone's seen one or even dumped one before. 

Offline
Last seen: 10 months 6 days ago
Joined: Feb 28 2010 - 12:40
Posts: 4
An answer...

I asked Jimmy Mensch, a former Apple employee who has worked on the IIgs, on Facebook, and he said:"I can think of two possibilities, most likely apple ram out of the rom chips and had to send a new mask to the chip mfg as the rev b had been out of production for a while by then. If they had to recreate that then they might have rolled the part number. I don’t recall any rom 01 work after the rev b. If they dump it they may find that it is identical or possibly only different by copyright dates on the ROM. The only othe thing I can think is a international version… but that is VERY unlikely as it would be more prevalent. Probably just a very late in the game service spare run. It would be easy enough to find out by just dumping the ROM"You should open it, and dump the ROM. I'd be happy to host it at http://mirrors.apple2.org.za/Apple%20II%20Documentation%20Project/Computers/Apple%20II/Apple%20IIGS/ROM%20Images/

 

Thank you,

Antoine

 

 

Offline
Last seen: 1 day 6 hours ago
Joined: Jun 29 2018 - 16:55
Posts: 586
Toinet wrote:I asked Jimmy
Toinet wrote:

I asked Jimmy Mensch, a former Apple employee who has worked on the IIgs, on Facebook, and he said:"I can think of two possibilities, most likely apple ram out of the rom chips and had to send a new mask to the chip mfg as the rev b had been out of production for a while by then. If they had to recreate that then they might have rolled the part number. I don’t recall any rom 01 work a

Antoine, 

 

Good to see you here. I have dumped a Laser128 (original ver) ROM which wasn't archived anywhere else, I would love to see it in your mirror along side these if you can, as the original revision hardware seems unable to run on 4.x or newer. 

http://mirrors.apple2.org.za/Apple%20II%20Documentation%20Project/Computers/LASER/LASER%20128/ROM%20Images/

See https://www.applefritter.com/content/laser-128-rom-dump-rom-ver-35

 

Sorry OP for the side-jack, I hope you dump these ROMs and find out :) 

Cheers,

Alex

Offline
Last seen: 10 months 6 days ago
Joined: Feb 28 2010 - 12:40
Posts: 4
Hi Alex,Thank you, your Laser

Hi Alex,

Thank you, your Laser 128 ROM v3.5 is now available @ http://mirrors.apple2.org.za/Apple%20II%20Documentation%20Project/Computers/LASER/LASER%20128/ROM%20Images/

 

Antoine

Offline
Last seen: 1 day 11 hours ago
Joined: May 31 2022 - 18:18
Posts: 302
WTF, can you get a better

WTF, can you get a better image of the VGC? It looks like it's version D which would be at least 1987 which would be strange.

 

 

I'm not sure why you say you think this is a stealth board, is that because it's a ROM01 with the //e power and keybaord connectors?If you're not aware... there were quite a few GSes in GS case that had boards with this configuraiton. Wasn't a ton, but also was far more than 10. 

 

 

 

 

There are a few thoughts on why, but one being they had stock of the upgrade boards when they ran out of inventory of the regular boards. If that was the case, the easiest way to keep the lines running would be to pull these boards from a shelf and run. There's so many odd things that happen in manufacturing, could also explain this "odd" ROM because if there was an inventory problmem they would find anything else that works, and since it's a different part from a different supplier it would have to get a unique part nubmer. Gotta read the part to answer the quesion. My guess would be this is nothing different.

 

 

 

 

 

The only time I'm aware of, that new part number wasn't needed was with assembled parts like power supplies, keyboard assembly, etc. As long as it was a plug and play replacement they could slap the same part number> This was common with different supplies (ASTEC, Dynacomp, etc). But with ICs they can't do the same. Even if you replace a 64K part with a 128K part they should have unique part numbers and the 128K part would have 2 copies of the same 64K image.  Most people would be surprised how crazy a factory floor is. Even today it's nuts, 30 years ago in computer manufacturing chaos was the norm. Priority #1 was get product out the door, didn't matter how.

 

 

 

 

 

 

HTF do insert a line break? I hate this editor...

Offline
Last seen: 1 day 11 hours ago
Joined: May 31 2022 - 18:18
Posts: 302
I took a closer look and I

I took a closer look and I think I may have an answer, and if you pull the ROM and read it, it should be the exact same as the B ROM.

 What I think happened is the B (and A) ROMS were manufactured by Toshiba. At some point there was likely a problem with Toshiba's supply and Apple was able to get parts from Hitachi. So, as mentioned above when that happens A new part (-Revision counts ad different) 

 342-0077B  is the Toshiba part ROM01

 342-0077C is the Hitachi part ROM01

 At least that's my guess. I'd love for ROM to be pulled and read so we can have an answer!!

Offline
Last seen: 1 day 11 hours ago
Joined: May 31 2022 - 18:18
Posts: 302
WTF, Can you read the ROM?

WTF, Can you read the ROM? Assuming you're willing to open the bag...If not, I could do it if you send it to me or if you happen to be near by I can bring the tools to you.  You can also check me out on the facebook group, I basically responded to Antoine's post there saying the same there.

Offline
Last seen: 10 months 6 days ago
Joined: Sep 13 2023 - 15:59
Posts: 5
IMG_9255.png
Yeah the VGC is rev D as well and if I'm reading the correct numbers as the date stamp, is 1992. 
Offline
Last seen: 10 months 6 days ago
Joined: Sep 13 2023 - 15:59
Posts: 5
This old post I found also
Offline
Last seen: 1 day 11 hours ago
Joined: May 31 2022 - 18:18
Posts: 302
Whiskey Tango Foxtrot wrote
Whiskey Tango Foxtrot wrote:

This old post I found also shows a rev D

 

https://www.instructables.com/Replace-an-Apple-IIGS-clock-battery/

Thanks that's interseting, I'm not sure I've see a D before.

 

I also notice a VLSI 65816 on that board and when I tried to check the ROM, no matter how many times I wiped my screen the dust would not disappear. LOL, I can't believe I really wiped my screen!

 

It did have the //e connectors too and if, as you say, it's a 1992 part then you really have to wonder. Because if it was manufactured that late did that mean Apple was still selling ROM01 systems alongside the ROM03 or more likely someone had a problem with their original ROM01 system and service grabbed a old stock and upgraded that part. Service notes from that time may provide some clues but  I don't have those. 

Offline
Last seen: 2 hours 26 min ago
Joined: Feb 27 2021 - 18:59
Posts: 554
long shadow of the "stealth" IIgs

Since only the ROM1 supported the Apple IIe keyboard connectors, it was the only option to support warranty repairs for "stealth" IIgs customers. That could require continuing manufacture of the ROM1 board, even as late as 1992.

Consider that the ROM3 IIgs was introduced in 1989, that new units might stay in the sales channel for a long time, and that some customers purchased extended warranties. Some computers stay supported for over a decade; 3 years from 1989–1992 isn't that long.

Offline
Last seen: 10 months 6 days ago
Joined: Sep 13 2023 - 15:59
Posts: 5
French Tech wrote: Hello, I
French Tech wrote: Hello, I am interested in buying it, the battery having eaten my motherboard... I am in France, but I can (and will) make a dump and post it later for people able to compare contents (I can post other versions I do have yet.!) Let me know if you want to sell it. My best

Sure I'd consider selling it. DM me what you think is a fair offer. Shipping to France won't be cheap though. 

Offline
Last seen: 1 day 11 hours ago
Joined: May 31 2022 - 18:18
Posts: 302
Want to check if there are

Want to check if there are any updates, did you sell it? 

Has the ROM been read? The suspense is killing me. =)

Log in or register to post comments