DEC bus transceivers

Paul Koning paulkoning at
Mon Oct 24 15:41:04 CDT 2016

> On Oct 24, 2016, at 4:35 PM, Guy Sotomayor Jr <ggs at> wrote:
>> ...
> OK, I guess my last email didn’t make it.  It appears to me that the rise time is set at 25ns.
> You need to look at the PDP-11 UNIBUS Design Description document on Bitsavers.  Firstly,
> in section 4-1, it specifies which chips to use and recommends not using a whole list of other
> chips.  The only recommended chips are: 8640, 8641 and 8881.

Sure.  But we're trying to understand what is required in order to design alternatives.

Where do you see the 25 ns spec?  I didn't see it (admittedly in a quick scan).


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