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THE QUESTION ABOVE is grammatically correct: I intend “can,” not “will,” nor “may.”
Those of a certain age may remember asking, “Mrs. Grimbly, can I open a window?” She’d say, “Young man, whether you are able to do so isn’t the question. Were you asking my permission, you would say, ‘May I?’ “
But I stray from the point of today’s SimanaitisSays topic: Indeed, can I read a floppy? Or a cassette? Or a magnetic tape? Or a stack of punched cards?
Digital Storage. Media for digital data storage have evolved as quickly as the computers themselves. Here in Parts 1 and 2 today and tomorrow are tidbits about digital storage, ranging from magnetic tape and punched cards, through various means of floppy storage, to solid-state devices and the ethereal Cloud.
In the Beginning Was the Bit. At their most fundamental, digital devices are binary; either 0 or 1, electronically off or on. Most of us don’t readily work with long strings of 1s and 0s; or, as specialists manage, with other base 2n variations like hexadecimal base 16.
What’s more, early computers had volatile memories: Power off; memory gone. Storage depended upon reels of magnetic tape, rolls of punched paper tape, or stacks of punched cards.
Stacked Decks. Back in the early 1960s, Worcester Poly had its own IBM 1620, with which we’d work out programming details of a project. Then we’d take the stack of punched cards to Boston, where MIT maintained a large regional time-sharing mainframe. And, yes, the byword was “Do Not Fold, Spindle, Or Mutilate.” Such stacks were preciously transported.
R&T’s Cassette Memories. When I began at R&T in 1979, its Paul Lamar-designed computerized road test equipment had programmed instructions stored on two separate cassettes, one for acceleration testing, the other for brake testing.
Once loaded and operated, the equipment provided paper-strip output. Changing the equipment from acceleration to brake testing took several minutes, and woe be it if the cassettes got too hot.
Tomorrow in Part 2, we continue with more digital storage, eventually getting positively ethereal about it. ds
© Dennis Simanaitis, SimanaitisSays.com, 2021
Ah the joys of punch cards. In humid climates the cards would swell over time eventually causing jams in the card readers. A good plan was to get the card reader to duplicate a deck for a back up. It was a good idea to add the serial number on the ends of the cards (after column 72), and to run the cards through the key punch machine to add the text to the card, because you’d have a chance of reassembling the card deck if you dropped it.
While in grad school we had direct access to a research group’s reader/printer terminal connected to one of the campus main frames, rather than having to take our decks to a service desk and come back later for the print outs. Instead we would put our decks in the reader, punch a start button on the reader, then go to the console punch in a command and almost immediately the printer would start spewing out the output. One little caveat with the reader though; there was a counterweight on the output side and you had to make sure that the weight was all the way down. On more than one occasion I was in there and another person would come in, load up the reader and start the execution process only to hear a ratatat sound and look around to see a rooster tail of cards go flying across the room.
Ah yes, cards. My senior project deck may still be somewhere in the house (perhaps I’ll find it while we clear the place out for painting and floors). And what do you do when the project’s done and the deck is irrelevant? Remember punch-card curtains?
My first actual PC was a Radio Shack Model 1 that used cassettes for all storage. It came with a portable R/S cassette recorder that, if everything was tuned up just right it was fairly reliable, if slow. Later got floppy drives (5 1/4 single-side Teacs, indestructible) which worked well and (obtained in the sales area of a San Francisco Computer Faire) were much less expensive than those sold by R/S itself: about the same price for 2 as for 1 at R/S iirc.