Troubleshooting Northgate OmniMac Ultra

[boulder]

I had the fortune of recently finding a Northgate OmniMac Ultra keyboard (The Mac variant of the OmniKey Ultra) for $5 at a thrift shop. However I've had no luck getting it to work, or even light up for that matter. I really don't want to have to scrap this thing for parts, so I'm hoping someone around here might be able to give me some insight into what the problem is that I'm having. I've tried using straight PS/2 to PS/2, as well as PS/2 with a converter to USB. Neither of which worked. I have a teensy and the resources to mod this thing, but before I do I want to make sure it's actually kaput.

What I'm thinking may or may not be the problem:
1. Is now fried potato. I've been reading a little bit about ADB  (Apple Desktop Bus), and I've heard vague references here an there to hot-swapping being dangerous, and an explicit instance of an OmniMac or some other old keyboard being fried after plugging it into an Apple II or something. IDK. Either way, this might be what happened.

2. My dip switch configuration is incorrect. While I've been able to find OmniKey Ultra user manuals, I haven't been able to find any specific to the OmniMac. My assumption was that the only difference between the OmniMac and the OmniKey was the inclusion of ADB ports on the back. However, my inability to use the PS/2 port on the back makes me think the dip switch configurations might be different.

3. Are OmniMac ultra's actually (by default) compatible with modern machines? I assume they are, but I'm unsure seeing as there's very few resources I've found for properly configuring one of these things

Anyway, please share your thoughts on what I might do here. I would really like to use this keyboard.

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edit:

What I'm primarily looking for now is if anyone has had any experience with this keyboard or a similar one and actually knows how to configure the dip switches. Or if anyone can confirm that the PS/2 port is actually intended for what we're assuming it's intended for here. Or just a goddamn manual

[Tactile]

ADB is not PS/2. It sounds like you're plugging this into a PS/2 port & that won't work. Nor will a PS/2 to USB adapter work.

The Griffin iMate is an adapter which is made for this & there might be others.

[merlin64]

One thing I generally do, is open up the keyboard and give it a thorough cleaning.

If your cable is secured to the circuit board via a connector, try finding a ps/2 cable you know that works and trying that. It might be a broken cable too.

Take 90% isopropyl alcohol and a tooth brush and scrub that circuit board clean. Sometimes oxidization can cause issues.

I'd also check for any broken solder joints. If you have a multimeter check the traces on the board as well.

Beyond that, it might be a fried controller.

[merlin64]

I assumed it was PS/2 as well, my fault.

If it's ADB, I would look into getting the iGriffin adb to usb converter. Unsure how it works with non Apple keyboards though.

Another option is to look into the TMK firmware and build your own converter using a Teensy 2.0.

[boulder]

ADB is not PS/2. It sounds like you're plugging this into a PS/2 port & that won't work. Nor will a PS/2 to USB adapter work.

Heh, I'm not really sure where you got the idea that I thought ADB was the same as PS/2.

The keyboard doesn't exclusively have ADB ports. From what little I've found on the keyboard, it sounds like it was originally intended to be compatible with both Apple and non-apple machines. If you look at the layout of the rear keyboard ports, there's a PS/2 port in the same position as the port on the OmniKey Ultra, with two ADB ports on either side of it which seems to point to one of the ports being an alternate to the PS/2, and the other being intended for an ADB mouse.

Why will a PS/2 to USB adapter not work? I've seen this mentioned here and there, but I haven't seen any particularly clear explanations as to why.

[merlin64]

The ps/2 to usb adapter may indeed fit, but the reason it usually works is because the micro controller inside the keyboard supports USB.

Not all PS/2 keyboards back then support USB.

[boulder]

One thing I generally do, is open up the keyboard and give it a thorough cleaning.

If your cable is secured to the circuit board via a connector, try finding a ps/2 cable you know that works and trying that. It might be a broken cable too.

Take 90% isopropyl alcohol and a tooth brush and scrub that circuit board clean. Sometimes oxidization can cause issues.

I'd also check for any broken solder joints. If you have a multimeter check the traces on the board as well.

Beyond that, it might be a fried controller.

Yeah, I was going to grab a multimeter and check it out, but I just haven't gotten around to taking this thing apart.
I didn't even consider cleaning off oxidation, that's a good idea.

[boulder]

The ps/2 to usb adapter may indeed fit, but the reason it usually works is because the micro controller inside the keyboard supports USB.

Not all PS/2 keyboards back then support USB.

I see

I assumed it was PS/2 as well, my fault.

If it's ADB, I would look into getting the iGriffin adb to usb converter. Unsure how it works with non Apple keyboards though.

Another option is to look into the TMK firmware and build your own converter using a Teensy 2.0.

Yeah, I saw that iGriffin, but it's basically the price of a keyboard, so I'm not even gonna bother with it. Too damn much. Probably gonna just use a teensy and do it.

[boulder]

I guess what I'm primarily looking for now is if anyone has had any experience with this keyboard or a similar one and actually knows how to configure the dip switches. Or if anyone can confirm that the PS/2 port is actually intended for what we're assuming it's intended for here.

[fohat.digs]

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[boulder]

I had no idea that PS/2-to-ADB compatibility could be as simple as a little DIP switch juggling!

Did you even read the other replies? I understand the difference between ADB and PS/2. What I don't understand is if the dip switch configurations differ from the OmniKey Ultra, and if they perhaps enable the PS/2 port as opposed to the ADB ports.

[chyros]

I had no idea that PS/2-to-ADB compatibility could be as simple as a little DIP switch juggling!

Would it really though? If it were, why make a separate Mac version of a keyboard? Oo

[boulder]

Photos would be a huge help.

Connecting the proper cables to the proper sockets is always a requirement.

I had no idea that PS/2-to-ADB compatibility could be as simple as a little DIP switch juggling!

Here's the three ports that we're talking about.



From a post in another thread (https://geekhack.org/index.php?topic=7837.0), I've gathered that the two ADB ports are in parallel, and I've seen references on one other site saying that it was for a keyboard and mouse connection, but I haven't found any explanation on configuring it. And I can't find a OmniMac manual that says how to configure it, or if it's any different from the OmniKey configuration.

[fohat.digs]

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[boulder]

Did you even read the other replies?

Yes, I read the other replies.

Until you find out what the preferred configuration was supposed to be, it will all be guesswork.

My understanding (and I am not any kind of Apple guy) was that ADB and PS/2 are wildly different and essentially incompatible.

And I have had quite a few Northgates but none of them had anything Apple-related about them.

You're right, ADB and PS/2 are wildly different and incompatible, which I believe might be the reason why they included separate ADB and PS/2 ports on the keyboard. ADB and PS/2 compatibility aren't factoring into this at all. There is no PS/2 cable that I'm trying to convert/connect to an ADB port.

From the thread I linked above, there are apparently model ATs floating around made from surplus OmniMac parts with 4 PIN MINIDIN (ADB) and 6 PIN MINIDIN connectors on the back. Apparently the schematics don't show what the ADB ports are for, probably because the keyboards weren't meant to be compatible with Macs anymore.

[boulder]

You can also see in the picture above, there are three ports on the back of the keyboard, two of which are ADB, and one of which is PS/2

[fohat.digs]

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[boulder]

there are three ports on the back of the keyboard, two of which are ADB, and one of which is PS/2

Just taking a wild guess, I wonder if they were giving you an opportunity to plug in a PS/2 mouse.

you're just trolling at this point.
Do you want me to apologize because you didn't understand the problem after I clearly laid it out?

[fohat.digs]

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[boulder]

lol, it's literally just you

[fohat.digs]

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[boulder]

Hence the plethora of working solutions.

so the guy who doesn't understand what's wrong is saying there isn't a working solution in this thread?

[JimByr]

You might try contacting Bob Tibbetts, the known expert on Northgate keyboards. He seems to prefer a phone call.

http://www.northgate-keyboard-repair.com/

He might have the settings for the Mac version.