Transmitting From The Keyboard; Receiving - IBM 5100 Communications Manual

4
When data is entered in the extended display and the extended display becomes full,
the oldest line is deleted when a new line is entered.
Data in the extended display can be thought of as a page of data lines. A line
contains the data between new-line and/or line feed function characters. A message
contains the data between the start of transmission and end of transmission function
characters and contains one or more lines. These function characters are transmitted
by the 5100 and the remote system to control the length and spacing of the lines.
Normally, the first 64 characters of the 14 most recent lines of the extended display
are displayed on the screen; however, by using the scroll keys, you can move any
part of the extended display to the screen.
TRANSMITTING FROM THE KEYBOARD
When the 5100 is online with a remote system, each character you enter from the
keyboard is displayed on the screen and transmitted to the remote system. When
you enter a line longer than 64 characters, each additional character entered is
displayed in position 64 and all data on the display screen moves one position to
the left. Pressing EXECUTE indicates the end of the line and moves the data on the
display screen up one line and to the right so the first character of each line is in
position 1 on the display screen.
RECEIVING
If the 5100 is receiving data, each character is displayed on the screen as it is
received. A line containing 64 characters or less is displayed exactly as it is
received. Lines longer than 64 characters are formatted into 64-character lines on
the display screen as they are received. When the end of transmission character is
received, the format of the longer lines changes and only the first 64 characters of
each line are displayed. The part of the lines not displayed is stored in the extended
display and can be moved to the screen by using the scroll keys.