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INTRODUCTION
The display portion of the HP 2624A consists of a display
screen and display memory. The display cursor (a blinking
underscore mark on the screen) indicates where the next
character entered will appear. As you enter characters,
each is displayed at the cursor position, the ASCII code for
the character is recorded at the associated position in dis-
play memory, and the cursor moves to the next character
position on the screen. As the screen becomes full, newly
entered data causes existing lines to be forced off the
screen. Data lines forced off the screen are still maintained
in display memory and can subsequently be moved back
onto the screen.
You can perform the following display control operations
either locally from the keyboard or remotely from a pro-
gram executing in a host computer:
• Move the cur~or up, down, left, or right on the screen.
• Move the displayed data up or down in relation to the
current cursor position (this is referred to as "rolling"
data across the screen). When a roll operation forces
data off one of the edges of the screen, additional data
rolls onto the screen at the opposite edge from display
memory.
• Change the content of the screen to the next or previous
"page" of data in display memory. Generally speaking, a
page consists of 24 lines; if the memory lock function is
being used to "lock" some number of lines on the display
screen, however, a page consists of the number of
"unlocked" lines 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, un-
derline, blinking, and/or security display enhancements.
• Change from one character set to another (Roman, Math,
Line Drawing, and Large Characters).
In addition, you can do the following screen edit operations
either locally or remotely:
• Delete all characters from the current cursor position
through the end of display memory.
• Delete the line containing the cursor (subsequent lines
are rolled up).
• Change the line containing the cursor to all blanks.
• Delete the character at the current cursor position.
• Insert a blank line immediately preceeding (above) the
line currently containing the cursor.
• Enable or disable "insert character" mode. When this
editing mode is enabled, succeeding characters entered
through the keyboard or received from the host computer
are inserted to the left of the character at the current
cursor position.
CURSOR CONTROL
The following topics describe how to alter the cursor/data
relationship either manually by using the cursor control
keys or programmatically by using escape sequences.
Home Up
Pressing the _
key moves the cursor to the left margin
in the top row of the screen and rolls the text in display
memory down as far as possible so that the first line in
display memory appears in the top row of the screen.
When the memory lock function is being used to "lock"
some number of lines on the display screen, pressing the
_
key moves the cursor to the left margin in the up-
permost "unlocked" row of the screen and rolls the
"unlocked" text in display memory down as far as possible
so that the first "unlocked" line in display memory appears
on the screen in the row containing the cursor.
When format mode is enabled, the _
key also rolls the
text down as far as possible but leaves the cursor positioned
at the beginning of the first unprotected field.
To perform this function programmatically, use the follow-
ing escape sequence:
<ESC>h
When format mode is enabled, you may perform this func-
tion programmatically but leave the cursor positioned at
the beginning of the first unprotected OR transmit-only
field (whichever occurs first) by using the following escape
sequence:
<ESC>H
Home Down
Pressing the . . and _
keys moves the cursor to the
left margin in the bottom line of the screen and rolls the
text in display memory up as far as possible so that the last
line in display memory appears immediately above the
cursor position.
To perform this function programmatically, use the follow-
ing escape sequence:
<ESC>F
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