Odd "endianness" [was Re: RE: Base 64 posts to the list]

Phil Budne phil at ultimate.com
Fri Dec 9 12:43:50 CST 2016

Rich Alderson wrote:
> There are also Two-Word Global Byte Pointers (which I've never seen
> abbreviated) which carry the standard "any size byte at any position"

Maybe they were just Global Byte Pointers?  OWG's were a late
addition.  I was a member of the FORTRAN-10/20 v10 project to make it
generate/run code in extended addressing...  It's tempting to look at
the compiler and FOROTS to see what terms we used a the time...

> Neither of those is entirely accurate.  9-track tapes on the PDP-10 used
> one of the following encodings:

8-bit characters became more important near the end of PDP-10 software
development.  ISTR TOPS-10 getting new 8-bit I/O modes, but I have a
vague recollection that translation between 36-bit words and mag tape
frames was handled by the "tape formatter" hardware, which means that
writing two words with 8 bit bytes in way that was easily legible on
8-bit byte oriented hardware ("high density mode" was only "legible"
for the even words).


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