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Note:
Data cannot be entered from the 2265 keyboard
once the 2845 recognizes a command from the central
processor. (An exception is the Write Printer command,
which has no effect on keyboard entry.) If a keyboard
key (other than the TEST key)
is
depressed at any
time after command processing is begun, the keyboard
locks and no character is entered into the system. This
ensures that command operation will proceed without
interference from the 2265 keyboard.
Even if no key is depressed until after the command
operation
is
successfully terminated, the keyboard will
still lock when a keyboard key is depressed and no charac-
ter will be entered if the central processor sends an EaT
or SOH character to end the operation. Locking of the
keyboard thus calls attention to the operator that an
operation has transpired and that the display screen should
be scanned for a computer message and appropriate action
taken. The RESET key must be depressed before data may
be entered from the keyboard.
If, however, the STX/EOT response
is
sent by the
central processor to end the command operation, the
keyboard is automatically restored and data may be keyed
in immediately without depressing the RESET key. This
latter method may be used when the central processor
and the Display Control are operating in conversation mode.
Use of New Line (NL) Symbol
The NL symbol prohibits the transfer of data displayed
between the NL symbol and the end of the display line
containing the symbol during Specific Poll and General
Poll operations. This capability has many applications,
one of which is to display both fixed and variable data
when only the variable data is to be transferred to the
central processor. The ultimate benefit is a saving
in transmission time. For example, fIXed information
such as the words "name", "address", and "date" may
be entered and displayed on the right side of the 2265
Display Station screen. Variable Information, actual
name, etc., is then keyboard-entered on the appropriate
line to the left of the fIXed information. Following the
entry of the last character in each display line of variable
information, the NEW LINE key is depressed. This
causes the NL symbol to appear between the variable and
the fIXed information and also positions the cursor in the
first display position of the next line. Figure 3 illustrates
a display at the completion of data entry from the key-
board.
After all the data has been entered in the display buffer
and is displayed on the screen, the ENTER key is depressed.
Receipt of a poll command causes a transfer to the I/O
channel of all data between the SaM and the cursor (except
the data displayed between the NL symbol and the end of
the display line containing the symbol). In the display
22
shown iIi Figure 3, all the data except the fIXed informa-
tion (name, address, date,part no. and quantity) would
be transferred to the I/O channel. The NL symbols would
be included in the data transfer. However, if more than
one NL symbol is displayed on a display line, only the
first NL symbol is transferred.
Correction of Errors from 2265 Keyboard
Typographical errors are correCted easily by the BKSP
I
(backspace), SPACE/ERASE-ADVANCE, and START
keys. To speed correction, the first two named keys also
provide a rapid cursor-positioning facility. That is, when
depressed to its final stop, the key's operation is repeated
at about nine characters per second as long as the key is
held depressed. These keys are also described in Tables 1
and 2.
2265-to-Printer Operation
When the Printer Adapter Feature is installed, the 2265
keyboard PRINT key causes the following (see also Tables
1 and 2):
1. All the keyboard keys are locked (except the ERASE,
RESET, and TEST keys).
2. An EOM symbol is displayed on the screen in the posi-
tion occupied by the cursor.
3.
Da~a
displayed on the 2265 from the first displayable
position to and including the BaM symbol is transferred
to the printer. All characters are printed (except NL
symbols and data between an NL symbol and the end
of the display line containing that symbol). The EOM
symbol is printed to indicate the end of a message.
If NL symbols are displayed, only the first NL symbol
on each display line is transferred to the printer buffer;
NL causes a carriage return-line feed operation but no
symbol is printed.
4. At the completion of the print operation, the 2265 key-
board is restored.
If a parity error is detected in the display buffer, charac-
ters with parity error are printed as they are read out of
the buffer and a Check symbol ( , ) is printed as· the last
character (following the EOM symbol).
If the 1053 Printer is busy at the time the PRINT key
is depressed, the
~eyboard
PRINT key operation is queued
and is executed when the
1053
Printer becomes available.
If desired, the operator may cancel the PRINT key opera-
tion and restore
tIle
k~ybo,ardby
depressing the RESET
key.
D~r~~;J~~;~;4:26>to
.. Printer operation is be-
ing·executed,·the~5?keyboard is inoperative.
The format of
the
PrltJ,ter copy is controlled by the NL
characters in the transferred data. Since NL symbols cause
a carriage
return/1in~feed
at the Printer, they should be
used to achieve sP3:cing When desired. All other characters
are printed exactly as they appear on the 2265 screen.
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