The Open Firmware Wiki

[Amethyst1]

So, I go into OF and look for set_dfs_hi to force my PowerBook G4 1ghz Titanium to stay running at full speed ?

The Titanium doesn't have a 7447 or 7448.

 

[Macbookprodude]

The Titanium doesn't have a 7447 or 7448.

Yea I know it doesn’t.

 

[adam25255]

Documentation from Apple.(search for “open firmware”)

Documentation Archive

 

[DistroHopper39B]

I have figured out a way to boot from USB on ANY PowerMac, as long as you have a USB hub. https://forums.macrumors.com/threads/booting-from-a-usb-drive-on-a-powerpc.2281823/post-30995740

 

[thenebular]

The first half of chapter 4 of Mac OS X Internals is a damn good resource

awesome-iOS-resource/Books/Mac Os X Internals - A Systems Approach.pdf at master · gopalkrishnareddy/awesome-iOS-resource

:iphone: A curated list of awesome iOS resources, including conferences, books, blogs, articles, websites and documentations - gopalkrishnareddy/awesome-iOS-resource

github.com

 

[barracuda156]

Found this to solve my problem on 10A190 with incompatible PCIe device that led to KP on boot: http://macos9lives.com/smforum/index.php?topic=3233.0

Code to disable a device for a given boot:

dev @device@
" reg" delete-property
" interrupts" delete-property
" none" encode-string " compatible" property
device-end

Where @device@ stands for specific device, in my case it was pci3.

 

[AphoticD]

Added dot point to Tricks section (in first post) re:spoofing machine model / ID

Thanks to @Amethyst1 post here:

https://forums.macrumors.com/threads/the-puma-thread-mac-os-x-10-1.2119073/page-3?post=30122693#post-30122693

 

[mortlocli]

Just wanted to say a THANK YOU for the info in this thread.

Fooling around with OSs and thought Id killed my G4 iBook:
couldn't boot, couldn't eject the CD, couldn't get to OF. No key combination would result in any change. Could turn it on..to nothing, then the power light would go off. Used the caps lock key to see if alive or not.

Then found I could power on via button, hold down to power off, power on and hold the button down, would peep and could hear the HD working, continue to hold down and the open was : 'shut-down or 'continue to boot' (cant remember exact wording) which would take me back to a seemingly dead (almost) iBook..or to boot up the previous OS...which I lacked understanding off.

But I could eject the CD and replace it with a Leopard one..but still no go.

Then found this thread..(which I was missing thru not asking the right question worded correctly basically) and:
o To reset the system NVRAM, enter reset-nvram

o To reset all changes made to Open Firmware, enter set-defaults

o To reset the machine, enter reset-all

..and yep - got back to Leopard booting...and now Sorbet installed.

Hurrah !!!
..so glad to have my iBook back!!!