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Display Control
Screen Relative Addressing
To move the cursor to any character position on the screen,
use any of the following escape sequences:
<tSC>&a <column number> c <row number>
Y
<ESC>&!! <row number> y <column number> C
<ESC>&!! <column number> C
<ESC'&!! <row number>
Y
where:
<column number) is a decimal number specifying the screen
column to which you wish to move the
cursor. Zero specifies the leftmost column.
<row number> is a decimal number specifying the screen
row to which you wish to move the cursor.
Zero specifies the top row.
When using the above escape sequences, the data on the
screen always remains unchanged.
If you specify only a <column number>, the cursor remains
in the current row. Similarly, if you specify only a <row
number>, the cursor remains in the current column.
Example: The following escape sequence moves the cursor
to the 20th column of the 7th row on the screen:
<ESC>&!!6y19C
Absolute Addressing
You can specify the location of any character within display
memory by supplying absolute row and column coor-
dinates. To move the cursor to another character position
using absolute addressing, use any of the following escape
sequences:
<ESC>&!! <column number> c <row number> R
<ESC>&!! <row number> r <column number> C
<ESC>&!! <column number> C
<ESC>&!! <row number> R
where:
<column number> is a decimal number specifying the
column coordinate (within display
memory) of the character at which you
want the cursor positioned. Zero specifies
the first (leftmost) column in display
memory.
<row number> is a decimal number specifying the row
coordinate (within display memory) of the
character at which you want the cursor
positioned. Zero specifies the first (top)
row in display memory.
When using the above escape sequences, the data visible on
the screen will (ifnecessary) be rolled up or down in order to
position the cursor at the specified data character. The
cursor and data movement will occur as follows:
• If a specified character position lies within the bound-
aries of the screen, the cursor moves to that position and
the data on the screen remains unchanged.
• If the absolute row coordinate is less than that of the top
line currently visible on the screen, the cursor moves to
4-4
the specified column in the top row of the screen and the
text rolls downward until the specified row appears in
c·
the top line of the screen.
• If the absolute row coordinate exceeds that of the bottom
line currently visible on the screen, the cursor moves to
the specified column in the bottom row of the screen and
the text rolls upward until the specified row appears in
the bottom line of the screen.
If you specify only a <column number>, the cursor remains
in the current row. Similarly; if you specify only a <row
number>, the cursor remains in the current column.
Example: The following escape sequence moves the cursor
(and rolls the text if neccessary) so that it is
positioned at the character residing in the 60th
column of the 87th row in display memory:
<ESC>&a86rS9C
Cursor Relative Addressing
You can specify the location of any character within display
memory by supplying row and column coordinates that are
relative to the current cursor position. To move the cursor
to another character position using cursor relative
addressing, use any of the following escape sequences:
<ESC>&!!
+/-
<column number> c
+/-
<row number> R
<ESC>&a
+/-
<column number> c
+/-
<row number>
Y
<ESC>&!!
+/-
<row number> r
+/-
<column number> C
<ESC>&!!
+/-
<row number> y
+/-
<column number> C
where:
<ESC>&!!
+/-
<column number> C
<ESC>&a
+/-
<row number> R
<ESC>&!!
+/-
<row number>
Y
<column number> is a decimal number specifying the relative
column to which you wish to move the
cursor. A positive number specifies how
many columns to the right you wish to
move the cursor; a negative number
specifies how many columns to the left.
<row number> is a decimal number specifying the relative
row to which you wish to move the cursor.
A positive number specifies how many
rows downward you wish to move the
cursor; a negative number specifies how
many rows upward.
When using the above escape sequences, the data will (if
necessary) be rolled up or down in order to position the
cursor at the specified data character. The cursor and data
movement will occur as follows:
• If a specified character position lies within the bound-
aries of the screen, the cursor moves to that position and
the data on the screen remains unchanged .
(
• If the specified cursor relative row preceeds the top line
(
currently visible on the screen, the cursor moves to the
specified column in the top row of the screen and the text
rolls downward until the specified row appears in the top
line of the screen.
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