A lot of people these days appear to be under the impression that Macs have a BIOS, which is unfortunate because they actually have something much better - Macs have OpenFirmware. This is true for G4 Mac Minis, PowerBooks, iBooks, iMacs, eMacs, and Dual G5s… I could go on and on.
I got most of this info from experience and the Apple Developper Connection - if you’re not a member yet, sign up, it’s free.
You can get into OpenFirmware using this key sequence:
CMD-OPT-O-F
In detail, this means using two hands, holding “command”, “option” and “f” on the left and “o” with your right hand. Do this while booting your computer and you well hear two chimes. At the end of the chimes you will be greeted with an
On my G4 Mac Mini, for example, I can hold down the power button for roughly 10 seconds and I will hear the chimes - this should work for iMacs as well.
The OpenFirmware prompt that looks like this:
ok
0>
Congratulations, you’ve accessed your “BIOS” you switcher!
Now that we’ve passed this glorious milestone, we have some work to do. After all you came here for a reason right? (and not just to click on the ads, wink-wink nudge-nudge)
Some useful commands that save me time and time again, and enable reparation of the G4 Mac Mini:
Boot your Apple computer using the default boot device:
0 > mac-boot
Boot your Mac using the inserted CDROM at the yaboot directory for linux CDs:
0 > boot cd:,\install\yaboot
To eject a CDROM from your Mac:
0 > eject cd
If you have any other OpenFirmware tips to share, feel free to comment!
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September 21st, 2006 at 9:40 am
Pingback from blandname · Access Your Computer’s BIOS
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July 24th, 2007 at 9:53 am
Tim de Vries
have you tried it yet, techman?
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July 24th, 2007 at 9:54 am
Tim de Vries
have you tried it yet, techman? If it’s an apple, and with how they’ve been fairly consistent over the years, I would guess so. It does with an iMac.
July 25th, 2007 at 5:40 pm
blandname
Actually, guys, the new Macs use EFI, and there is no built-in shell access to it yet.
On the other hand, if you are interested in getting your feet wet with EFI on an Intel Apple Mac, you may want to checkout rEFIt which is like BootCamp, only supports other operating systems as well.
Otherwise, holding the eject key on the keyboard will work, so will holding the mouse button down during boot up. I have yet to get a disc stuck in newer Macs and not have either of these work - aside from the occasional drive failure.
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November 24th, 2007 at 9:10 am
Tahir
I was trying to install Leopard to my MacMini and things got funny. Now I could not get it started. Press the power button, it starts, sound and then truning wheel…and then it stops. I had my Tiger cd inside and couldn’t get out, the keyboard eject didn’t help, etc.
Try and error I found above as well (accessing BIOS and ejecting). However, I still could not get it going?
Question;
- how do you create a “start up” cd in Mac? ıs there such a thing?
- what else could you suggest?
Many thanks.
November 24th, 2007 at 9:32 am
blandname
Are you using a newer Intel-based Mac Mini by chance?
In this case, try holding down the option key on your keyboard if it’s a Mac keyboard, otherwise, try the F12 key on your PC keyboard.
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November 24th, 2007 at 9:39 am
Tahir
I have two MacMinis home. Install of Leopard worked just fine on Intel with no problems. It is the powerpc one that got stuck like this.
My problem in fact is now not getting cd out but somehow making MacMini start (boot).
Above you have a comment about booting for Linux. How about for mac, t force it to cd boot?
Believe “mac-boot” would take me to original setting which is hard drive and that somehow does not work.
November 24th, 2007 at 10:32 am
blandname
OK it sounds like can at least get into open firmware - try typing
boot cdDoes that work?
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January 20th, 2008 at 11:00 pm
zaid
where is command button on keyboard
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April 19th, 2008 at 12:21 pm
nazmul alam
hi, i hve apple laptop macbook frm my friend(u.k).he gift me this macbook laptop without any dvds or cds.nw its start bt nt operating system windows vista start.
Apple MacBook
Model no: A1181
after start show me messages
windows failed to start. A recent hardware or software change might be the cause. To fix the problem:
1.Insert your windows installation disc and restart your computer.
2.choose your language setting, and then click “Next.”
3.Click “Repair your computer.”
If you do not have this disc, contact your system administrator or computer manufacturer for assistance.
File: NETIO.SYS
Status: 0xc0000098
info: windows failed to load because a required file is missing,or corrupt.
Plz help me how can i do start operating system windows vista.i cnt speak enough english. plz send me solutions in my email address.please…..help meeeeeeeeeeeeeeeeeeeeeeeeeee……………………….
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July 2nd, 2008 at 8:25 am
Anonymous
command button is the one with the apple symbol on it.
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July 30th, 2008 at 6:48 am
Bob
can I remove macs operating sistem on a mac and install xp pro
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August 1st, 2008 at 3:58 am
Cam
Sounds cool your Macs. I started from Dos on a 286 and taught myself
up through to vista 64, putting together hundreds of mainboards, video cards, Cpu’s, memory, bios upgrades and drive combinations.
Eventually settling on xp pro fine tuned like a stradaverus, rock solid no leaks
back to redmond.
What I’m getting at those who have not been down this path, and are using
a playstation counterpart of a PC, have missed the thrill and satisfaction of
the challenge of a complicated elecronic modular puzzle that is a PC,
and that because it is so versatile, in the right hands can take you further
into unknown realms, if you know how.
Still respect your Macs. To me Mac’s are clostraphobic, only my opinion.