Browse Prior Art Database

Work Station Controller Support for Pop-Up Windows Many Levels Deep

IP.com Disclosure Number: IPCOM000120606D
Original Publication Date: 1991-May-01
Included in the Prior Art Database: 2005-Apr-02
Document File: 4 page(s) / 112K

Publishing Venue

IBM

Related People

Eagen, ST: AUTHOR [+2]

Abstract

Described is a display data stream handshaking method between a work station controller (WSC) and host processor, such that the number of windows supported with windowing assist can be very large.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 41% of the total text.

Work Station Controller Support for Pop-Up Windows Many Levels Deep

      Described is a display data stream handshaking method
between a work station controller (WSC) and host processor, such that
the number of windows supported with windowing assist can be very
large.

      A WSC provides attachment of multiple non-programmable
terminals (NPTs) to a host computer system.  WSCs may support
windowing assist, where the WSC stores panel data which will be
overlaid by a window and overlaid entry field definitions when a
Create Window data stream command is received.  Then, when the window
is removed by a Remove Window data stream command, the WSC can
rebuild the panel and entry field definitions prior to the window.
However, WSC memory is limited and the number of windows supported by
windowing assist was fixed for a given model of WSC.

      The flow of a display data stream between a host processor and
a WSC, and NPT commands between a WSC and an NPT are shown in the
figure.

      An outbound display data stream (host to WSC) typically defines
a panel, and entry field locations and sizes for an NPT.  An outbound
data stream could contain Create or Remove Window commands.  An
inbound display data stream typically identifies the keystroke which
caused the inbound data stream and any modified entry field data.
The WSC communicates with the NPT by sending commands (for example,
write to screen move the cursor, or move screen data).  The NPT
communicates with the WSC by sending user keystrokes. Note:
Programmable Work Station (PWS) users can run the same applications
as NPT users when the PWS supports the same display data stream as
the above WSC and the PWS emulates the combination of the WSC and
NPT.  This article applies to a PWS implementation as well as a WSC
implementation.

      Described is a display data stream handshaking method between a
WSC and host processor, such that the number of windows supported
with windowing assist can be very large. Three WSC enhancements
improve the windowing assist function.
IMPROVED STORAGE MANAGEMENT DESIGN:

      An improved storage management design will be used for overlaid
panel data.  For example, if a given model of WSC guaranteed enough
storage for one pop-up window, 3564 bytes of storage are required in
the WSC for overlaid panel area (display screen in large screen mode:
27 rows by 132 columns = 3564 bytes).  Most windows are smaller than
the entire screen.  The improved design allows multiple-level
pop-ups, as long as the total overlaid panel area is less than or
equal to the WSC storage area allocated to the NPT (for example, 3564
bytes).  Currently, a maximum of 256 entry field definitions are
allowed per base panel and all levels of pop-ups.  If either a Create
Window command is received when WSC storage limits will be exceeded
or when more than 256 entry fields are defined across the base panel
and pop-ups, the WSC will negatively respond to the display...