You can direct the terminal to "hang up" the modem by sending an Et: f . The terminal accomplishes the modem dis- (--connect by lowering the TRICD (Terminal Ready) line for two seconds.
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INTRODUCTION
The display portion of the HP 2624B 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 offthe 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 cursor up, down, left, or right on the screen.
• 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.
• Thrn off screen display except softkey labels.
• 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:
When format mode is enabled, you may perform this func-tion programmatically but leave the cursor posifunc-tioned at the beginning of the first unprotected OR transmit-only field (whichever occurs first) by using the following escape sequence:
Home Down
Pressing the
l1li
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:
Move Cursor Up
Each time you press the _ key the cursor moves upward one row in the current column position. If you hold the key down, the cursor movement continues row-by-row until the key is released. When the cursor is in the top row of the screen, pressing this key moves the cursor to the same column position in the bottom row of the screen.
To perform this function programmatically, use the follow-ing escape sequence:
Move Cursor Down
Each time you press the _ key, the cursor moves downward one row in the current column position. If you hold the key down, the cursor movement continues row-by-row until the key is released. When the cursor is in the bottom row of the screen, pressing this key moves the cursor to the same column position in the top row of the screen.
To perform this function programmatically, use the follow-ing escape sequence:
EtB
A.
MEMORY
~J
DISPLAY SCREEN
MEMORY
lJ
ROLLUP
Move Cursor Right
Each time you press the _ key, the cursor moves one ( column to the right in the current screen row. If you hold . the key down, the cursor movement continues column-by-column until the key is released.
This function is performed without regard for existing margins. When the cursor reaches the rightmost column of the screen, pressing this key moves the cursor to the leftmost column in the next lower row (from the rightmost column in the bottom row of the screen, the cursor moves to the leftmost column in the top row of the screen).
To perform this function programmatically, use the follow-ing escape sequence:
Etc Move Cursor Left
Each time you press the _ key, the cursor moves one column to the left in the current screen row. If you hold the key down, the cursor movement continues column-by-column until the key is released.
This function is performed without regard for existing margins. When the cursor reaches the leftmost column of
B.
MEMORY
rJ
DISPLAY SCREEN
MEMORY
D
ROLL DOWN
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Figure 4-1. The "Roll" Data Functions 4-2
the screen, pressing this key moves the cursor to the rightmost column in the next higher row (from the leftmost column in the top row of the screen, the cursor moves to the rightmost column in the bottom row of the screen).
To perform this function programmatically, use the follow-ing escape sequence:
"eD
Roll Text Up
Each time you press the . . key, the text in display mem-ory rolls up one row on the screen. The top row rolls off the screen, the remaining data rolls up one line on the screen, and a new line of data rolls from display memory into the bottom line ofthe screen. If you hold this key down, the text continues to roll upward until you release the key or until the final line of data in display memory appears in the top row of the screen. In the latter case, pressing or continuing to hold down the key has no further effect. The "roll up"
function is illustrated in figure 4-1a.
To perform this function programmatically, use the follow-ing escape sequence:
Roll Text Down
Each time you press the • key, the text in display mem-ory rolls down one row on the screen. The bottom row rolls off the screen, the remaining data rolls down one line on the screen, and a new line of data rolls from display memory into the top line ofthe screen. If you hold this key down, the text continues to roll downward until you release the key or until the first line of data in display memory appears in the top row ofthe screen. In the latter case, pressing or continu-ing to hold down the key has no further effect. The "roll down" function is illustrated in figure 4-1b.
To perform this function programmatically, use the follow-ing escape sequence:
Next Page/Previous Page
The data in display memory can be accessed (displayed on the screen) in blocks that are known as "pages". Generally speaking, a page consists of 24 lines of data. The current page is that sequence of lines which appears on the screen at any given time. The previous page is the preceding 24 lines in display memory. The next page is the succeeding 24 lines in display memory.
If the memory lock function is being used to "lock" some number of lines on the display screen, then a page consists of the number of "unlocked" lines on the screen. For ex-ample, if ten lines of data are "locked" on the screen, the current page consists of the 14 "unlocked" lines visible on the screen. The previous page is the preceding 14
"unlocked" lines in display memory. The next page is the succeeding 14 lines in display memory.
The concept of display "pages" is illustrated in figure 4-2.
Figure 4-2. Previous Page and Next Page Concepts
Pressing the • key rolls the text in display memory up so that the next page of data replaces the current page on the screen. If you hold the key down, the operation is repeated until you release the key or until the final line in display memory appears in the top line of the screen. In the latter case, pressing or continuing to hold down the key has no further effect.
To perform the "next page" function programmatically, use the following escape sequence:
"eU
Pressing t h e . key rolls the text in display memory down so that the previous page of data replaces the current page on the screen. If you hold the key down, the operation is repeated until you release the key or until the first line in display memory appears in the top line ofthe screen. In the latter case, pressing or continuing to hold down the key has no farther effect.
To perform the "previous page" function programmati-cally, use the following escape sequence:
"eV
At the completion of the "next page" or "previous page"
function, the cursor is positioned at the left margin in the top line of the screen.