Technical Q&A HW37

Switching between one and two machine mode for the Open Firmware user interface

Q: How do you change between one and two machine mode for the Open Firmware user interface?

A: The configuration variables input-device and output-device hold the devalias for the devices. On earlier PCI Macintoshes, the value for both of these variable is "ttya" for serial port A. "ttya" is the value for a two-machine user interface. On newer machines, the value for the output device is the devalias screen. The input-device can be "kbd" or "keyboard." Setting the input-device to "kbd" or keyboard will direct input from the keyboard, and setting the output-device to screen will direct the output to the target machine. Use devalias from the user interface to view the aliases for the screen and keyboard. For more information, see Tech Note 1061, "User Interface."