HP 3000 Manuals HP 3000 Manuals
HP ALLBASE/QUERY Enhancements
by Victor Veres
Australian Software Operation
This release of HP ALLBASE/QUERY is identical to the XL 1.2 (B.00.02)
Release, with the addition that it supports new functionality offered by
SQL D.0.
HP ALLBASE/QUERY (previously known as HP Visor) features a user interface
modeled after HP ALLBASE/4GL. This interface provides a high level of
user interaction, field-based editing and full use of terminal features.
It also helps achieve a common "look and feel" with HP ALLBASE/4GL, so
the two products may be used together in complimentary fashion when the
need arises. The fundamental design principle for the user interface is
the WYSIWYG (What You See Is What You Get) philosophy.
The main features of the HP ALLBASE/QUERY user interface on MPE XL can be
summarized as follows:
* The display always provides an accurate reflection of the actual
input (that is, a WYSIWYG interface).
* Field editing and terminal features such as insert character and
delete character are available.
* HP ALLBASE/QUERY can display messages, and accept user responses via
a message "window" at the bottom of the screen.
* Excessive system input and output load is avoided since the user
interface does not use character based I/O.
This article describes the techniques used to obtain the required user
interface functionality on MPE XL.
FIELD MODE OPERATION
To satisfy the user interface requirements, the MPE HP ALLBASE/QUERY
product uses a "field mode". In this mode, user input is transmitted on
a field-by-field basis when the field is "committed". A field commit is
generated by the user pressing RETURN (end of record), or by pressing TAB
(alternate end of record). This implies that all user input must be
terminated by one of the above two characters. In this sense, user input
includes cursor motion, backtab, and commands such as screen redraw
(CONTROL L) and screen printing (CONTROL P).
Since HP ALLBASE/QUERY does not operate in block mode, the ENTER key is
not supported. Instead, HP ALLBASE/QUERY uses a function key to allow
the user to terminate a screen.
DISPLAY HIGHLIGHTING
HP ALLBASE/QUERY provides a mechanism to specify the display enhancements
(such as inverse video, flashing display, or underlining). Highlighting
and color attributes may be specified for screen elements such as input
fields, text literals, display fields, error, and messages. This
mechanism is utilized when HP ALLBASE/QUERY is started from within HP
ALLBASE/4GL to inherit HP ALLBASE/4GL's settings - this contributes to
the common look and feel.
TERMINAL REQUIREMENTS
HP ALLBASE/QUERY requires at least the terminal functionality provided by
the HP 2622 terminal.
HP ALLBASE/QUERY uses terminal format mode to create "input" fields on
the screen. This ensures that the user can only enter or alter data in
the current input field.
Using protected fields enables the user to edit the data already in a
field. This approach avoids performance limitations due to excessive I/O
traffic associated with character mode, while still preserving the
WYSIWYG philosophy of HP ALLBASE/QUERY.
Supported Terminals
The current release of HP ALLBASE/QUERY supports the following terminals:
* HP 2622 to HP 2628,
* HP 239x,
* HP 700/9x,
* HP 150
* HP Vectra PC (With terminal emulation software)
Terminal Communication System
HP ALLBASE/QUERY uses a terminal communication system that is similar to
the HP-UX terminfo system. This system uses a number of terminal
capability files to determine the available terminal functionality and to
drive the terminal. Terminal capability files for all supported terminal
types are supplied with HP ALLBASE/QUERY. These file are in the
TERMDATA.SYS group.
HP ALLBASE/QUERY uses an MPE XL variable to identify the terminal. This
variable can be set by the command file used to start HP ALLBASE/QUERY,
or by a log-on UDC.
The HP ALLBASE/QUERY terminal capability files support all the normal
display enhancements and features provided by HP terminals, including the
line-drawing character set, color, and touchscreen operation.