A few other notes about OF. First, in the unfortunate event of your Mac
becoming unbootable, you can use the catch-all fix of zapping the PRAM
. Hold down command-option-shift-p as you reset the machine. This will zap all the settings to their factory default
, meaning you should at least be able to boot MacOS
, if nothing else.
Secondly, all PCI based Macs have Open Firmware, but it's a little harder to access on OldWorld Macs. It's not impossible, however. These machines defaulted to serial terminal I/O for Open Firmware (which is pretty dumb, considering pretty much every Mac ever made has had a monitor and keyboard attached to it). You need a program called BootVariables (which is becoming annoyingly hard to find...but, you can, as of this writing, downlaod it from http://wuarchive.wustl.edu/systems/unix/NetBSD/arch/macppc/macos-utils/bootvars/bootvars1.3b.sit.hqx), which will let you change the the NVRAM settings within MacOS. Open the program, and, if you're on a OldWorld Mac, note the input-device and output-device fields are both set to "ttya", which is the printer serial port. You can change the input device to "kbd" to get it to accept input from the keyboard. Unfortunately, the output-device is a little more complicated. Under MacOS 8.x or higher, open the Apple System Profiler and click the "Devices and Volumnes" tab. Undepress the "Display card" arrow and note the "Card name". On my old my UMAX clone with a Rage 128 Orion PCI card, this was "ATY,Rage128o". Clones with an IMS card will look more like "IMS,tt128mb", There will always be a comma in the name, though.
Now, enter in the output-device "/bandit/ATY,Rage128o", or whatever your card is. Note that it's only /bandit for the Bandit PCI bus on newer Macs. Early first-generation OF Macs had onboard video, in which case the output-device is simply "/chaos/control". Once you've got that all set, click "Write&reboot" in BootVariables and hold down the command-option-o-f hotkey. If you're lucky, you should now the see the white Open Firmware screen on your monitor. Note that the NVRAM seems to reset when you power the machine off, so you'll need to reenter the devices each time you want to go into OF. Good luck.