LP> Is there a way to null cable parallel to parallel between an
 LP> OS/2 unit & a DOS unit?

A "null-modem" cable can be used between the SERIAL ports of two 
computers.  I'm using an excellent DOS shareware program, ZIP202,
to interconnect computers in an elementary school library.  That
setup is all DOS (DR-DOS, AAMOF), but it should work fine in a
VDM session on an OS/2 machine.  In fact the author was asking
for people to test just such a setup at the time I was installing
it.  (I offered to test a CP/M to OS/2 setup for him, but he never
responded :)

BTW, ZIP202 has nothing to do with PKZIP.  Its full name is "ZIP:
Fast File Transfer Utility".  Its author is Eric Meyer, 3541
Smuggler Way, Boulder, Colorado 80303.  At the time I got it (about
1995) he was on line at Compuserve [74415,1305] or internet
74415.1305@compuserve.com.

The docs for ZIP202 are excellent, including specifications for
building your own null-modem cables in either 3-wire or 7-wire
configurations with 9-pin or 25-pin connectors--any combination.
Of course, ready-made null-modem cables are avilable commercially.

Jack P.
 
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