I've had a bad and painful week and I've been re-reading some old fforum posts to take my mind off... stuff. I usually apologise after a post, but I'll apologise in advance this time. Ramble mode on, and...
Quote:Give me the Spectrum any day over the Amstrad
Why has nobody (that means me) mentioned the C=64? I bought my first one in 1982, and I still have it in working order.
And its 1541 Smart Drive, with the huge capacity 180k discs. I wrote 6510 machine code for the C=64 and when I bought my first NZ$20 180k disc I thought I had enough capacity to contain all the code I could write for the rest of my life. Huh. The machine I'm typing on now has...
Bugger. I thought I knew. Hang on, I'll have to run [www.belarc.com].
5980.63 Gigabytes Usable Hard Drive Capacity
3506.28 Gigabytes Hard Drive Free Space
Whoops. Just barely over 2 terabytes free. Time to add another drive.
O tempora! O Mores!
Why was it a smart drive, you ask? Aha, I answer, without the slightest trace of detectable condescension. The smartness was to do with the skillful way it preserved head alignment. You may recall that the floppy drive readers of that time (the 1980s) were very prone to losing accurate alignment very quickly. The 1541 was way ahead of the field in the way the head alignment was checked. "Huh," the head said. "I'm not quite sure just where I am at the moment. I know, I'll run head down as fast as I can towards that metal post over there. When I arrive (bang!) I'll know (bang!) where I am (bang!) and if I do it again (bang!) and again (bang!) and I bounce just the right amount (bang!) I'll know that I must be right at the post. Now I can go back to the right spot on the disc and load the last bit of that 8 bit sprite."
I feel like digressing. So I will. Instant gratification of wishes, that's what the Net is all about. I won't think about what I'm actually digressing
from because I'm easily confused.
I used to be amazed at the sheer speed and accuracy of that drive head whirring around and reading all those ones and zeros without ever getting it wrong, but then one day I read the specs and methods of the drive and I became even amazeder. (I was very young, not even forty. But I had the body of a thirty-year-old, in the basement refrigerator. Ha ha, gotcha! The fridge was in the garage.)
It turned out that the drive said it was 40% accurate. What it meant was:
First of all, the drive never wrote a zero. All it wrote was ones.
Blip! I wrote a one.
No blip! I never wrote nuffink.
Firstly it turned each binary number into a ... I forget the word. It meant that there would never be more than two consecutive zeros in any number. Then...
As the head spun round... well, the head stayed in the same place. The disc spun around. The head moved from track to track.
As things spun, the disc controller kept counting the time taken. Little second bits. Milli? Micro? Pico? Don't remember. Can't be bothered working out. It would come across a little bit of magnetised disc. "Aha! Got a 1." Moving on... I should have had a one by now. Didn't get one. OK, that's a zero. Still counting... no blips. Aha! Got one. Reset the counter, keep on reading.
You see how the blips make a one, and the waiting time looking for a blip without finding one make a zero? The 40% I mentioned was the allowable time
not to find a blip, meaning that the head had found a zero.
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And my USB3 drive transfers data at 600 megabytes per second.
My mind just boggles.
There just ain't nuffink wowier to say.
Sorry.