Asynchronous Terminals and Printer Processes Programming Manual

TERMINAL PROGRAMMING CONSIDERATIONS
Conversational Mode
form feed (%014) or vertical tabulation (%013) character through
the WRITE procedure. However you must include a delay in the
program to give the form movement enough time to finish:
DEFINE TWO^SECONDS = 200D#;
INT FORM^FEED := %014 '<' 8;
.
.
CALL WRITE ( HOME^TERM^NUM, FORM^FEED, 1, NUM^WRITTEN );
CALL DELAY ( TWO^SECONDS );
The application process is suspended for two seconds after the
form feed character is issued to the terminal.
Interrupt Characters
The default interrupt characters apply to a terminal when it is
first opened. They are restored to the initial values when the
terminal changes from page to conversational mode. The default
interrupt characters are as follows:
• Line termination (CTRL/M, %015)
• Backspace (CTRL/H, %010)
• Line cancel (CTRL/X, %030)
• End of file (CTRL/Y, %031)
Line Termination Character. The line termination character, when
received from a terminal, signals that the current line transfer
is complete.
The line termination character has the following characteristics:
• It is not counted in the count-read parameter returned from
the READ or WRITEREAD procedures.
• It is transferred into the application buffer if an odd number
of bytes is read.
• If carriage return is the current line termination character,
another parameter determines whether or not the file system
automatically issues a line feed after receiving the carriage
return. Typically, the line feed is issued if the terminal
does not provide its own line feed.
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