HP 98046b serial interface

[Tom Ward]

Hello all,

I recently acquired a HP 9825t and have a project in mind that will need a serial interface. I've not had much luck tracking down 98036a serial interface, but may be able to get my hands on a 98046b. Will this combination work?

Thanks,
Tom

[Paul Berger (Canada)]

(03-09-2017 12:30 AM)Tom Ward Wrote:  Hello all,

I recently acquired a HP 9825t and have a project in mind that will need a serial interface. I've not had much luck tracking down 98036a serial interface, but may be able to get my hands on a 98046b. Will this combination work?

Thanks,
Tom

The install guide for the 98046B (found on hpmuseum.net) suggests it is only for the 9835/45 and the "Tech Data" sheet for the 9825B/T, the last model of 9825 does not list it as an option. The 98046 is a quite different serial interface with an embedded micro-controller to handle some of the protocol primary so that it can support synchronous serial protocols as well as async. It will physically fit but it is unlikely that the 9825 has software support for it.

A quick search on the internet turned up a couple places that claim they have one, I am surprised they are so scarce, I would have thought they would be a common interface card used in 9825/31/35/45.

Paul.

[Tom Ward]

Hi Paul,

I had read the install and service manual for the 98046, and saw that as of that publication it did not appear to be part of the schema but didn't know if the 9825t was introduced before or after the hpmuseum.net manual. Basically grasping at straws. Patience is a virtue, so I'll wait and search until 98036a presents itself.

Tom

[sleibson]

Hi Tom,

I designed the 98036A and wrote the Systems Programming ROM that went with it (but is not required). The 98036A is the only serial card that works with the 9825 (any version). The 98046B was designed specifically for the 9845 to handle more complex synchronous serial protocols and it needs a language ROM in the 9845 to work while the 98036A was designed to operate like a simple parallel I/O card (i.e you can print to it). The Systems Programming ROM extends the abilities of the 98036A and adds a few other interesting capabilities like "store A$".

A company called Filtronetics has listed a 98036A for many years as a used sale item and may still have one to sell you:

http://www.filtro.net/about-us/equipment.htm

I successfully bought an I/O card from them years ago. I bought back a lot of the things I designed at HP over the years, mostly from eBay.

Good luck!

--Steve

[Tom Ward]

Steve,

I've read your 9825.com site several times through and enjoy each reading! After Paul's post (thanks Paul), I searched a bit deeper last night and found a 98036a at filtro.net (the one your post points at),it should be on its way Monday. As a positive side note, I found the i/o expander (that's your design as well as I recall) for a reasonable price on a different site and it should be on its way Monday as well. Good or bad, eBay has been where most of the more interesting HP gear I've acquired came from (usually scrappers).
Btw, thank you for your website and the info on the 98036a.

Tom

[sleibson]

Happy to help, Tom. I'm glad that Filtronet interface card finally has an appreciative home. There used to be a cavernous building here in San Jose just filled with old HP gear called Crisis Computer. It looked like that scene in Indiana Jones where the government stored the Ark of the Covenant. They kept old DoD weapons programs running long after the people who developed those systems went away. I think some 9825 systems were performing automated tests on Tomahawk missiles, for example. I think Crisis is long gone but they do sell off parts on eBay still from time to time. I bought a Systems Programming ROM there. Bought it on eBay and picked it up in person.

Yes, I did design the 9878 I/O expander. It was my first project for HP, in 1975 right after I graduated. I had a blast designing that box. In theory, it doesn't work. In practice, it does. I was the only EE on the project and Jerry Nichols was the only mechanical engineer. You don't find many projects at HP with one EE and one ME these days. Things are way too complex.

Also, glad you like the 9825.com site. It was a work of love.

--Steve

[Paul Berger (Canada)]

Steve,

I quite enjoyed reading your site as well, I am a happy owner of a 9825T and 9835A and now all the interfaces except the BCD card. I have never really looked for a BCD card because I have any use for one, but it would appear they are pretty rare. I also have an 9878 I/O expander so I can plug them all in. For mass storage I have both a 9885 and 9895. Late last year I was graciously loaned a 98228A storage ROM which I cloned so that I could support both 9885 and 9895 on my 9825T. If you where so inclined we would welcome you at the VintHPcom group on groups.io where we talk about old HP computers like the 9825.

Paul.

[sleibson]

Wow Paul. Cloning those old ROMs is quite an achievement. I too have a 9895 but no ROM. Doesn't matter much since I no longer power up these machines. The electrolytics are well past their sell-by dates.

Thanks for the invitation to hang out with the other desktop computer users. I'll drop by some time to see what's what. I'm still actively engaged with my Xilinx Xcell Daily FPGA blog, so I don't have a lot of time for HP history (I left HP in 1980), but I do like to discuss it from time to time. Especially if I can be helpful.

--Steve

[sleibson]

Oh, almost forgot. That BCD card was designed by Larry Smith and the reason for its existence was the reason HP9825.com came into being. I spotted an old Non Linear Systems catalog in a used bookstore across the street from my condo. All of the old, old DVMs in that catalog had BCD I/O on the back panels, as did HP's original DVMs. That was the printer interface and was a simple electrical extension of the BCD counters in the DVMs. There was the data already on an I/O terminal and it was a simple matter to build an I/O card to allow a computer to capture and process that data. It's what we had before RS-232C, then HPIB/IEEE-488, and then finally USB and Ethernet. It's just a continuum.

So, within hours of spotting that catalog, I knew I had the seed crystal for the Web site. I called my wife from work and asked her to go and buy that catalog before it got "snapped up." I could not let another hour go by. The HP9825 was designed from the ground up to be an instrument controller and that focus is one reason, one of several, that led to its success. The reason that focus came to be was recently documented in an hour-long presentation by Don Morris at HHC 2016:

https://youtu.be/iQdtk3pk86M


--Steve