1 Feb
2022
1 Feb
'22
2:57 p.m.
On 02/01/2022 4:08 PM Chuck Guzis via cctalk
<cctalk at classiccmp.org> wrote:
Good grief, it took DEC all that time? CDC was doing
it in the 1960s.
Had to, because of the wide variety of RMS available. I think that
one of the early 2311 clone drives (854?) used 256-byte (8 bit byte)
hard-sectored media, which isn't very friendly to systems with 60 bit
words. I recall that several sectors were used to create a logical
60-bit word addressable sector, with a substantial part of the last
sector of a logical PRU left unused.
--Chuck
LTA predates that considerably and is the earliest I am aware of.
LTA (Logical Tooth Addressing) was created in the 1850's by Babbage to avoid the
"shaft, gear, tooth" addressing he had been using in his "store." The
teeth of all gears were numbered sequentially (starting at 0 of course) across all the
gears and shafts. He even kept a few spare gears in a drawer for wear leveling.
It's believed the idea actually originated with Ada since it made her task much
easier.
Will