PDP11/34a resurrection help

JP Hindin jplist2008 at kiwigeek.com
Sun Jul 26 17:28:21 CDT 2009

On Sun, 26 Jul 2009, Steve Maddison wrote:
> > on this header. Currently it looks like this:
> > BERG    DB9
> > B        5    GND
> > F        2    RX
> > J        3    TX
> > I -think- this is right, but I'm not positive. If I'm doing something
> > stupid, I'd sure love to have someone point it out.
> I built a cable like the adapter you're describing here for a DL11-D
> and it looks like the same sort of deal. For a terminal, I think you
> want RX and TX the other way around (unless you're using a crossed
> cable from your adapter to the terminal, of course). You also need to
> connect the "interlock" pins too (E and M for EIA/RS-232).

I've verified the DB9<->DB25 does not cross, so I have rewired, and
connected the interlocks (I'm not entirely positive what this does...?)

My new adaptor is:

Berg	DB9
F	3	TX
J	2	RX
E-.		Interlock bridged
M-~		Interlock bridged

Powering on the 11/34a gives me the same... nothing at all, but as I
suspect the 11/34a is halting somewhere, this is probably quite

My thanks, Steve, for getting me a little closer.

 - JP

More information about the cctalk mailing list