On Thu, 19 Jan 2017, Steve Johnson wrote:

> PCC ended up being ported to many dozen different architectures, so it's 
> quite possible, but I don't recall it being done.  It was kind of a 
> dinosaur by the early 70's.  I'm not even sure that it had memory 
> protection, and it certainly didn't have paging.  And the I/O system was 
> strange.  So porting Unix would have been next to impossible.

My memory of the Kyber (as we called them; we had a 72) was that it was 
not character-addressable, but 60-bit word-addressable, thus making string 
handling somewhat difficult.  Don't get me started on its utterly broken 
architecture...  I have thankfully lost my programming manual for the 
beast.

> The main thing I remember about the 6600 was that it didn't have parity 
> bits on its memory.  So people used to run the same program three times 
> and if two of the answers agreed, they published...

Parity only slowed it down, and besides, hardware never failed...

My fondest memory of the thing was its command completion; I would start 
to type "O, TR" and it would fill out "O, TRANSACTION TERMINAL STATUS".  
Which reminds me that my worst memory was its console keyboard, with "0"
on the left...
 
-- 
Dave Horsfall DTM (VK2KFU)  "Those who don't understand security will suffer."