Technical Notes: Device Drivers
Open Firmware
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. |