29 Jul
2004
29 Jul
'04
5:13 a.m.
If the answer is: a device that maintains the time of
day independent
of the computer power, the oldest I know of is the DEC KW11-W (?not
sure about the suffix). I don't remember when that came out, but it
probably predates microcomputers. It wasn't a popular option.
As I mentioned in another post, I think it was the KW11-C, and was a
unibus-only option. There was a KWV11-C, but I don't know if they
were associated. Early 80s.
BTW - this board also had batteries, so the clock would maintain
time across system power cycles (it charged the batteries when
the mains were on)
Another example, from roughly the same era, is the TOY
clock in the
Pro-350. That's a microcomputer chip, so presumably some PC type
system offered it as well. (That may apply to the KW11-W as well... I
don't know.)
It was separate from the actual CPU chip... it might have been
something like a Dallas chip, so probably someone else was using
it as well. Mid 80s.
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL,ST| email: mbg at world.std.com |
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| Chelmsford, MA 01824 | "pdp-11 programmer - some assembler |
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