[TUHS] PDP-11, Unix, octal?

William Pechter pechter at gmail.com
Tue Jan 17 11:33:52 AEST 2017

And DEC used octal from the 1959 PDP1 through the VAX  which was 
announced on October 1977.

The PDP11 register front panel was painted to make front panel octal 
programming easier -  breaking out the three bit patterns.
Octal was deep in the DEC history and front panel flipping fingers.
I'll never forget 014747 (single instruction memory decrement test (move 
the pc to address pc - 2...


Steve Johnson wrote:
> The mainframes of the 60's and 70's all used 6-bit characters (and 
> often different encodings for the non alphanumeric characters). So the 
> Unix folks, including me, had experience with octal long before Dec.
> Steve
>     ----- Original Message -----
>     From:
>     "Warren Toomey" <wkt at tuhs.org>
>     Something I've been meaning to ask for a while: why Unix and octal
>     on the
>     PDP-11? Because of the DEC documentation?

Digital had it then.  Don't you wish you could buy it now!
pechter-at-gmail.com  http://xkcd.com/705/

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