iMac G3 developer problem?

Your iMac is booting into Open Firmware. Try the following sequence: After you type each line, press <Return>:

reset-nvram

set-defaults

reset-all

Out of curiosity, which BootROM version does your iMac 333 have? The final group of 333 MHz models shipped with a ROM code that caused problems with the OS X installation. You can read about it in this 7½ year-old Forum Topic.

If the iMac doesn't keep the correct date & time after being unplugged from electricity, I'd replace the internal 3.6-volt, ½AA lithium battery. A new battery often eliminates startup issues, because the settings stored in the PRAM (such as the startup disk) can get corrupted with a very weak or dead one. Your iMac should have and may already have had the iMac Firmware Update 1.2 run, prior to installing OS X. Unfortunately, the firmware update must be run when the computer is booted from its internal hard drive, running a version of OS 8 (8.1, 8.5, or 8.5.1), so hopefully it was already done.

Go into preferences for the startup disk. Try changing the bootup OS. Set it back to what it was. Prehaps, the setting got confused.

Robert

I think the partition to boot is getting lost in the open firmware. I do not know how or why. You can check on this.

On of the variables contains what to boot.

List of variables:

printenv

Sometimes if volumes don't appear in Startup Manager (what you get when you hold down the Option key at startup), you need to reset the Mac's PRAM, NVRAM, and Open Firmware. Shut down the Mac, then power it up, and before the screen lights up, quickly hold down the Command, Option, P, and R keys, until the Mac has chimed twice more after the powerup chime.

Then, before the screen lights up, hold down Command-Option-O-F until the Open Firmware screen appears. Then enter these lines, pressing Return after each one:

reset-nvram

set-defaults

reset-all

"The reset-all command should restart your Mac. If so, you have successfully reset the Open Firmware settings."

http://support.apple.com/kb/TS1812?viewlocale=en_US

Should the fail...

Try taking the battery out for 10 minutes. Put battery back in. Cross fingers. Power the machine back on.

How to eject a cd from the internal cd drive:

eject cd

List of devices:

devalias

List of variables:

printenv

More than you ever wanted to know about open firmware

http://www.firmworks.com/QuickRef.html