Reiability of wrong media (was: is out of 5-1/4" diskettes

From: Megan <mbg_at_world.std.com>
Date: Fri Jan 22 21:35:29 1999

>If so, how does 1474560 become 1.44M, not 1.47M?
>The only way is to mix the terms, and use 1024000 as a meg! That is
>NEITHER the power of ten, NOR the power of two. In addition, it is NOT
>what they then use to measure memory!

Heck, I don't know about PCs... they do strange things. In pdp-11
land, we all talked about powers-of-two for memory and disk space,
and knew full well that the actual count of bytes was going to be
different.

1 Kb is 1024 bytes. 64 Kb is 65536 bytes. 128 Kb was 131072 bytes.
and so on...

Worked the same way for disks... RT-11 architectural limit for a
disk volume is 32 Mbytes. That's

        65536 (blocks) * 512 (bytes)
        ---------------------------- = 32 Mb
              1024 * 1024

It all just seemed to work properly *in the ole days*, PCs screwed
things up... :-)

                                        Megan Gentry
                                        Former RT-11 Developer

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Received on Fri Jan 22 1999 - 21:35:29 GMT

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