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From:   Joseph Todaro
Sent:   Sunday, July 21, 1996 7:23 PM
To:     Multiple recipients of list HP3000-L
Subject:        Block mode  vs  Block heads  (with too many thumbs)
 
Hi to all you HP3000 gurus, I wonder if anyone can help me.
 
We have a 957RX with over 100 users using IMAGE and a swag of=20
in-house programs mainly written in HPBASIC V. (We have source)
 
One thing that has always concerned me is inexperienced users using =
Block Mode screens to update or add to Image data sets.
 
If the user presses any keys while the screen is drawing (and they =
usually do) it will result in a 'corrupt' screen draw. The boxes will =
all be in the wrong place with incorrect lengths !!!
 
<< snipped >>
 
Joe,
 
Two areas here - (1) using a terminal or (2) using a Termulator on a
PC (I've gotten lots of messages on that term - glad you all like it =
<g>)
 
If using an HP terminal, you should not be experiencing this problem,
as the keyboard is locked, and any input from the user, including
the pressing of f-keys is ignored.
 
If using a termulator such as Reflection/1, the same thing applies,
if configured as an HP terminal.  The keyboard is locked, and input
is ignored.
 
The only exception here is that if typeahead is turned on either on=20
the 3000 (using CI variables) or through the termulator, if it supports
it, then the keyboard input is cached until the 3000 is ready to
accept input, then the keystrokes are sent as buffered.
 
This is the VPLUS has always worked (assuming you're talking
VPLUS here).  If not using VPLUS, then you're on your own and=20
you will need to compensate for this in your screen driver code if
you're not using standard VT or DTC protocols, which will lock the
keyboard on 3000 output.
 
Hope this helps,
 
Best Regards,
Joe Geiser