# PxPlus System Programs and Files

*TTY | Load Keyboard Definitions

The *TTY program is used by most terminal device drivers to load the keyboard control sequences for the terminal. It uses the tables defined by "*UCK" to configure the device, which is identified by the system variable LFO (Last File Opened).

Whenever a terminal device driver is executed, it should transfer control to this program to load the CTL definitions from the *KYBRD.CFG or *KYBRD.STD files.

For more information on the *KYBRD.CFG and *KYBRD.STD files, see Keyboard Definition Files.