Triprocessor PDP-10 [Was: Re: [multicians] Emacs humor]

Rich Alderson RichA at
Fri Dec 4 17:53:10 CST 2015

From: Johnny Billquist
Sent: Friday, December 04, 2015 2:11 PM

> On 2015-12-04 21:52, Phil Budne wrote:
>> Rich wrote:

>>> [1] "Tops-10" was simply a renaming of an operating system which began on
>>>      the PDP-6 in 1964 and continued in an uninterrupted line of
>>>      development up through the final release, Tops-10 v7.04 (1988), and
>>>      maintenance (v7.05, 1993).

>> Are you sure about the captialization "Tops"?
>> I thought TOPS-10 ran on the DECsystem-10,
>> while TOPS-20 ran on the DECSYSTEM-20.

> Rich is correct. It's "Tops-10", but "TOPS-20". Water under the bridge...
> I can't remember the correct capitalization of DECsystem, though. Maybe 
> that too differed?

Both DECsystem-10 and Decsystem-10 appear in DEC documents of different dates,
the latter possibly appearing in non-LCG documents.


Rich Alderson
Vintage Computing Sr. Systems Engineer
Living Computer Museum
2245 1st Avenue S
Seattle, WA 98134

mailto:RichA at

More information about the cctech mailing list