Archive for the 'Museum News' Category

March 28th, 2014 ~ by admin

Motorola 68020 Processor die shots and description

1985 production 68020 'XC' denotes a not fully qualified device.

1985 production 68020 ‘XC’ denotes a not fully qualified device.

In 1979 Motorola wow’d the world with the introduction of the MC68000 MACSS (Motorola Advanced Computer System on Silicon).  One of the first single chip 32-bit processors.  In 1982 the design was upgraded and revised, and released as the 68010.  Performance wasn’t that much better then the original 68k so it saw much smaller adoption.

In 1984 Motorola continued the 68k line with the 68020.  Speed was greatly improved, up to 33MHz.  It was originally made on a 2 micron HCMOS process, allowing the design to use 200,000 transistors and integrate additional addressing modes, co-processor support, and multi-processor support.

The Swedish Computer archeology blog Ehliar has a nice article and die shots on its architecture and design.  Check it out.

November 23rd, 2012 ~ by admin

The WITCH Rises – Dekatron Computing

Harwell Dekatron

Recently another antique computer was restored to working condition.  Originally called the Harwell Dekatron, the WITCH (Wolverhampton Instrument for Teaching Computing from Harwell) was built in 1949-1951.  Back in the early days of computing, it often took years to build a computer, rather then the minutes it takes to make a iPhone in today’s factories.

The WITCH was a decimal computer, storing data not in 0’s and 1’s of the transistor age, but actual decimal digits.  It originally could store 20 8 digit numbers (0-99,999,999 or 23 binary bits) but later was upgraded to support up to 40, which was considered more then enough (such short sighted statements did not end in the 50’s, if you’ll remember Bill Gates comment about 640k of RAM is all anyone would need.)  Data on the WITCH was stored on Dekatron tubes, a Cold-cathode device filled with Neon (or Argon) that could represent 10 digits.  Sending a pulse to the Dekatron would cause the glowing Neon dot (and its associated high voltage) to move from cathode to cathode, thus allowing data to be stored.  One side effect of having decimal data, and glowing orange dots for volatile storage is you can literally SEE what is in memory.

Dekatron in operation (courtesy of

The WITCH was mainly used to perform mathematical computations.  It was not a fast computer, it took it a good 10-15 seconds to perform a multiplication.  Many humans with adding machines could actually work the problems faster, however the WITCH never complained of carpal tunnel nor did it need breaks.  The Harwell Dekatron was slow, but is was steady and quite reliable.  It could go for days (providing it had enough problems fed to it on paper tape) without error or breakdown and that is what made it so useful and worth restoring.

Check out the BBC article and video of its operation and listen to the relays click, and see the glowing Neon of computational history.

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Museum News

October 26th, 2012 ~ by admin

Paul Allen’s Living Computer Museum Opens To Public In Seattle

Paul Allen, co-founder of Microsoft, has just opened the Living Computer Museum in Seattle.  Living, of course, due to the fact that many of the vintage computers on display are working units.  Some very rare systems including the only working PDP-7 in the entire world (UNIX was created to run on the PDP-7, so its a rather famous machine) and other DEC’s are on display.  There are original IBMs, TRS-80s, Novas, and yes even some Apples.  No Apple 1 as of yet.  Perhaps Paul could pick up this latest one on auction? Should go cheap as it seems to be lacking an original MOS 6502 CPU.

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Museum News

August 29th, 2012 ~ by admin

The History of the Floppy Disk

Shugart SA400 Floppy Drive

The HP Input Output Blog has a nice write up on the floppy disk/drive.  A very interesting read about a device many took for granted, and many of today’s generation did not ever get to experience.  Many do not realize its humble beginnings, and the importance that Steve Jobs, ‘the bum in the lobby,’ played in the 5.25″ floppy becoming a standard.  The 5.25″, holding twice what a 8″ floppy could, was developed by Shugart Associated in 1976.  Shugart went on to become Seagate, known today for their hard drives.  Hard drives that can store over 2 Terabytes of information.  The original 5.25″ floppy? 160K, per side.  An 8 inch? 80K a side.  Interestingly enough, it was sometime before the Floppy Drive Controller (FDC) was integrated onto a single chip.  Many original Shugarts used an Intel 8080 CPU for drive processing.  The Commodore 64’s famous 1541 Floppy Drive ran its own 6502 type CPU, and was designed in such away you could actually load code directly to the floppy drive 6502.  In the 1990’s attempts were made to increase the capacity, speed, and versatility of the floppy.  Apple created a 2.88MB 3.5 inch floppy that never really caught on.  There was the LS-120 drive which could use normal 1.44MB disks as well as special 120MB disks (was handy, but so few people had them, they had limited use).  Ultimately, like most all technology the floppy has passed by the way side, today’s floppy is the USB Flash drive, holding many gigs of data for only a few dollars.  And like the floppy, flash drives are used commonly for sneakernetting files around the office.  Perhaps the mbile version of the floppy is the Micro-SD card, remember when Sony built a camera with a 1.44MB floppy drive built in?  Not een large enough to store the picture from a cell phone camera today.


Head on over and check out the article, its a fascinating story….

August 16th, 2012 ~ by admin

Hans Camenzind: 25 transistors, 2 diodes and 15 resistors that changed the times

Yesterday Hans Camenzind passed away at the age of 78.  Hans was a notable inventor of Swiss decent.  Perhaps the most famous of all his inventions occurred in 1972 while working on a contract with Signetics he invented the 555 Timer chip, a simple oscillating IC that was inexpensive, and easy to build with.  Now, even 40 years after its introduction, around a billion per year are still made, by dozens of companies around the world.  The 555 Timer is often one of the very first IC’s electronics hobbyist begin experimenting with.  Its applications are far reaching and while certainly not a CPU, its significance, and that of Camenzind, should not be forgotten.

The 555 Timer has of course been used in many many computers, notably in the Apple II computer as a joystick controller (558 Timer, which is a quad 555).  Other uses include the IBM PC, Ataris, and many many more. In honor of Hans Camenzind, and the 555 Timer, go experiment with one and experience the joys of a device over 40 years old. Dont have one? They cost a whopping $0.95 at Sparkfun.

August 14th, 2012 ~ by admin

Spacecraft Processors: Mars Curiosity

The Spacecraft CPU page has been updated, after a long gap.  It now includes information of the recently landed Curiosity Lander, some new information on the 45 year old Voyager series as well as some on New Horizons, DAWN, and several others, so check it out.

BAE RAD750 Single Board Computers

The Curiosity (and Mars Reconnaissance Orbiter,) Run a BAE RAD750 @ 200MHz

September 29th, 2011 ~ by admin

Museum update: Several thousand added

Leaving on a trip so I dumped all the pending CPUs/EPROMs etc to a gallery.
There are litterally thousands of new CPU’s, EPROM’s, FPU’s, and some oddities.

They are sorted by manufacturer (technically brand)

You can view them in gallery form here:

You may also view them in raw directory form here:
and a few that didnt make it into the gallery here:

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Museum News

August 2nd, 2011 ~ by admin

30 Years ago today: The IBM 5150 PC

Intel D8088 - 1981 Production

Hard to imagine its been 30 years since IBM released the 5150 Personal Computer for the grand sum of $1265 thus starting the flood of PCs.  Build with generic hardware, and MS-DOS from Bill Gates and crew (itself only released a month prior), the 5150 did away with proprietary, the MS-DOS OS was not exclusive to IBM, and the hardware was essentially off the shelf, using Intel’s 4.77MHz 8088 (cut down version of the 8086) processor and a discrete 256k of RAM.  Other companies, could, and did, in mass, replicate and add to the 5150 making the 8088, and with it the x86 instruction set the de facto standard even to today. (though ARM has been making a large impact as of late due to the rise of mobile computing)

Here is an early add for the 5150, not only have we come a long ways in computers, but advertising as well.

April 25th, 2011 ~ by admin

50 Years ago today: The IC was Patented

On April 25th, 1961 Robert Noyce, then working at Farichild Semiconductor, received Patent 2,981,877 SEMICONDUCTOR DEVICE-AND-LEAD STRUCTURE.  This was the patent for how to make integrated circuits, containing multiple silicon based transistors, on a single die.  Six months prior Jack Kilby received a similar patent, but for geranium based devices.  Silicon became, for a variety of reasons, the preferred material and 50 years later we now use some of the same principles to build IC’s with over a billion transistors on them. The diagram in the patent showed a device with 8 components on a single doe, 1 transistor, 2 diodes, 2 capacitors, and 3 resistors.

In 1968 Noyce, and Gordon Moore (of Moore’s Law fame) left Fairchild and founded Intel. Fairchild Semiconductor was the ‘incubator’ of many such semiconductor companies, Intersil, Teledyne, Xicor and AMD were all founded by former Fairchild employees

April 21st, 2011 ~ by admin

Inside the 1802: a View

RCA 1802E Die - 20x magnification -

The talent at continues.  After imaging and building a complete simulator for the MOS 6502 they did the same for the Motorola 6800 (from which the 6502 was based).

We have sent several chips and they have now imaged the RCA 1802 that we sent.  What is very interesting is how little marking are on the die, the only that I could see was the number ‘10824.’  This particular chip was dated early 1981 though the 1802 COSMAC was designed in 1976 and was one of the first CMOS microprocessors.  The 1802 had around 5000 transistors (Visual6502 will let us know exactly how many once they are done, and of course what each and every one of them does). For higher res shots and more info see here