Table of Contents
Advertisement
Chapter 5. Programming considerations
Using the Window commands
5-58
You must define a window for each page of a partition. Windowing refers to
the movement of the window along the page. As the window moves toward
the beginning of the page, the data is moved down on the viewport. As the
window moves toward the left margin of the page, the data is moved to the
right on the viewport. The window can be moved up, down, left, or right on
the page by:
The Up, Down, Left, and Right keys
The host program sending the Set Window Position, Window Up,
Window Down, Window Right, and Window Left commands.
In addition, the windowing function is performed as a by-product of the
current cursor address (CCA) movement. For example, when an Insert Cursor
command from the host program moves the CCA out of the viewport, the
display station moves the window along with the CCA so that the cursor
remains within the viewport. This effect, in which a windowing action occurs
as a by-product of CCA movement, is known as auto-windowing.
Auto-windowing also occurs when the following keys are pressed:
•
CR, LF, VT, HT, and FF control code keys
•
Back Tab key
•
Tab key
•
Home key
•
Clear key
•
Erase Input key
•
Return key
•
Enter key
•
Send Message key
•
Send key
•
Send Line key
•
Graphic keys that cause the auto-skip function
•
Graphic keys at the end of the viewport
•
Graphic keys at the right margin of the viewport.
The following keys move the CCA within the window and the cursor within
the viewport without causing auto-windowing:
•
Backspace key
•
Cursor Up/Down keys
•
Cursor Left/ Right keys.
Use the Cursor and Buffer Address Table on page 5-80 to obtain the
parameter values (Prh, Prl, Pch, and Pcl) to be used in the Set Window
command.
Advertisement
Chapters
Table of Contents
