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EDSAC Computer To Be Rebuilt
nk497 writes with this bit from PCPro: "The first working stored-program computer is set to be rebuilt at Bletchley Park, home to the UK's National Museum of Computing. The Electronic Delay Storage Automatic Calculator ran its first programme in 1949, and was two metres high. Its 3,000 vacuum tubes took up four metres of floor space, and it could perform 650 instructions per second. All data input was via paper tape. The EDSAC used mercury-filled tubes for memory, but in the interests of safety, the replica will use an alternative non-toxic substance. Rebuilding it will take four years, and the public can visit to watch the work as it happens."
The war will have been lost to Jerry by then!
In fact Alan Turing himself pointed out that a mixture of alcohol and water would do the job as well as mercury (he wanted to use gin.) Perhaps "Mercury delay line" just sounded more techie to the Civil Service.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
The first stored program computer was the Manchester Baby
http://en.wikipedia.org/wiki/Manchester_Small-Scale_Experimental_Machine
I was at Bletchley Park a couple of months ago and by chance the National Museum of Computing was open that day. They've got some interesting displays of old computers, and their goal is to get them all running again. They cover everything between EDSAC and modern computers. Their oldest computer is a Harwell WITCH from 1951 (a decimal computer), this is being restored at the moment. Other fun stuff includes a collection of calculators, and a BBC micro with a working BBC Domesday Project laserdisc installation.
It's a separate museum on the Bletchley Park grounds, and its opening times are a bit limited (esp. in winter), so check before you go.
I love the fact that there is a common desire to preserve our historic technological achievements.
Working reproductions of dying / dead machines are a great learning tool -- We are all truly standing on the shoulders of giants today.
I feel that efforts such as rebuilding the EDSAC are in the same vein as those that would create emulators for our out of production computers and video game systems as a cheap way to preserve the past.
What good is the EDSAC or an Emulator without a sampling of the programs the systems used to run? Surely different people would attribute different degrees of importance to different programs -- Thankfully digital storage is abundant and cheap enough that we are capable of preserving entire catalogs of programs.
Notice however, that the more relevant, beneficial and useful a replica or emulator is, the more illegal it is to produce due to patents and copyrights.
I fear that if the current copyright laws could be enforced absolutely, we stand to loose important parts of our history and culture for no other reason but greed. Given the long terms of copyright, it's a safe assumption that much of our digital heritage could decay and be lost before it's legal to reproduce it -- Even under good conditions CDs, Magnetic and Solid State Drives will all fail before 70 years after the author's life has elapsed.
I'm very wary of DRM and the DMCA -- Today we can recreate past works to better understand the significance of the shoulders on which we stand; Tomorrow we may find ourselves searching for footing that has long since crumbled away.
None of the early Zuse machines were stored program computers - they had a relay memory for data and got their instructions from punched tape. The table in the Wikipedia page about the Z3 seems about right:
http://en.wikipedia.org/wiki/Z3_(computer)
The Manchester Baby was the first stored program machine, quickly followed by the modified ENIAC (the original used patch panels and cables) and then the EDSAC. Since the Baby was created to explore ideas for the EDSAC rather than as a usable machine on its own, I guess if you squint enough the article is right in an Obi-wan kind of way :-)
The method of storage in the Baby - a static charge used to represent 1 or 0 - proved to be the most effective form of storage for RAM (as static and dynamic CMOS) and is becoming more and more of a competitor for hard drives. Though CRT memory was short lived, in the long run Williams proved to be right. The Baby was prescient.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
"The Electronic Delay Storage Automatic Calculator ran its first programme in 1949, and was two metres high"
Which also happens to be the height of a killer robot. Coincidence? I don't think so.
they have an app for that.
Barely.
With 650 IPS and 512 18 bit words of memory I doubt much of any kind of monitor, much less OS could be implemented. Still, if anyone would like to give it a shot, there is an emulator available at
http://www.dcs.warwick.ac.uk/~edsac/
Sometimes the light at the end of the tunnel is the headlight of an oncoming train.
Maybe. In theory you might get a scaled down bare bones Linux to run, but even so you would be hard pressed to run any programs with it. Vaccuum tubes were replaced by transistors in the '50s and '60s, which in turn were largely replaced by ICs in the '60s and '70s. A single vaccuum tube preforms the same functionn as a single transistor. The Z80 CPU chip, which came out in 1976, had 8,000 transistors, more than twice the tubes of this entire computer.
The Z80 processes around 40k instructions per second, compared to EDSAC's 650 IPS. That's sixty times as fast as the EDSAC. Imagine how long it would take just to boot!
As I noted in Growing Up with Computers, UNIVAC, a more powerful computer with 5200 vaccuum tubes that first shipped the year I was born, was less powerful than a Hallmark Greeting card.
Free Martian Whores!
We'd have the mind-numbing processing power to get my garage door open, and one less US state.
I swear to God...I swear to God! That is NOT how you treat your human!
... since LEO, the first commercial business computer, was based on the EDSAC design. Amazingly LEO computers were still in use in 1981. Check out the LEO Computers Society.
Andrew Yeomans
You'd need to reduce Linux's total footprint to 1024 instructions+data with no swapping, no hard disk, no networking, and all I/O through punched tape, but within those limitations it should run just fine.
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.