On Thu, 2007-05-24 at 11:38 +0100, Alan Cox wrote:
> > The DEC KAL10 stored 5 characters in a 36 bit word with one bit
> > left over for anything you wanted to do with it! It used 7 bit ASCII,
> > of course.
>
> Or 6 BCD characters or 4 8 (as 9) bit ASCII values. Ditto the Honeywell
> L66. Character width as a compile option.
>
> Be very glad that today you don't have to fight that kind of thing. Don't
> however assume in portable code that int is 32bits, long is 32bits,
> pointers are 32bits and so on. C99 has proper types when you need to be
> specific.
>
> Also be aware that some Linux ports have char as unsigned by default and
> others as signed.
Hi, Alan,
I haven't seen a signed char since the 80's. I did run into it once
on I think a ColecoVision package (don't ask!).
That would really mess up any algorithm parsing into memory, and
would make dealing with solving some kinds of memory issues very
difficult, I would think, although
most compilers will support an "unsigned byte" type or explicit cast of
(unsigned) charvar. The code would be explicit, but really ugly. As if
any algorithm that directly messes with memory is "clean".
I have written algorithms that needed to map memory for data base
use on a character/bit means, used to decode file resident data. What
heart burn this simple change
would make from that I don't even want to contemplate.
I do remember EBCDIC, and Bi Quinary encoding, along with 7 bit
characters (the old teletypes gave us that one with no lower case, and
BASIC still keeps that do to what I call hystorical reasons, hys for
hysterical and torical from historical for funny history, in view of
what we know today.)
I also remember data entry, keypunch, cardsorters, paper tape, mylar
tape, cartridge drives, a disk stack that was 5' high and 4' in diameter
that held something like 50 Mbytes. Not fondly either in view of the
power of my desktop. And god forbid, CRT memories and drum memories.
Oh, and everybody's favorite, core memory.
It has been a long and interesting road. Today, with memory cheap
as dirt (comparatively) and processing speed and power millions of times
greater (my first PC ran at 650Khz), I don't miss or wax nostalgaic. I
keep my Altair around just to show my grandkids someday.
Remember the saying "If you can't do it in 4K and 12 bits who
cares?". PDP, I think.
The first collection of mainframes I saw were 4 IBM 360's, one was
the overseer I think we called it, and the other 3 were redundant
processors. How is that for overkill.
Sorry for running on a bit. Maybe I do wax nostalgic.
Regards,
Les H
