pdp11/93 DB9 rs232 pinout
henk.gooijen at hotmail.com
Sat Nov 15 11:15:04 CST 2014
Sent: Saturday, November 15, 2014 3:55 PM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: pdp11/93 DB9 rs232 pinout
On Sat, 15 Nov 2014, Noel Chiappa wrote:
>> From: Henk Gooijen
>> I wanted to connect a VT510 to the console port. All connectors are
> Really? The PDP-11/94-E User Guide (EK-PDP94-MG-001), available online
> in a number of places, shows (pg 46, aka 2-18) the Console/SLU panel,
> and the Console connector is much larger than the SLU connectors. (The
> illustration shows a 23-pin D-type connector - presumably an error, it
> should have been 25.) And here:
> is a picture of one, and it indeed has the 25-pin console connector.
> Although I suppose it's possible they changed the actual hardware at
> some point, and some real machines have a 9-pin D-type? Or maybe a VAX
> of some sort uses a similar panel, but with all 9-pin D-types, and
> someone had stuck on of those on that machine?
>> What worked for me is the "VAX console cable", in other words: that
>> DE-9 connectors is NOT "PC alike"! You can find the VAX console cable
>> pinout on the web.
> Good catch! It makes sense that the VAX and 11/93-94 use the same 9-pin
> D-type pinout; that way they'd only have to have one kind of cable.
If that's the case, then one could also use a H8571-B adapter with a MMJ
cable to connect the terminal. One thing to watch out for with the H8571-B
adapters though is that they are thicker than most of the other DB25 and
DE9 adapters such as the H8571-J, H8575-A, etc so you'd need the ports
further apart than typical if you wanted to use multiple adapters
side-by-side. The H8571-B I had laying on the desk is about 7/8" thick at
the MMJ connector and tapers down in an L-shape to about 5/8" thick at the
Oops, major mistake. You are correct, the console *IS* DB-25!
Bad memory, old age, who will tell?
But what I remember for 100% is that it is not as a PC!
I am going to the "hangar" this week, take the console cable so that
I can measure the connected pins and report back here.
- Henk, PA8PDP
More information about the cctech