About OpenPA
OpenPA is an information resource for PA-RISC computers, technology and operating systems; a registered serial publication with ISSN 1866-2757. First published in 1999, OpenPA has been edited and updated regularly for more than 25 years as an independent, non-commercial publication.
PA-RISC is a RISC computer architecture designed by Hewlett-Packard in the 1980s, used in HP 9000 and Visualize workstations and servers until the 2000s. Some older predecessors of PA-RISC from the 1980s and successors based on HP/Intel Itanium are also covered, as are available Unix operating systems.
OpenPA is based on public information from sources such as HP handbooks as well as articles, journals and conferences. OpenPA does not represent and is not affiliated with Hewlett Packard in any way. This site is provided as a non-commercial informational resource only, for owners and users of PA-RISC computer systems and software.
Paul Weissmann is editor of OpenPA and also publishes OpenKRITIS on critical infrastructures and Insel Westberlin, a Berlin archive. He can be reached by mail.
How come?
OpenPA.net was founded in December 1999 at a time when Google just started and Wikipedia did not exist yet. The idea was a central independent resource for information on PA-RISC Unix computers, which were widely available in the second-hand market of the late 1990s, early 2000s. OpenPA and contributions peaked in those early years with a lively community around PA-RISC and open source systems.
1999-2004
OpenPA, the open PA-RISC information resource was started in 1999 when second-hand PA-RISC systems became affordable for hobbyists after being phased out of the industry for Windows NT and Linux servers. Not much PA-RISC information was readily available then on the Web, when other Unix and RISC platforms such as Sun were documented well.
A 715/100 from a local newspaper ad started the interest and slowly led to an archive of PA-RISC documentation from the 1990s. Edited into a simple web site with frames, it was published with hosting provided by Bill Bradford of SunHELP. The late Mickey appeared soon after, with lots of PA-RISC wisdom and first forays into the new PA-RISC open source scene – still incomplete then.
After two years this site moved into its own space on a Digital DECstation 5000 on 1Mb dialup.
Increasing support from HP for the PA-RISC Linux project made much PA-RISC documentation available and open source operating systems made progress, including OpenBSD and Linux.
Most HP 9000 700 and many lettered
workstations have been documented on OpenPA since that time, as were most PA-RISC processors, chipsets and operating systems.
2005-2008
Updates became less frequent after 2005 with only minor additions such as then-new 64-bit PA-8800 and PA-8900 processors, some bits on PA-RISC architecture and more operating systems. An OpenPA print edition was finally released with several hundred pages.
A burst of activity in 2008 resulted in much new content like the last 64-bit PA-RISC workstations and rp server series, mainframes such as Convex SPP, V-Class and several early HP Itanium were added as well. Information on the fringes of PA-RISC was investigated, including third-party processors and OEM systems from Japan and early-1980s PA-RISC computers.
2009-2019
Update frequency and additions stalled considerably after 2008 with mostly low-intensity maintenance and reshuffling of content for more than a decade. The Internet, public source and PA-RISC information changed a lot during that time.
Most HP PA-RISC documentation disappeared during the 2010s, many original links and references had to be removed. Interest in and support for PA-RISC in open-source systems dwindled as well.
Major housecleaning was done on OpenPA several times after 2016, checking links and content and rewriting much original language. Some new additions included a PA-RISC timeline and original equipment prices, a new OpenPA print edition and some restructured sections plus various cleanups in the backend.
2020-2025
OpenPA updates and PA-RISC activities started again in the 2020s with some longer articles written after the 20-year anniversary. Many efforts have been made to find new sources to properly document PA-RISC history, based on archive.org and other archives.
Some new PA-RISC paths were pursued and OpeNPA content has been made more readable, sources were consolidated and some rather unknown aspects of PA-RISC documented, like PRO, the 1980s, HP-UX and some odd operating systems, Apollo and PRISM.
Many OpenPA articles were revised and rewritten, bad ideas from previous decades reversed and some severely outdated text updated with new language. There is still some old content throughout OpenPA and many ideas still to be implemented. More information on the fringes was added – Intel-based Visualize computers and RISC laptops of the 1990s.
The yearbook
| Year | Changes | Content | Backend |
|---|---|---|---|
| 1999 | Started | PA-RISC overview from the 90s | Frames, dark-mode |
| 2000 | 7 | HP 9000 700s, operating systems | Hosted at sunhelp |
| 2001 | 7 | 32-bit processors, hardware, more systems | mickey@ appeared |
| 2002 | 21 | BSD, A/B/C/J lettered-systems, some 64-bit, X-Terms | Renamed, own server |
| 2003 | 30 | Complete 64-bit, four-digit systems, 3rd-party, more OS | |
| 2004 | 14 | Benchmarks, FOCUS, graphics, SCSI, architecture | Complete revamp, CSS |
| 2005 | 3 | Small updates | |
| 2006 | 4 | Final PA-RISCs - Mako, C8000 | OpenPA book |
| 2007 | 3 | History, small updates | Limited paperback |
| 2008 | 18 | Mainframe/Cell, Itanium, 1980s PA-RISC, others | |
| 2009 | 3 | CPU and I/O architecture, much cleanup | 10y anniversary |
| 2010 | 2 | T-Class, chipsets | |
| 2011 | |||
| 2012 | 1 | OpenPA book update | |
| 2013 | |||
| 2014 | 1 | Cleanup and housekeeping | |
| 2015 | 2 | Handle disappearing sources and documents | |
| 2016 | 6 | Restructure chipset content, timeline, cleanup | |
| 2017 | |||
| 2018 | 3 | PA-RISC story, OS updates, disappearing sources | Cloud move |
| 2019 | 20y anniversary | ||
| 2020 | 3 | Agilent PA-RISC, many systems updates | |
| 2021 | 2 | Content mopup, OS history | Backend mopup |
| 2022 | 3 | Research OS reorganization, Apollo/PRISM, mopup | OpenPA book update |
| 2023 | 5 | PA-RISC history, 1980s, PRO in Japan, OpenPA and Internet | |
| 2024 | 19 | Oddball OSs, HP-UX, Visualize FX, PA-RISC architecture, Intel Visualize, RISC laptops, graphics |
Frontend, graphics |
| 2025 | 11 | HP-UX Unix software, archives, much text and structure | OpenPA book update |
People
Paul Weissmann is the editor of OpenPA. This site © 1999-2025 Paul Weissmann, Berlin, Bonn, Palo Alto, San Francisco, unless otherwise noted. No parts of this site may be reproduced or copied without prior written permission. Commercial use of the content is prohibited. The OpenPA editor can be reached by email.
Many people helped OpenPA with contributions and support over the years:
- Bill Bradford † for hosting this site in its early days
- Dave Fotland for the PA-7200 and HP 9000 840 information
- Dennis Grevenstein for information and documentation
- Frank McConnell for the HP 9000 500 and FOCUS information
- Götz Hoffart for the CSS/HTML help, inspiration and fixes
- Grant Grundler for support with HPPA and PA-RISC Linux over the years
- Helge Deller for additions to PA-RISC Linux and QEMU
- HP Computer Museum for preserving much old documentation
- Internet Archive for hosting much long-lost documentation
- Michael Piotrowski for corrections and HP-UX background information
- Michael Shalayeff † for providing PA-RISC and general wisdom
- Mike Hibler for input on HPBSD and Mach operating systems
- Miod Vallat for various PA-RISC explanations and corrections
- Ruby Lee for the PA-RISC Stirling information
- Thibaut Varene for PA-RISC Linux help and the development section
- Tiziano Garuti for the great 1000bit.it resource on old documentation
- Thomas Schanz for his wonderful PA-RISC photos
- Ti Kan for the technical explanations on the Stratus architecture
- Dozens contributors and readers that sent in corrections, clarifications and questions over the last decades
Thank you all!