Computer Recollections

Some snippets from the memory hole...

Punch Cards -
This may specifically date me, but in high school around 1976, we did a brief lesson series on computers. This involved learning some BASIC commands, writing them out on a piece of paper, and then filling out punch cards with number two pencils to run through the card reader to see if our programs would run. The school computer itself was in a separate room upstairs near the back stairway, across from the science room where the "computer club" met. Mostly, it seemed they specialized in generating ASCII art, but I digress.

The computer itself had a terminal, which allowed you to input command lines. This was regarded as the "slow" way to work, as you had to type in the BASIC commands, then RUN them. With the card reader, which was a separate beast, you could put the cards in the hopper and push the go button, running batches of different commands which would generally fail in ways you had not considered.

Technologically, we were comfortably "off the back", but didn't realize it.

Memory -
The Apple II that we were using had 64K of RAM. This was used for music sequencing, which meant that the MIDI data - i.e. keystrokes from the synthesizer - used up the available memory. The Roland MUSE software had a handy memory "bar" which decremented as you pressed keys. This meant a 3 minute song was pretty much pushing it, less if you used the "bender".

The Macs had 128K out of the gate.

By the time I bought mine, it came 512K of RAM, which I upgraded to 1 megabyte pretty quickly. Because I lacked the loooong screwdriver necessary, I had to have the local Mac shop do the dirty deed.

The early Macs used these cool small discs in a hard plastic shell, as opposed to the big 5.25" "floppy" disks that the IBM's used (see "Wargames" for reference"). They were single sided, which meant that they held something around 400K. Actual usable space was a little less, as you had to format the buggers.

Then they added usability for the other side of the medium. Voila - the DS (Double Sided) disk! 800K! Now we're talkin'!

Then they started writing a little tighter on the disk, increasing the density. Soon we had DSHD, giving you a stunning 1.4MB of storage on a single disk.

The Hard Drive Connundrum -
Most of my friends have suffered through this story, now it's your turn:

The big upgrade for your Mac was a second disk drive. That way, you could leave the program disk in the computer, and have your data disk in the second drive. Then you wouldn't have to do the dreaded "disk swap", as the Mac spat out whichever disk you fed it, requesting the other, as it appended the 12K or whatever of data to the file, and did whatever checksum the program disk required.

About this time, you could buy an external hard drive (or an internal one, but remember, the first Mac's were convection cooled, so this meant attaching a fan as well, or watching your computer get reasonably warm...). This was not a cheap endeavour, and the difference between the 10mb and the 20mb may have been a couple hundred bucks, IIRC. At least a hundred, which was worth more back then anyway.

So, one of my friends was considering this, and after much thought and conversation, he decided to get the 10MB, which was likely to be more than he'd ever need. I mean, just what would you do to fill up a 20MB hard drive?

The Stuck Hard Drive Fix -
The early hard drives were finicky beasts, of course. Some made you mechanically park the heads before you moved them. The other quirk that most shared was that the grease used on the drive system for the heads would tend to solidify, after a while preventing the head from moving out over the platter. It would sit there and "click-click-click" as it tried to start.

The fix was to start up your drive, and when you heard the "click", give it a hard whack. This would jump the head past the obstruction. It would often work, though it was generally agreed that this was then a good time to backup the drive (to floppies.... oy...) and then never turn the drive off again.




More as I think of things...

This is a work in progress. If you have ideas or feedback, please feel free to email me.

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updated: December 31, 2006


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