🚀 go-pugleaf

After 2 marginally successful hours with a breakout box I would like to
solicit help from the net.  Here is what I am trying to do (and what has
been happening so far):

I want to hook the COM1 port of a PRO350 running Venix 1.0 up to a
Macintosh Plus running MacTerminal in VT100 mode, as a second terminal.
At the Mac Plus end is a Mac 512k peripheral adapter taking the MINI8 plug
to a DB9 and the DB9 goes into an 8 conductor RJ11, of which only the inner
6 are used.  At the PRO end is a DB25 from the 6 conductor RJ11.  The
pin connections are as follows:

	DB9		DB25		Signal
	===		====		======
	1		7		Signal Ground
	5		2		Transmit Data
	6		20		Data Terminal Ready
	9		3		Receive Data

(Pins 4,5, and 6 on the DB25 also appear to be active.  I tried various
combinations of tying them together or to gnd or high with no changes.)

I was expecting to have to flip 2 and 3 (null modem), but this was not the
case.  With the above configuration I could do:

	cat foo > /dev/com1

and the output would appear on the Mac, but editing /etc/ttys to make
com1 an active terminal and then forcing init to restart with 'kill -2 1'
as mentioned in the Installation and Maint. Manual failed to produce the
'login:' prompt on the Mac end.

So, it appears that I can send data from the PRO to the Mac, but not the
other way around.  Does anyone have any helpful suggestions on how to solve
the problem?

Thanks for your help,

Steve Leeke

-- 
Steven D. Leeke, Center for Integrated Systems, Stanford University
    {ucbvax,decvax}!decwrl!glacier!leeke, leeke@cascade.stanford.edu

"I suppose they don't use money in the 23rd century?"