[vcf-midatlantic] Is there a RTC for a PDP-11?

Dave McGuire mcguire at neurotica.com
Sun Mar 3 01:11:08 EST 2019

On 3/2/19 3:27 PM, Richard Cini via vcf-midatlantic wrote:
> Ok, this might be a stupid question, but is there an eqivalent of a battery-backed time-of-day clock on the PDP-11? I know that it has a LTC signal on the bus which gives basic timing, and RT-11 has both date and time commands which aren’t retained through power cycles. It reminds me of the early PCs when there was no real TOD clock board.
> I found an M7952 real time clock board, but that looks more like an interval timer board. I also found the M4002 board but that seems like the same thing.
> Thanks!

  Codar made a nice one for Qbus for a long time; I don't know if they
made a Unibus version.  They pop up every now and then, I've seen them
on eBay.  I have a couple if you get desperate.  There is software for
them in the DECUS archives, etc.


Dave McGuire, AK4HZ
New Kensington, PA

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