3278 Operator Information Area - IBM 3270 Operator's Manual

• Cursor wrap works the same way on the 3278 as it does on the 3275/3277.
However, since your 3278 may use two different screen formats, keep in
mind that the cursor wraps
(1)
horizontally at the first (left) and last
(right) positions on the line and (2) vertically at the top and bottom lines,
not at the left and right or top and bottom of the screen.
• When the program updates the screen on the 3275 and 3277, the display
image blinks off and then on during the update. This blinking does not
occur when a 3278 display image is updated.
If the control unit detects a communication line problem or a program
error (when.a. is displayed in the Operator Information Area) while
updating your screen, the update operation is stopped and the screen is
restored to its original contents. If the error persists, successive retry
operations may be seen in this manner on the screen.
• The New Line (NL), End Message (EM), and Form Feed (FF) order codes
are displayed as 5,9, and ( respectively on 3275 and 3277 displays, but are
not displayed on the 3278.
• The Duplicate and Field Mark characters are displayed as an asterisk (*)
and semicolon (;), respectively, on 3275 and 3277 displays. The 3278
displays the Duplicate and Field Mark characters as an overscored
asterisk (
* )
and overscored semicolon ( -;), respectively, when the
A,aIA switch is set to A,a; when the A,aIA switch is set to A, only the
asterisk or semicolon is displayed .
• When a 3275 or 3277 Operator ID Card Reader operation is performed, the
cursor moves across the screen as the card is read.
When a 3278 Magnetic Slot Reader operation is performed, the cursor will
not move until the control unit processes all the card characters. When the
control unit is finished, and no error occurred, the cursor is moved to the
character position beyond the last character read in; if an error occurred,
the cursor is moved to the character position occupied by the last character
read in.
3278 Operator Information Area
The 3275 and 3277 System Available, Insert Mode, and Input Inhibited
indicators are not present on the 3278. Instead of these indicators the 3278
has an Operator Information Area in which symbols, words, and numerals are
used to display operating and status messages. The Operator Information
Area and the messages displayed in this area are described in Chapter 2.
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