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Japan

macrumors newbie
Original poster
Hey everyone,

I have a quite banal question concerning the inside of a Mac and hope you can help me out. Although I am an experienced Mac user for many years myself I couldn't answer this question when asked. Is there a comparable device inside a Mac that acts as the BIOS in a PC? If not, what is the reason the Mac doesn't need one? (I have been told before that such a thing is not needed.)

Thanks for any answer that will help me not to embarass myself again 😛

Japan
 
The closest equivalent to the PC BIOS in Macs is Open Firmware. You can access it from a "New World" Mac by holding down Command+Option+O+F at startup. If it worked, you'll see an odd-looking command prompt like screen that doesn't look at all like Terminal. In here, you can make low-level hardware changes, such as resetting the NVRAM (reset-nvram), resetting everything (reset-all), continuing normal startup (mac-boot) or rebooting the Mac (reboot). The name in parentheses is the command you type at the Open Firmware prompt to achieve the described effect.
 
Open Firmware is much cooler than a BIOS!

It can be programmed to do some cool things like this.

Note that it mentions some of the cool things you can do in OF. A machine booted into OF can be telneted into for example (try that with a PC BIOS)!

Edit to add : Intro to Open Firmware

This is even cooler. Skip to part II
 
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