AMW Visit 2007

On Friday the 20^th of April after the 2007 Asilomar Microcomputer Workshop (AMW) closing barbecue luncheon, Jean and I were scheduled to head back home on that evening's JetBlue red-eye from San Jose to New York City's Kennedy airport connecting to a Rochester NY flight Saturday morning. The air connection on JetBlue went quite smoothly with respect to weather conditions cross country and with respect to the operations of this fledgling airline. JetBlue is definitely an airline which we will use again without hesitation should its scheduled flights fit our future plans.

However, our plane was not scheduled to leave until late in the evening PDT for arrival in NYC at about 7AM EDT. So what could we do with an extra few hours in the Bay Area after the drive to the San Jose area?

The Asilomar Microprocessor Workshop always ends after its final luncheon early Friday afternoon so that attendees can start their journeys home to their normal physical domiciles all over this WWW connected planet. Thus after lunch and good-byes to all our AMW friends, Jean and I drove from Asilomar on the south side of the Monterey Peninsula north to the Computer History Museum in Mountain View. After a half an hour or more of San Jose area early rush hour traffic at the end of our two-hour drive, we arrived at the museum.

Ever since 2001 when I donated a set of my BYTE Magazine bound volumes for 1975-1978 [ BYTE Bound Volumes 2001 ] to the Computer Museum History Center, I have been intending to arrange to stop by before or after an April AMW. Jean and I first thought about stopping at the Computer History Museum on our first joint trip to the Asilomar Microcomputer Workshop in April 2004 after we married in 2003. Time and events kept us from visiting the museum in 2004.

We did not attend 2005's AMW and instead that April went to Jean's often coincident Society for Neuro Immune Pharmacology [SNIP] scientific meeting that year in Florida. In 2006, the two meetings did not overlap, but for one reason or another we did not stop by the Computer History Museum that year after the AMW.

In 2007, we went to Jean's SNIP meeting in Salt Lake City UT the week prior to the AMW. Then, we spent a few days in Monterey before attending the AMW. It turns out that 2007 was the year Jean and I were first able to visit the Computer History Museum, thanks to the hospitality of fellow AMW attendee Mike Cheponis. In talking with Mike over dinner or at breaks between sessions, he definitely wanted to see if he could arrange to show us the restored computers he works on in his spare time as well as the rest of the Computer History Museum. So, we arranged to meet him circa 17:00 Friday April 20 at the museum for an impromptu tour prior to our late evening departure from the nearby San Jose airport. Mike is involved in the restoration of several antique computers in the museum's collection and wanted to show off his success restoring one of the first Digital Equipment Corporation computers, an early (1960) PDP-1.

A Brief History of The Computer History Museum

[Isn't Recursion Fun? :-)> ]

The Computer History Museum is dedicated to preserving and presenting the stories and artifacts of the information age, and exploring the computing revolution and its impact on our lives. The museum was originally established circa 1979 by the Digital Equipment Corporation's Gordon Bell and his wife Gwen at a Digital Equipment Corporation facility in Massachusetts. The museum's first name was, naturally, the Digital Computer Museum.

By 1983, the ever expanding museum's collection outgrew the DEC space available and moved to the city of Boston where it was renamed the Boston Computer Museum. I have known about the Computer History Museum's predecessor, the Boston Computer Museum since shortly after its founding in the Boston MA area. For several months in the 1980's or early 1990's I loaned my collection of 1975-1980 BYTE Magazine original Robert Tinney cover paintings to the Boston Computer Museum for the duration of a set of special personal-computer oriented exhibits that they produced. While I still lived in Peterborough in southwest New Hampshire I never actually got a chance to visit the Boston Computer Museum after the time of my loan of my framed BYTE cover paintings for that exhibit.

Several years later, the Computer History Museum in Mountain View California was established in 1996 as the Computer Museum History Center when the Boston Computer Museum sent its collection of large mainframes and historical artifacts to quarters at Moffett Field, California so that the original Boston Computer Museum could concentrate on computing-related exhibits for children in association with the Boston Children's Museum.

Then in 1999, the original Boston Computer Museum ceased separate existence and merged with the long established Boston Museum of Science. Also in 1999, The Computer Museum History Center became an independent entity and began moving forward with its mission to "preserve and present for posterity the artifacts and stories of the Information Age." The remaining original Boston Computer Museum artifact collections traveled to Moffett Field in February 2000, adding significantly to the archives of the Computer Museum History Center.

The Computer Museum History Center (as it was then called) was the topic of a talk seeking artifacts at the 2000 Asilomar Microcomputer Workshop (AMW.) As a result I decided to donate one of my sets of six early BYTE Magazine bound volumes [1975-1978 issues] to the Computer Museum History Center. I announced this decision at my short informal Thursday evening talk at that Y2K AMW. I finally followed through by lugging the set of 6 bound volumes with me to the next AMW in 2001 [see BYTE Bound Volumes 2001 .] Also in 2001, the Computer Museum History Center shortened its name to Computer History Museum.

The information in this box combines my own recollections with information from the Computer History Museum's background information site, http://www.computerhistory.org/about/press_relations/background/ that I found on line referenced by the Wikipedia entry for the Computer History Museum.

The Computer History Museum is now located in a never-previously-used computer industry office / factory building at 1401 North Shoreline in Mountain view California. One of the Computer History Museum's prize artifacts on display is a genuine, restored operational IBM 1401 system (Mike Cheponis also had a hand in its restoration.) I wonder if the Computer History Museum made a special arrangement with the post office for their street address number?

Whatever the origins of the street address number, the museum is located down a ramp from the California Highway-101 freeway. It is just around the corner from where the ramp joins the local road North Shoreline. The museum is perhaps 15 minutes drive north of the San Jose Airport or a half hour drive south of San Francisco airport, all drive times depending on traffic of course :-)>.

I captured image 1 when we first got to the grounds of the museum that afternoon. The clock readout in image 1 is 19:32 EDT according to my Nikon 4600 digital snapshot camera that I take with me on trips for such pictures – off by three hours and a few minutes from the true PDT local time when I captured the image. This time discrepancy applies to all the images in this article :-(> . [Maybe on our next trip, I'll finally remember to reset the camera's clock to local time!]

Mike told us that building in which the Computer History Museum is now housed is permanent – it is owned by the museum as opposed to its quarter century history of temporary quarters in Massachusetts then in California. When the museum moved to California, for a few years it was located next to the nearly century old dirigible airship hangars [sans dirigibles since the early 20^th century] at Moffett Field. That first west coast location at Moffett Field is just a few miles south of its present, ultimate location.

After we arrived, Jean and I explored the grounds by walking the quarter mile or so around the building several times. On one of our first such circuits of the premises, I captured Image 2 of Jean circa 16:35 near the roadside sign on Shoreline:

Mike arrived after fighting the same heavy route 101 traffic that we had encountered earlier. The remaining pictures in this portion of my site are more or less in the same sequence that I captured them after we started touring the Computer History Museum's physical artifact displays with Mike.

I captured Image 3 of a display of a dozen or so examples of humankind's earliest computational device, the abacus calculator. Since millennia BCE [Before Current Era,] these devices have been used by merchants to facilitate calculations in commerce. Perhaps given our current phase change in civilization brought about by the invention of modern electronic computers, the traditional “BCE” acronym of science should be replaced as an acronym by “BECE” for Before Electronic Computer Era... :-)>]

I captured Image 4 when we moved past a display centered on that famous IBM marketing slogan of the mainframe computer era, “THINK.” The display shows a collection of typical desktop versions in several natural languages, marking the international nature of the computer revolution.

Then Mike led us to his latest “baby,” the restored and working PDP-1 computer shown here running a characteristic test image on its ancient round monochrome video display. This test pattern is created by a simple machine language program running in the machine. Since the memory technology of early computers such as the PDP-1, IBM 1401 and IBM 360 model 30 restorations at the museum is core memory, Mike and his restoration colleagues at the Computer History Museum leave typical programs such as this simple graphic test pattern generator and other more complex demos in memory all the time. Then when he or his colleagues turn on these slow, power hungry machines for demos, all they have to do is enter a control panel jump instruction to go to the starting address of the programs they want to run for visitors. This works because core memory, as well as being the first effective computer memory technology, is also a “non-volatile” memory technology that retains programmed patterns in the absence of power.

Continuing on the theme of the Computer History Museum's restored PDP-1, I captured Image 6 to show a portion of the machine's front panel, centered on its very essential paper tape reader. The circa 1960 PDP-1 was too early for modern developments of the last several decades like hard disk and even floppy disks or DEC's later “DECTape” magnetic tape. So the only way to store PDP-1 programs offline was to punch numerical representations of machine language codes into paper tapes on a Teletype machine, toggle in small machine language programs on panel switches or load programs generated by Teletype punched output of primitive software tools.

Above the paper tape reader at the top of Image 6 is a rack for quick access to paper tapes of programs that are in common use with the machine. The binary indicator lights of the PDP-1 control panel are below the paper tape reader here. Out of view under the indicator lights is the characteristic set of binary toggle switches that are used to manually enter short programs, a feature that lasted through the PDP-8 that I used to access a PDP-6 in a year as a grad student in the nuclear structure physics lab at the University of Rochester circa 1970/1971. If I correctly recall such front panel switches still still existed on the PDP-11's of the late 1970's..

Image 6 -- the restored PDP-1's console, paper tape reader and frequently used programs bin, DSCN1897 for WWW.jpg

Oh you do not have enough room to store all your programs in the 7 slots on your PDP-1 computer's front panel? The paper tape era of the PDP-1 had its equivalent of a mass storage paper tape device, an image of which I captured in Image 7. This “mass storage” manual “random access” storage rack holds 48 paper tapes in its slot positions. File access time of this technology is on the order of seconds to tens of seconds. I will leave as an exercise for my readers to calculate the maximum character capacity of the perhaps inch thick stacks of fanfold paper tape held in this device, but it is certainly measured in units far smaller than megabytes :-)>

Image 7 -- the restored PDP-1's auxiliary desktop paper tape program library, DSCN1896 for WWW.jpg

Opening up the door in the back of the PDP-1, Mike showed us its “guts” which I capture here as Image 8. The shiny stripes in this rack are the metal brackets on the edges of the printed circuit (PC) card logic elements that carry out the operations of this archaic transistor-and-discrete-components electronic computer (see also Image 9.)

Mike then grabbed hold of a food storage bag that contained an example of one the ever needed spares for the printed circuit card logic elements of the PDP-1. I captured Image 9 from this random logic [pun intended] card of the PDP-1. On this card I count 8 active logic devices, the row of transistors in shiny metal cans. In addition to the transistors their may be a dozen or so silicon diodes in little glass cylinders with wires on either end – to say nothing of a number of color coded resistors, and different kinds of capacitor components.

Moving on in the Computer History Museum's exhibits, Mike directed us to this interesting display hanging from the rafters. Image 10 captures a dozen or more no longer operational core memory frames hanging from the ceiling to show their varieties of organizations and sizes. The frames have a ferrite single bit memory magnetic “core” at each intersection of the orthogonal X and Y wires strung on the frame. Wires threading diagonally through all the cores together with the X-Y grids are used to individually access each core as an addressable bit. In a very superficial description, the “1” or “0” state of a core's magnetization is read or written by the coincidence of specifically engineered pulses on the X, Y and diagonal sense wires of the array as set up by a large amount of support electronics that drives and senses the pulses. A fuller explanation of how this works is found at http://en.wikipedia.org/wiki/Magnetic_core_memory.

In our 21^st century computer world, core memory if used at all on other than “legacy” [AKA obsolete but still used] mainframes is only engineered into new systems which need to be extremely resistant to hard particle radiation fields without extreme amounts of shielding – such as satellite and aerospace applications.

The items on the table under the frames include ancillary core memory system components required to drive the memory arrays when these core memory frames actually were used in computers many years ago.

Image 10 -- a hanging display of core memory frames in CHM, DSCN1902 for WWW.jpg

Mike next led us past what I consider to be one of the most significant displays in the museum. This is a display of the circa 1972 design of the Xerox Palo Alto Research Center “Alto” computer, shown in Image 11. Why is this significant? This is the machine that the innovative computer systems and software researchers at the Xerox PARC [Alan Kay, Adele Goldberg, Dan Ingalls et al] used to invent the modern graphic user interface (GUI) now found in every personal computer.

Their research software system called SmallTalk used this drop down menu-and mouse Graphic User Interface. SmallTalk running on the Alto first demonstrated this then novel interaction method in the early 1970's.

The Xerox Corporation never commercialized SmallTalk or its GUI innovations. By the publication of SmallTalk details in various academic computer science publications, it became “prior art” that prevents anyone else from ever patenting the idea. Thus there never has been and never will be a patent fight over the drop down window GUI of SmallTalk which has since been borrowed by the immensely successful 1984 Apple MacIntosh product which a couple of years later in turn inspired the GUI used in the Microsoft Windows series of softare products. The other side of the picture is that we users of modern PC's get to use an inexpensive, widely available and practical GUI as a result of the Xerox PARC innovations.

In the 21^st century, after Xerox finally dropped the SmallTalk research project and turned the software over to the open source world, the original team of researcher/innovators moved on with their lives at various other companies. SmallTalk still lives in the form of the open source “Squeak” version that can be obtained in platform independent form [various linices, Apple Mac OS's, various Microsoft Windows versions, and as plug-ins for WWW browsers in all modern computers.] See www.squeak.org for the latest information on what's available for download.

For several years now, I have been keeping track of Squeak progress and and derivative developments like the Croquet multiple computer virtual environment software by attending the annual Squeak “Learning Lab” week, in late August at the Apple Hill Center for Chamber Music in New Hampshire at the end of their summer music programs. The main participants at this workshop are associated with MIT and Georgia Tech as well as various original small talk “free spirits” like Alan Kay. The most exciting future possibility [talked about at the 2006 Squeak “Learning Lab” at Apple Hill] is that the open source Squeak applications running on a Linux OS base may become an application software choice for the MIT “one laptop per child” computer when and if it is finally manufactured and delivered world wide – at whatever its final user price.

From the earliest mechanical computers to the present 21^stcentury electronic WWW era, the Computer History Museum covers them all. I captured Image 12 when Mike took us past a display of Google's first circa 1999 production WWW search engine hardware, long since retired. Google now has server farms with hundreds of successors to this machine, performing all manner of on line searches for people around the world. Google and its WWW search paradigm sprang on the internet world from the brains of its two founders Larry Page and Sergey Brin, carried out initially with hardware such as this running their innovative software. The search engine application drives much of the worldwide application and commerce on the internet these days.

Image 12 -- the first Google production server, circa 1999, DSCN1907 for WWW.jpg

The Computer History Museum also has displays of oddities from the early days of computing as well as the more recent items from the personal computer era. Image 13 shows an image I captured while passing a display of the Freon cooled back side of one of the world's first scientific supercomputers, the circa 1964 CDC6600. This plumbing, akin to that of an air conditioner in a home or car, uses the evaporation of liquid Freon to cool electronic components, then collects the Freon gas that results to complete the air conditioning cooling cycle of refrigerant compression, distribution as a liquid and re-evaporation for further cooling. While such active cooling may still be in use in some current large computers or data bank products, it is a specialized niche in the large computer world at best.

Now what Computer History Museum would be complete without some attention to punch card technology? While I did not capture any images in April 2007, the Computer History Museum had a number of displays of punch card equipment starting with the original late 19^th century Hollerith machines first used by the US Census. Hollerith's invention then became the technological basis of the company which became IBM in the 20^th century.

Mike even took us past restored IBM model 029 and 026 keypunches like I used in high school to code my first Fortran II programs during my 1965/1966 senior year on an IBM 1401 (with attendant keypunches) at Sandoz Pharmaceuticals [now called Novartis] located a mile west of my high school on NJ Route 10 in East Hanover NJ. While I did not capture any image of the restored keypunch itself or the restored IBM 1401, I used the restored 026 to to make a souvenir card which I brought home with me. I scanned this card for Image 14:

Image 14 – Scan of the sample IBM punch card I typed on a restored 026 keypunch at the CHM

As a purveyor of historical technologies for the present pre-WWW generation, the Computer History Museum naturally has a printed souvenir / fundraising flier summarizing information found at www.computerhistory.org and http://www.computerhistory.org/about/press_relations/background/ . While this 2006 flier is slightly dated now in 2007, it tells the Computer History Museum story in summary hard copy form. Image 15a is a scan I made from one side of the flier. I made Image 15b by scanning the other side.

File = Carl & Jean visit CHM April 20, 2007 - 2007 05 07 corrected final-final version.odt

Path = C:\CTH\!2007 original folders for WWW\!2007 Computer History Museum\Carl & Jean visit CHM April 20, 2007 - Images from the Computer History Museum\