Lots of Endians

Lots of Endians

[W. Wesley Groleau (Wes)]

> ... not only ... the Endian problem, but also the "which bit is lsb ..."

Even without the bit numbering question, there are more options than
Big Endian/Little Endian.

If you have byte-level addressing, there are 24 ways to store 16#89ABCDEF#

Most of them are probably never used, but unless my memory fails, I once
was forced to cope with (order of increasing addresses).

   AB 89 EF CD

or something like that.  Not really a major issue for integers.  What
made it a problem was in converting a floating point to IEEE-754 for
hand off to a 680x0/68882.  I know this is a job for assembly, but
we did it in Ada anyway.  It was rather irritating to have to separately
rep-spec two pieces of mantissa and reassemble them for output.

Then we discovered the disk IO swapped the bytes back, so we had to re-do
it the easy way after all!

(VAX/VMS if anyone cares)

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