[ih] "network unix"

[Scott O. Bradner]

> On Oct 9, 2016, at 2:36 PM, Jack Haverty <jack at 3kitty.org> wrote:
> 
> Hi Noel,
> 
> You're right, I should have said 32KW....but I wonder how many people
> today would know what "KW" means?  I suspect many would think it
> referred to the power that our ancient monsters consumed...actually
> probably not far off for the bigger machines that consumed many square
> feet of lab space!
> 
> The other aspect of the "Stone Age" that may not be remembered today is
> that a "byte" was not yet very well-defined back then.  PDP-8s had 8-bit
> bytes in 16-bit words.  


PDP-8s were 12 bit words

PDP-1, 7, 9, 15 were 18 bit words

PDP-11 were 16 bit words

PDD 6, 10 were 36 bit words

Scott

> Other machines made different choices.  The
> PDP-10 was agnostic -- the instruction set allowed the programmer to
> specify whatever byte size they liked.  So a "byte" only made sense in
> the context of a specific machine.
> 
> Today of course we all know that a byte is 8 bits.  Period.  Perhaps
> some historian can figure out exactly when that happened.....
> 
> Fun times...
> /Jack
> 
> On 10/09/2016 10:21 AM, Noel Chiappa wrote:
>> A few notes/corrections:
>> 
>>> The /40 design utilized a single address space for instructions and
>>> data, so everything had to fit in 32KB of memory (yes K, not M or G).
>> 
>> Err, that was 32KW, i.e. 64KB. But 8KB was the I/O page (device registers), so
>> only 56KB of memory - sort of, because V6 Unix used one 8KB page to map in
>> each process' kernel stack + other swappable per-process data, so really only
>> 48KB for all kernel code, data, disk buffers, etc.
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