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Space Bar
A space is considered an actual character that occupies a
position or location on the face of the screen. When the
space bar (Figure 2-11) is pressed in upshifted mode, a
space code or blank is entered on the screen and will
replace whatever character is presently in that position (a
space can never be inserted in place of a protected character
when the keyboard is in the upshifted mode). The space bar
can be used to cause cursor advancement to the right,
through unprotected positions, if the keyboard is in the
down shifted position (SHIFT key down). If a space is
desired at a position occupied by any unprotected character
other than a NULL code, the keyboard must be upshifted.
Remember, in upshifted mode the space bar replaces all
unprotected positions with blanks (space codes). In down-
shift mode, the space bar will advance the cursor without
altering data except NULLS. The space bar has typamatic
action.
Figure 2-11. Space bar
Local Function Keys
These keys (Figure 2-12), the third of the four main groups,
cause movement of data characters or cursor within the
attachment but they do not cause an interrupt request. The
keys in this group are:
TAB (forward)*
TAB (backward)
New Line Cursor*
Up Cursor*
Down Cursor*
Left Cursor*
Right Cursor*
DUPL/DUPC*
Erase EOL
EOS/EOF
INS Mode
DEL Mode
Reset
*These keys are typamatic keys.
Figure 2-12. Local function keys
Cursor Positioning Keys
---I
Tab
___ Move cursor left
----l
New Line
-
Move cursor right
t
Move cursor up
I -
Back tab
~
Move cursor down
Figure 2-13. Use the cursor control keys to reposition the cursor
Because the position of the cursor determines where the
next character keyed will be entered, it is important to
know how to move the cursor to any location on the screen.
The operator will want to be able to move the cursor
around quickly to positions where data is to be entered or
altered. These keys are part of the Local Function keys.
They provide a means of rapid positioning of the cursor to
any character position without affecting any of the
information already on the screen. Cursor positioning keys
(Figure 2-13) move the cursor in a horizontal (right or left)
or vertical (up or down) direction.
e
Tab (forward)
G
Tab (Backward)
Figure 2-14. Tabulator keys
Tab (Forward). This key (Figure 2-14-A) causes the cursor
to skip to the right to the first position of the first
unprotected field it encounters; then, in typamatic mode,
skip to all first character positions of unprotected fields
encountered line-by-line in a left-to-right, top-to-bottom
movement. The first position of an unprotected field is
the first position encountered after a protected position.
On reaching the bottom right hand corner of the screen, it
wraps to the upper left corner of the display screen. On
a display with no unprotected fields, the cursor is
repositioned to character location zero.
Operation and Instruction
2-5
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