VT100 termcap extras

[Chuck Forsberg WA7KGX]

In article <152 at mkunix.DEC.COM> tyager at mkunix.DEC.COM (Tom Yager) writes:
:I spent a good deal of money on a Visual 603 terminal (nice, by the way)
:only to find that it performed poorly in vi. Specifically, delete line
:put up the "@" character instead of deleting, insert line repainted the
:entire screen each time, and insert character redrew everything to the
:right of the cursor. Some of this was just annoying at 9600 baud, but
:someone dialing in & trying to use "vi" could have some real problems.
:
:I added the following entries the the standard SCO termcap entry for the
:VT100. I've tested them and checked DEC documentation to see if these
:features are also available for the real VT100: they are. Your terminal
:may require delay settings on some of these. Here's the new entries:
:
:   al=\E[L:dl=\E[M:dc=\E[P:im=\E[4h:ei=\E[4l:mi:
:
:If you're using a VT100 emulation, be wary of the "im" and "ei" entries
:above--your emulation has to be pretty tight to support these. If you
:have problems inserting characters in 'vi' after making these changes,
:remove the "im" and "ei" entries and try again.
:
:-- 
:Tom Yager, Digital Ultrix Support ("It MUST be the hardware!")

I'm not sure that those screen controls are part of the basic VT100
set.  The DEC "Terminals and Printers Handbook" shows them starting
with the VT101.

Tom is correct in observing that one's terminal emulation must be
"fairly tight" to work with this termcap speedup.  Pro-YAM and ZCOMM
work just fine, but Procomm Plus Test Drive went crazy when I tried
it at 9600 bps on an 8 mHz AT clone.

In order not to break Procomm, I'd suggest adding a "vt102" entry
(assuming you don't already have one) as follows:

vt102|dec vt102:\
	:al=\E[L:dl=\E[M:dc=\E[P:im=\E[4h:ei=\E[4l:mi:tc=vt100:

That defines the new features and uses the "vt100" entry for the rest.

Chuck Forsberg WA7KGX          ...!tektronix!reed!omen!caf 
Author of YMODEM, ZMODEM, Professional-YAM, ZCOMM, and DSZ
  Omen Technology Inc    "The High Reliability Software"
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