[comp.sys.dec] Need help with DL11-W to RS-232 interface for PDP 11/04

immelman@phoenix.pub.uu.oz.au (John Smeh) (02/05/91)

	I am having problems with wiring a DL11-W so i can hook up a dumb terminal to it (rs-232).

	So far on the terminal i've wired pins 4-5, 6-20-8...and pins 2 and 3 to recieve/transmit on the serial card...

	Now, i have tested it with an led, there is a signal going out, and a signal coming in, BUT nothing comes up on the monitor!?



	Thankyou...


	John Smeh.

	"It's hard reinventing the wheel"


-- 

 smart: immelman@phoenix.pub.uu.oz.au                John Smeh
                                                     Melbourne, Australia.
 "And I feel it burning in my soul, And I wont let go..." - Debbie Gibson.

frisbie@flying-disk.com (Alan Frisbie) (02/06/91)

In article <1991Feb5.021612.2354@phoenix.pub.uu.oz.au>, 
immelman@phoenix.pub.uu.oz.au (John Smeh) writes:

> I am having problems with wiring a DL11-W so I can hook up a dumb
> terminal to it (RS-232). So far on the terminal I've wired pins 4-5,
> 6-20-8...and pins 2 and 3 to receive/transmit on the serial card... Now, I
> have tested it with an LED, there is a signal going out, and a signal
> coming in, BUT nothing comes up on the monitor!?

I just took a look at my DL11-W (M7856) and the cable I am using.
Since the board can handle both 20 ma and RS-232, there is a jumper
you need to insert to tell the board which signal to use.   Other
than what your terminal may require for control, the only lines
needed are transmit & receive data and logic ground.

In this view, it is assumed that you are holding the board as
follows:

                                            ____________
Edge               (Component side)        | Berg conn. |  /|
connector -->  ============================================_|  <-- Handle
                     (Etch side)


   +-------------- Ground (Logic ground, terminal pin 7)
   |
   |       +------ Serial (RS-232) Out (to terminal, normally pin 3)
   |       |
   |       |   +-- Serial (RS-232) In  (from keyboard, normally pin 2)
   |       |   |
   |       |   |
   B   D   F   J   L   N   R   T   V   X   Z  BB DD FF JJ LL NN RR TT VV
   A   C   E   H   K   M   P   S   U   W   Y  AA CC EE HH KK MM PP SS UU
   |       |           |
   |       |           |
   |       +-----------+   <--- Very important jumper!
   |
   +-------------- Ground (Optional chassis ground, terminal pin 1)

The pin designations are DEC's, and not the 1-40 designations we normally
use.   You will find them molded into the top of the Berg connector on
the board.   Pin VV is what we normally call pin 1.   DEC's connectors
sometimes have an extra blank pair of holes at each end of the connector 
(for a total of 44 holes), so be careful when counting.   These blank 
holes should not be counted.   The connectors that have these are the
ones which accept single wires, rather than ribbon cable.

Send mail if you have any problems.

---  Alan E. Frisbie                    Frisbie@Flying-Disk.Com  (Preferred)
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