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Technical Q&As: Device Drivers
Open Firmware is software that runs when the machine is initially powered on or restarted. Known as BIOS on other platforms, Open Firmware (Apple's implementation of the IEEE 1275-1994 standard) determines what hardware is in the machine, performs basic functionality testing, and initializes the hardware to a known state. Open Firmware also hands control of the machine to an operating system. Developers can take advantage of Open Firmware during their hardware bringup and testing. Developers can also provide FCode drivers to have their hardware participate in the boot process.
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Date
Disabling a Processor on a Multiprocessor System (HTML) ()
QA1141: Describes how to disable a processor on a multiprocessor system for testing purposes.
 2002-05-22
IODeviceTree & the IORegistry (HTML) ()
QA1120: Describes the IODeviceTree plane in the Mac OS X IORegistry.
 2002-02-13
What is an Open Firmware phandle, and why can't I access it from the Mac OS? (HTML)
HW76: Explains an "Open Firmware phandle" and why it is inaccessible from the Mac OS.
 1999-11-15
Are the Name Registry device tree nodes unique? (HTML)
Deprecated - HW64: Discusses whether Name Registry nodes copied from the Open Firmware device tree are unique.
 1999-10-11
Can you explain the words "begin" and "again"? (HTML)
HW70: Explains the Forth looping words "begin" and "again" and how to escape such a loop.
 1999-10-11
Using "words" in Open Firmware (HTML)
HW73: Explains how to search for specific entries within all the global and local Open Firmware words.
 1999-10-11
What is the return stack in Open Firmware and can I use it? (HTML)
HW67: Describes the purpose of the Open Firmware return stack and how developers can use it.
 1999-10-11
The AAPL, slot-name property and PCI (HTML) ()
HW61: Discusses the use of the AAPL,slot name property for PCI
 1999-04-19
Converting a numeric string to a number under Forth (HTML) ()
HW52: Demonstrates numeric string conversion in Forth.
 1999-03-29
What is a tokenizer? (HTML) ()
HW58: Defines a tokenizer.
 1999-03-29
Changing the configuration variable in Open Firmware (HTML) ()
HW40: Tells how to change the configuration variable in Open Firmware.
 1999-02-15
Difference between an Open Firmware word and method (HTML) ()
HW46: Describes the differences between an Open Firmware word and an Open Firmware method.
 1999-02-15
Switching between one and two machine mode for the Open Firmware user interface (HTML) ()
HW37: Explains how to change from one machine mode to two in the Open Firmware user interface.
 1999-02-15
What are generic names in Open Firmware? (HTML) ()
HW34: Documents the generic names in Open Firmware.
 1999-02-15