TITLE
    PowerBook: Open Firmware And Exiting To Mac OS
Article ID:
Created:
Modified:
24605
9/11/98
11/7/00

TOPIC

    I have powered up my PowerBook computer and now there is a white screen stating:

    Open Firmware, X.XX
    To continue booting the Mac OS type:
    BYE<return>
    To continue booting from the default boot device type:
    BOOT<return>
    ok
    0)


    - What is this screen?
    - How did I get to this screen?
    - How can I get back to the regular Mac OS?
    - Which PowerBooks use this?


DISCUSSION

    This screen is the Open Firmware screen. Beginning wih Power Macintosh computers equipped with PCI slots, Apple has used a firmware operating systems called Open Firmware for controlling hardware.

    Open Firmware is a cross-platform firmware standard for controlling hardware and is used by all PCI-based Mac OS computers. Open Firmware is used mainly by Apple hardware developers and rarely is there a need to start up into Open Firmware.

    While it is difficult to start up into Open Firmware, if does happen if you hold down the 'Command-Option-O-F' keys from a cold start while the chime is being played. The PowerBook should never start up into Open Firmware on its own.

    If you are at the Open Firmware screen and want to go back into Mac OS, type "BYE" without the quotes at the command prompt, then press the return key. This exits Open Firmware and continues starting up into Mac OS.

    Only PCI-based PowerBooks will start up into Open Firmware. These started with the PowerBook 2400, 3400, and G3/G3 series computers. Previous PowerBook models will not start up into Open Firmware.

Document Information
Product Area: Computers
Category: PowerBook
Sub Category: General Topics

Copyright © 2000 Apple Computer, Inc. All rights reserved.