Display Control; Introduction - HP 262SA Reference Manual

Display Control
INTRODUCTION
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The display portion of the terminal consists of display memory and the display screen.
Display memory is the portion of terminal memory assigned to contain the alphanumeric
data entered into the terminal for display on the screen. The display screen consists of 27
lines; each line contains space for 80 characters. The first 24 lines are used to display one
((page" of display memory, rows 25 and 26 display the function key labels, and row 27 contains
information on the terminals operation status.
On the HP 2625A, display memory is partioned into 2 workspaces, one each for the HP and
IBM personalities. At any given time, one workspace is active (that is, accessible for display
and for receiving data through the keyboard). The display cursor, a blinking underscore mark
on the screen or blinking inverse video box that indicates where the next character entered
will appear, is always present in the active window.
You can perform the following display control operations either locally from the keyboard or
remotely from a program executing in a host computer (these operations apply only to the
terminals HP personality).
• Move the cursor up, down, left, or right.
• Move the displayed data up or down in relation to the current cursor position (this is
referred to as (trolling" data on the screen). When a roll operation forces data off the top or
bottom edge of the screen, additional data rolls onto the screen at the opposite edge.
• Change the data displayed on the screen to the next or previous ((page" of data in the
workspace. A page is a sequence of 24 lines of data (the number of lines that can be
displayed on the screen).
• Set or clear a left and right margin.
• Set or clear one or more tab stop positions.
• Move the cursor forward to the next tab stop position or backward to the preceding tab stop
position.
• Enable or disable the inverse video, half bright, underline, blinking, and/or security dis-
play enhancements.
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