Asynchronous Terminals and Printer Processes Programming Manual

TERMINAL PROGRAMMING CONSIDERATIONS
Page Mode
The terminal transmits the screen from the home position to
the previous cursor position. The WRITEREAD completes with
the screen data and field-separator and line-separator control
characters in BUFFER. COUNT^READ contains a count of the
characters returned by the terminal.
! set conversational mode
CALL SETMODE ( TERM^NUM, CHANGE^MODE, CONV^MODE );
IF < THEN ... ; ! error
.
! put the terminal into conversational mode
SCONTROL^BUF ':=' [ ESC, TCONV^MODE ];
! switch terminal back to conversational mode
CALL WRITE ( TERM^NUM, CONTROL^BUF, 2 );
IF < THEN ... ; ! error
Interrupt Characters
All four page mode interrupt characters are initially set to
the current page termination character. The initial interrupt
characters apply to a terminal when first opened if it is
configured as a page mode terminal. The interrupt characters
are restored to the initial values when the terminal changes from
conversational mode to page mode.
Page Termination Character. A page termination character (such
as <CR>, <ETX>, or <EOT>) is defined by the PAGETERM SYSGEN
modifier for each page mode terminal. Characteristics of the
page termination character are as follows:
• It is not counted in the count-read parameter returned from
the READ or WRITE procedures.
• It is transferred into the application buffer if an odd number
of bytes is read.
• The transmission is terminated automatically when the number
of characters specified in the read-count parameter is input.
• The file system does not issue <CR><LF> after receiving the
page termination character.
For ATP6100 subdevices, you can redefine the configured page
termination character by including the PAGECHAR attribute in a
CMI ALTER SU command.
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