First computer with real-time clock? - test-drb@ccmp.vtda.org

29 Jul 2004

...
 >I'm thinking farther back.  Was there any mini
or mainframe that had a
>real-time clock built in or as an add-on option? 
...
 It's come up in some litigation.  The actual issue
at hand is that
someone was able to overturn a patent by claiming the IBM 650 had a
real-time clock built in.  They "proved" this by submitting as evidence a
printout that had the date printed on it(!)  I've checked the IBM 650
Manual of Operation and it makes no mention whatsoever of a real-time
clock.  I pretty much figured it wouldn't but I of course had to do due
diligence. 
...
 But it made me wonder: what was the first computer to
have a built-in
real-time clock? 
The 11/93,94 has built-in date/time.  But that was end of 80s, early
90s.

Prior to that, the Pro series had the TOY (time of year) clock built in.
That was in the mid-80s.

Prior to that, at least with Unibus PDP-11s, CSS (Computer Special
Systems, DEC Nashua) came up with the KW11-C, a clock/calendar
board which, from the drawings I have, was supposed to eventually
be able to get its date/time from the WWVB signal.  Otherwise it
could be programmed with current date/time as well as date/time
for a future event which would cause an interrupt.  I have a
programming manual for it somewhere (in my proverbial deep
storage).  This was early 80s.

I seem to remember a KWV11-C, for qbus -11s, but I don't know what
its features were.

-- 

Sellam Ismail                                        Vintage Computer Festival
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