Subject: Re: Need jumper settings for M7940/8017
To: None <,>
From: Carl Lowenstein <>
List: port-vax
Date: 09/22/1998 09:22:27
> Date: Tue, 22 Sep 1998 07:44:57 -0700
> To:
> From: Rick Copeland <>
> Subject: Need jumper settings for M7940/8017
> I have a pair of serial cards (M7940 and 8017) that I need to configure to
> RS232 from their current setup which I believe is a 20ma current loop.  The
> cards are from a pdp 11/03 that I have removed from my Vax 11/785. If
> someone has this infornatiom or knows of some Faq page where I can get
> could you please post it?

A quick tour through "Microcomputer Products Handbook" (1985) tells me
the following:

M7940 is otherwise known as DLV11.  It should have a jumper about 1/4 of
the card length in from the handle end, approximately centered side-to-side,
labeled EIA.  This will enable EIA (RS232) operation, assuming you have
the proper cable to connect to the 40-pin Berg connector.  There are also
four jumpers to the side of the 40-pin connector, labeled CL<1-4> which
might have 180-ohm resistors present if the board was set up to be the
active end of the current loop.  I don't think it hurts to leave them in,
since the BC05C cable for RS232 doesn't connect to the current-loop pins
on the Berg connector.

M8017 is DLVE1 formerly known as DLV11-E.  Best I can tell, it is EIA only.
It too needs the proper cable.  Presumably the same one as the DLV11.

Pinout data for the BC05C is buried much deeper, probably with my 11/40


        carl lowenstein         marine physical lab     u.c. san diego
        {decvax|ucbvax} !ucsd!mpl!cdl