Full spectrum of issues

So I'm putting this in the INBOX.EXE because I have a multitude of questions that fit in many categories. I'm also hoping that with the attention drawn to Inbox, I can get help for everything in one place. That and this is going to take some old school help I think. Mods, feel free to move this if you think there's a better place for it.

I'm using a dual computer system to control automated chain hoists. The system was deisgned in 1996 and with the exception of a few hot key additions, the software has remained completely unchanged since then. It came out the door great, blew the industry away and when it runs, it's bullet proof.

However I'm at the point where getting them to run is the issue. The software is running on German DOS 6.22. It's all proprietary, and I've been given everything save for the source code.

There is an "Operating" Computer and a "Server" computer that work together to make the hoists move.

Bringing new life to the Operating computers has proven fairly easy. We've been using the iBase MB800V-R motherboards which clock in at about 2.77GHz and everything is fine.

I do not however have an answer for motherboards for the servers. The iBase MB700 was a great alternative to the multitude of motherboards that exist among the 12 pairs of systems (There's everything from Asus P5A-B to PM9800s to PCISA Bus Board combos. Literally, whatever was laying around for them at the time is what they built it with.) However, that board is no longer in production.

The server computers can't run at more than 1GHz, otherwise the closed networking fails. The server has an ISA Interbus Card for communicating with the hoists, an ISA 10/100 Network card, a PCI Watchdog Timer card and an AGP Video Card.

Yes, ISA. Interbus cards run between $1,000 and $2,000 dollars. I have 12 of them, and replacing them with a newer version of Etherbus isn't much of an option, as it would render all the software useless.

At the moment, I'm unable to switch to PCI Network cards, as the networking software, LANSOFT, does not support them. I've tried googling my way to the PCI supported version, but I'm coming up empty handed. Is it possible to rewrite the lansoft program to support PCI Express?

Does anyone know of a good motherboard that has 2x ISA, 2x PCI and 1x AGP slot and can be downclocked to under 1GHz? I'm going to need at least 24 of them.

Any thoughts on getting the Lansoft program to work with PCI Network cards? I can find motherboards with 1x ISA, 4x PCI and 1x AGP/ Built In Graphics a lot easier. Getting rid of the ISA Network cards would make this entire endeavor easier.

And before you ask, yes, I've asked the original manufacturer to update this. Their answer is that the system is perfect just the way it is. They understand that I want to modernize it to a degree, and have told me to go for it, but that they wouldn't be able to help outside of everything they've provided so far.

"Why not just write new software?" you may ask. I'm getting there. But before I can turn my attention to that, I have to stabilize the systems we have. I need a standard across the map so that when I get a call for support, I don't have to remember 19 different bios layouts, 12 different internal wiring versions, etc.

So with writing new software, does anyone have any advice where to start. Yes, I have no idea what I'm doing. I know that I have an Interbus based communication system. I know that the Interbus hardware is absolutely great. We have replaced one IBS card since 1996 and I have several more spares I grabbed off Ebay.

So do I jump head first into learning C/+/# and then attempt to communicate with pieces of hardware? If I can stabilize the existing system, I'll stand a better chance of moving to EtherBus or some other derivative. Then I think life would be easier because instead of using an outdated communication protocol, I could be based in TCP/IP communication. Basically I'm asking are any of you out here involved in that kind of programming from day to day and have pointers.

Yes, I've looked to industrial automation companies to write new software for me. However I'm having a hard time getting it through their heads that I can tell them EXACTLY how it all functions together. I just need someone to write a UI and duplicate the IBS communications. Everyone wants to jump off a million dollar cliff that other companies have tried, and failed. It can be done, expecially given my extensive knowledge of the system. It's just a matter of picking a communication protocol and going after it.

So, anyone have any answers?

TL;DR: I wrote the shortest version I could, read it.