malloy@ittral.UUCP (William P. Malloy) (05/01/85)
We have been having a great deal of trouble getting TANDEM to work on a VAX 780
running 4.2bsd. Basically it doesn't work. In particular our attempts at
uploading from an HP-64000 development system, and an ITT XTRA (IBM PC clone)
DO NOT work using flow control. Inserting a data scope on the RS-232 line
shows that data gets sent, but when overflow is reached the VAX doesn't send
back a ^S it just stops accepting input. Causing massively truncated and
munched on files. This problem also occurs when some people try to copy files
from our machine to another 4.2 VAX using tip and ~p and ~t.
The solution for the XTRA was to get the software to wait after each line is
sent for the VAX to read it. Slow but it works. With the HP-64000 that
can't be done. We've slowed the link all the way down to 1200baud from 4800
and we still have problems during the day. The uploading seems to work fine at
night when there's no load on the system. We think it's one of two problems.
(1) TANDEM works, but too slowly to be any good except on an unloaded machine,
or (2) TANDEM doesn't work, but it's happens not to be needed on an unloaded
machine.
The answer I suspect is one of:
1) Oh that's easy, you just have to invoke it this way..... (I HOPE!)
2) Everybody knows how to fix that bug, its.....
3) Tough luck, it just don't work. (I'm beginning to suspect this is the answer)
For Your Information:
Our machine is a VAX-780, with 64 Emulex DH port, 16 ABLE DZ, 16 DEC DZ ports
two Lasers at 9600, 1 1000-lpm parallel lp, 1 600-lpm parallel lp, 2 600-lpm lp
@ 4800, and 2 Qume printers @ 4800, plus an Interlan Ethernet board, all in
one UNIBUS box (I know not too bright but no one asked me).
--
Address: William P. Malloy, ITT Telecom, B & CC Engineering Group, Raleigh NC
{ihnp4!mcnc, burl, ncsu, decvax!ittvax}!ittral!malloy