HP-IL protocol description ?

[Pavel Korensky]

Hello,

I would like to know, if it is possible to find the description of the HP-IL protocol (voltage levels, frames, commands etc.) somewhere on the Internet.

[Vieira, Luiz C. (Brazil)]

Hewlett Packard Journal, January 1983 issue, brings a good HPIL description, but it is just good literature. It has four articles that describe the HPIL itself, explain its interconnection system, show the electronics for it and describe its IC. By reading it you will get to the philosophy of the HPIL System, but I think some more is needed to get into its protocol. Instead, it's a good starting point.

I'm not sure this issue is available at the HP site or even here at HP Museum (you should check at the CD Pack), but I can send you the scanned images, if you need. Send me an e-mail.

[Tony Duell]

Not on the Internet (AFAIK), but HP did publish a manual giving a complete description of HPIL. It's called something like the 'HPIL Specification'. I think it's on the MoHPC CD-ROMs, but not being able to view .pdf files, I can't be certain.

[Holger Veit]

There is an old book by Kane & Ushijima, which describes
the HP-IL protocol in detail. I have it at home (but won't
sell it). There is also a description of the IL chip somewhere, with state diagrams, which could be helpful, but
unfortunately my Alzheimer prevents me from remembering where I found it. Try to ask the web search engines.

[Christoph Klug]

Two HP specification papers exist :

The HP-Il Interface Specification HP 82166-90017 (November 1982, nearly 200 pages)

The HP-IL Integrated Circuit HP 82166-90016 (November 1982, Nearly 100 pages)

Furthermore belonging HP 82166 IL-Converter documentations give some more knowledge.

For interfacing external hardware to HP-41 and HP-IL I created the nice I/O-Board and new IL2000 interface systems.