pdp11/93 DB9 rs232 pinout

Johnny Billquist bqt at update.uu.se
Sat Nov 15 15:33:59 CST 2014

On 2014-11-15 13:26, Johnny Billquist wrote:
> On 2014-11-14 17:59, drlegendre . wrote:
>> Wow..
>> On Fri, Nov 14, 2014 at 7:19 PM, Noel Chiappa <jnc at mercury.lcs.mit.edu>
>> wrote:
>>>      > From: Roe Peterson
>>>      > Can anyone point me at the pinouts for the KDJ11-E pdp11/93
>>> DB9 rs232
>>>      > connectors for the extra 7 (simulated) DL11s?
>>> Alas, documentation on the 11/93-94 seems to be very scarce on the
>>> ground.
>>> (And, just for grins, the page in the 11/94 User Guide which has the
>>> section -
>>> 1.2.6 - which talks, however briefly, about that panel - pg. 1-4 - is
>>> missing
>>> from all the online copies of that manual which I checked.)
>> Man, this is like deja-vu all over again..  at least I don't feel like
>> I'm
>> the only one in serial-pinout confusionland.
> Hmm. Interestingly enough I just searched through both the 11/93 and
> 11/94 manuals, which I referred to before, and neither actually seems to
> have the pinouts for the serial ports. Oh well.
> The console is on a DB25, with a very standard RS-232. I hope everyone
> can manage to get that one right.
> For the DE9 connectors, they actually also follow the RS-232 standard.
> For a connector without the modem control, all pins are in the first 9
> anyway, so no problem. If you want full modem control, there is one
> signal - DCD I think, which is on pin 20 in the RS-232 spec. On the DEC
> DE9, I think that one was moved to pin 8. But someone should check that
> out, in case they actually want full modem control.

And I just read Glen Slick's response about the pinouts, where he listed 
them fully. Apparently, DEC never did modem control on any of the ports, 
so it's just 2,3,7 which are useful anyway.


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