29 Jul
2004
29 Jul
'04
5:44 a.m.
On Thu, 29 Jul 2004, Andy Holt wrote:
Certainly during the era of PDP-11s, DEC had a number of possible solutions,
though our lab never used them. Instead we used the Digital Pathways TCU
series. For example, see the manual for a Unibus board:
<http://dundas-mac.caltech.edu/~dundas/retro/tcu-150.pdf>
We used these in several 11/55s:
<http://dundas-mac.caltech.edu/~dundas/retro/tcu-trans.pdf>
There were also Qbus versions:
<http://dundas-mac.caltech.edu/~dundas/retro/tcu-50.pdf> and
<http://dundas-mac.caltech.edu/~dundas/retro/tcu-50qd.pdf>
See this for more information:
<http://dundas-mac.caltech.edu/~dundas/retro/tcu-lit.pdf>
Granted this was probably well after the IBM 650 (I'm not familiar with that
machine).
Hope this helps.
John
If you mean a clock that maintains time when
power is off or gets the time
by radio then we are probably into the micro era.
Yes.
But I can't imagine there was not a real-time clock (i.e. as described
above) as at least an option for an earlier computer system.