backspace delays on 3B2 PORTS cards

[Stephen J. Friedl]

Netpeople,

     We've been running a 3B2/400 for a while and have been
through a number of releases of the operating system.  One chron-
ic problem is that PORTS cards (the ones with a parallel port
and four serial ports) seem to add delays when backspaces are
written.  Try this:

        $ echo "xxxxxxxxxxxxxxxx\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b"

and watch the cursor blow by the xxxxx and then move noticeably
slower on the backspaces -- I timed it at around 300 baud.
There are no backspace delays set via termio -- I wrote a hand-
full of little programs to open the port in absolutely *raw* mode
to no avail -- but I still get the delays.  If I set the high bit
the \b goes out quickly, and this problem does occur on the EPORTS
cards.

     I have seen this on every 3B2 I have been on and AT&T has no
answer for me.  Has anybody else seen this?  Any suggestions?
I've already rewritten some of my termcap/terminfo entries to use
alternate move-the-cursor-left strings but sometimes there are no
other ways than to use backspace.  Sigh.

     Thanks,
     Steve
-- 
Life : Stephen J. Friedl @ V-Systems, Inc/Santa Ana, CA    *Hi Mom*
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