How can I learn about proprietary hardware communication?

Question

If I have two pieces of hardware (say a PC with a custom ISA or PCI card connected to a piece of hardware using some crazy cable) and want to see as much as possible about the conversations between them, how would I go about doing so? In particular, I'm interested in old scientific hardware connected to Windows PCs (old and new). Any references would be appreciated.

I'm not interested in thieving anyone's IP. I'm a scientific programmer in academia and we have to deal with orphan hardware all the time. It really sucks to have to throw away perfectly good hardware because the company went out of business and their software runs on Windows 3.1 and uses a proprietary ISA card. It would just be nice to save some of that stuff (some things are expensive or impossible to replace) by writing my own code using a modern data acquisition card and spliced cable.

Answer 1

I would recommend googling for the specs...

Unfortunately, the most likely solution is that you will need to reverse engineer a protocol by putting something (your data acquisition card perhaps?) between the proprietary card and the device.

Once you figure out the communication protocol (serial IO if you are very lucky) you can begin documenting the data stream and work from there.

(Just my $0.02 I have NO experience in these matters.)

Answer 2

You probably want a signal analyzer or something similar, but...

If the device uses a proprietary protocol to communicate, you really have your work cut out for you. I would seriously consider just keeping an old machine around with the original interface card and software until you can afford to replace the hardware.

Answer 3

If possible/affordable, you could use a PCI or ISA bus analyzer to figure out how to communicate with the proprietary interface card. Then you would be able to create a device driver for more modern operating systems using more modern hardware (possibly with the addition of a PCI to ISA bridge).