PDP-11 update

greenspun.com : LUSENET : TimeBomb 2000 (Y2000) : One Thread

A brief techno update. I asked Rick Cowles about the PDP-11 system(via his forum) in the electrical industry. Apparently, they are fairly common, especially in plants built in the 70's and 80's. This is a very common system used for many different applications. About 600,000 of them are (or have been) used worldwide. I wouldn't be surprised if 400K are still running (cheap, reliable, fast). Anyway, its operating system, RSX, is non-compliant. A single company, Mentec, still supports RSX and does offer operating system updates. I wonder if a single small company can support 400K users? Anyway, their methodology is clumsy at best. Below is how they represent post y2k dates.

See http://www.mentec.com/Y2K/Y2K_MAP.htm

The two bytes will be encoded as follows: Low byte-Low order decimal digit of year, in ASCII. High byte-Quotient of years since 1900 divided by 10, plus 608. This represents the ASCII high digit of the year from 1900 - 1999. In 2000, however, this will result in ":" being stored for the high digit of the year. For years 2010 through 2019, ";" will be stored, and so forth. This change should result in another 200 years or more of file representations Table 1-1 Storage of Dates in RSX Systems after 1990

Calendar Year Year Field Representation 1900-1999 00 - 99 2000-2009 :0 - :9 2010-2019 ;0 - ;9 2020-2029 <0 - <9 2030-2039 =0 - =9 2040-2049 >0 - >9 2050-2059 ?0 - ?9

Sounds great Huh? Except, how many application packages can understand this date representation? Answer - none, unless you wrote it that way very recently. The PDP-11 often uses archaic application packages sold by vendors that are now so much cyber history dust. In many of its real-time applications, I consider the PDP-11 part of the embedded system of systems. As a company, unless you are willing to stand in a long, long line awaiting operating system updates from Mentec AND you are willing to rewrite your application code, your PDP-11, and whatever application it is controlling, is toast. Why should you non-codeheads care? This is a firm example in the embedded/real-time control area that you can point at and say THIS WILL FAIL. You should be asking your neighborhood refinery, power plant, pipeline control station, water purification plant, etc. do you have a PDP-11?

-- RD. ->H (drherr@erols.com), November 28, 1998


Two weeks ago, I posted that the Del Marva Peninsula Power plant runs a PDP-11.

Kiss it good-bye.

-- Paul Milne (fedinfo@halifax.com), November 28, 1998.

As a foot note, I work for the Postal Svc as an Electronics Technician and their older systems use PDP11-23's, 11-4?(45's I think) and 11-83's. Unless they updated and removed a lot of this stuff since I transfered out of Denver in 93, You might not get your welfare/VA/SSI check in early 00 if the doom and gloomers are right.

-- nine (nine_fingers@hotmail.com), November 29, 1998.

This is PRECISELY the problem with the Mid-East well-head/pipeline/dock-side ship transfer systems I talked about in September. These systems were installed in the 1970's through the mid 1980's by Japanese companies that did their ASCII functin documentation in Japanese!! They can maintain service contracts and control by writing manuals in Japanese. How is your Japanese? I've been living here since 1992 and I would never be able to tackle a project like this in any reasonable length of time.

All Japanese software is tweeked to make it "special." Even Japanese DOS (DOS-V) is tweeked to make problems for non-DOS-V applications. It's the Japanese style of doing EVERYTHING.

The Japanese companies who designed and installed these systems (at least the one's still around and with a few people left who remember and deal with these systems) will never be able to fix these systems in time. The local Mid-East operators have neither the skill nor the desire to open these cans of worms. They rely on the vendors to maintain all systems. The Japanese do not have enough people to "re-do" these systems. They can't even handle their own domestic systems.

-- PNG (png@gol.com), November 29, 1998.

Maybe it's time to e-mail this thread to a techno-type at my local PG& E offices. Thanks.

-- Diane J. Squire (sacredspaces@yahoo.com), November 29, 1998.

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