On Mon, 17 Aug 2009 17:23:29 -0700 Walt Pawley <w...@wump.org>
> At 4:44 PM +0200 8/17/09, Heiner Strauß wrote:
> >Putting the symbol names in one word helped the linker / loader a lot.
> >Live was so easy.
> >C (one word = 32 bit) .NOT. (some word processor software)
> As something of an ancient curmudgeon these days, I've enjoyed
> this discussion. As speculation on my part, perhaps the six
> character limitation is less a software issue than an early
> architecture issue - DEC's PDP-6/10 design used 36-bit words
> and packed six characters (clearly from a limited subset of the
> then current ASCII) per word, making simple searches very
> effective through symbol tables with a simple word level
> compare loop.
Can I play in the ancient curmudgeonly nostalgia reunion too?
> While likely not all that closely related to the issue, I
> recall a technique I was introduced to on Control Data systems
> called COSY, in which one punched binary coded Hollerith cards
> with two characters per column encoded (six bits per
> character). Of course, such cards required excellent handling
> equipment (which Control Data had) because a stack of cards
> punched with 960 holes in each one had lots of opportunity for
> hanging chads.
First real systems programming job was converting $multinat's data files
from NCR 315 format (12-bit 'slabs' holding 2 6-bit alphanum upper-case
characters or 3 4-bit BCD numbers, on 7 track tape and some paper tape)
to IBM 360 format (8 bit EBCDIC chars or BCD numerics, on 9 track tape),
which only took about 4 months, replacing a whole floor & tons of gear.
The NCR was also clearly designed around 80-column punch cards; 2 alphas
or 3 digits or one 12-bit instruction code per column. The programmer's
art was judged (by peers, not management :) on what your best single
card 80-slab program could do once booted .. test runs of which involved
turning up at the end of The Operator's shift and likely offering some
$inducement, after conning one of the punch girls into typing 160 chars
of utter gibberish for no apparent reason ..
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