Sputnik, spaghetti and the IBM SPACE machine
The 50th anniversary of the 1401
No spaghetti for you
For decades, electromechanical accounting machines had processed data stored on punchcards - literally pieces of paper with holes in them. And since the early years of the 20th century, such machines had been programmed via plugboards, arrays of wires and wire-jacks.
"We have an image here of a fairly simple control panel," Branscomb deadpans, pointing to a mass of interwoven wires on a screen behind him. "They looked like a bunch of spaghetti, but this is how you controlled the machine in those days."
When Underwood laid eyes on the WWAM's plugboard - which accounted for nearly half its cost - he was, in his own words, appalled. "It was huge - it had to be," he says. "And all the electronics that drove the panel did nothing but that. They didn't help the customer solve his problem. They just drove the control panel."
The SPACE Machine would take a very different path. "I said 'From now on, no more control panels. We can use the money in a much better way,'" Underwood explains. "We could go to the kind of technology we saw in the large scale binary computers, go to a stored program." In this way, programming could be treated like native logic. "It could be manipulated and executed at high-speed."
Underwood calls the SPACE machine "my own little project. It could sit there and I could hug and pat it, slice it and dice it, and do anything I wanted to do. Nobody was telling me what to do." But in the wake of the WWAM's demise, it would become much more.
Joined by the 1402 (a card reader) and the 1403 (a printer), the 1401 was announced to the world on October 5, 1959, just two years - to the day - from Branscomb's Paris Sputnik meeting. The first unit shipped in September of the following year.
Clock speed: 87 kilohertz
Weighing four tons and consuming 13 kilowatts of power, 1401 machine included 500,000 separate components. Borrowing the WWAM's data path design, it was one of IBM's earliest transistor-based machines, with discrete germanium alloy-junction transistors designed by Big Blue and eventually built by Texas Instruments.
Made up of 2,300 printed circuit cards - each about 2.6-inches wide and 4.5-inches long - the core processor ran at 87 kilohertz. Core memory was no more than a stack of donut-shaped magnets circling tiny wire threads, and it stored somewhere between 1,400 to 16,000 positions, each holding 8 bits of data.
The 1403, the 1402, and the 1401 - with a tape drive
Machine-level programming was handled through a language dubbed Autocoder, but compilers were soon added for Cobol and Fortran. Though there was no operating system per se, Big Blue did provide a library of input and output utilities, and for later units equipped with tape drives, the company offered sort and merge programs as well.
The typical 1401 sold for around $500,000 - roughly $3.4m in today's dollars. But you could rent one for a mere $6,500 a month.
For some, Fran Underwood's SPACE machine wasn’t the most important IBM system of the 60s. The System/360 mainframe played Apollo to its Mercury. But as Charles Branscomb puts it: "The 1401 made a huge contribution to the 360. It paid for it."
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