Asynchronous Terminals and Printer Processes Programming Manual

TERMINAL I/O
Break Characteristics
SETMODE 11 enables and disables the BREAK key. For TERMPROCESS
devices, use the NOBREAKMON SYSGEN modifier to disable break
checking. For ATP6100 subdevices, you can enable and disable
break checking by including the BRKENABLE attribute in a CMI
ALTER SU command.
When the terminal operator presses the BREAK key, the process
that enabled break receives a system message. The BREAKCOUNT
SYSGEN modifier causes the transfer count to be included in the
message. BREAKCOUNT can be turned on and off with the CMI ALTER
SU BRKCOUNT command.
The ECHOBREAK SYSGEN modifier is for 6520 and 6530 terminals that
are supported by ATP6100. When the operator presses BREAK, the
terminal sends the break signal to the controller continuously
until it is disabled. ECHOBREAK causes the break signal to be
returned to the terminal to turn off the break condition.
SETMODE 12 has two parameters. Parameter 1 determines the file
access type, either normal or break. Parameter 2 determines the
terminal access type, either normal or break. When parameter 2
is set to 1, only operations that are associated with break are
allowed.
Control Characters
ATP6100 and TERMPROCESS use several ASCII control characters.
You can change their values at SYSGEN time. For ATP6100
subdevices, you can change some values with CMI. Table 2-3 shows
the control character default values and how to change them.
Table 2-3. Control Characters
Control Default SYSGEN CMI
Character Value Modifier Attribute
_______________________________________________________________
Backspace (<BS>) %010 CTRL/H DEFBS (none)
Line feed (<LF>) %012 CTRL/J DEFLF DEFLF
Vertical tab (<VT>) %013 CTRL/K DEFVT (none)
Form feed (<FF>) %014 CTRL/L DEFFF (none)
Carriage return (<CR>) %015 CTRL/M DEFCR DEFCR
Cancel (<CAN>) %030 CTRL/X DEFCAN (none)
End of file (<EOF>) %031 CTRL/Y DEFEOF (none)
November 1987 2-5