GTCO Super L III - Users Guide - Manual (Page 40)

Super L III 40
There are two kinds of flow control:
 Software flow control is often used over communication links where only a 3-wire
cable is used (Transmit Data, Receive Data, Ground), or over telephone lines. The
sending device (such as Super L III) will immediately stop sending data when it
receives an ASCII XOFF character (CTRL-S, hex 13). Transmission will resume when it
receives an ASCII XON character (CTRL-Q, hex 11). Character flow control will work
with the straight through cable and the null modem cable above.
 Hardware flow control is not commonly used with digitizers and is therefore not
supported by the Super L III Controller. Contact our Technical Support Department
if you have hardware flow requirements.
Flow control may not be needed when a terminal or digitizer is directly connected to a
single-user computer. Most digitizing application software does not use flow control of
either kind.
Remote Commands
NOTE: The following information is not required for normal Super L III operation.
Super L III can receive commands from other devices through its RS-232C port. Commands
cause the Super L III to change the way it operates, to use certain coordinate formats and
to do other things directed by you or by an application program.
Commands offer another way to control Super L III operation besides the Tablet
Configuration Utilities. Certain Super L III functions can be carried out only through
commands.
If you are developing your own application software, be cautious about using commands in
your program. An interruption in power to the Super L III or a Reset will cause it to discard
any command changes it has received. This could leave the program confused about what
the Super L III is doing. A full system reset would then be needed to get the digitizer and
computer coordinated again.