[rescue] Odd Mac startup problem

[Micah R L]

William G. Gruesbeck wrote:

>>> Does a 7300 *have* OpenFirmware?
>>>
>>> Command-Option-O-F at boot, right?
>>>   
>>
> Yes to both questions. And onthe old world macs the OpenFirmware 
> defaults to the serial port, there are two variables that you can set 
> to put output to the display and keyboard. However, for the life of me 
> I can't remember what they are. I had to set them a long time ago so I 
> could see what I was doing easily since I had a a crap serial cable. 
> Google should help here, especially if you search for linux as well 
> since I think there was either a slackintosh or yellow dog faw out 
> there that had all that information.

If you have linux installed on the machine, you can use the following 
commands:
nvsetenv input-device kbd
nvsetenv output-device /chaos/control

I think you can use the 'nvram' command from within OS X.
 From OS9, you can use the program bootvars, available here:
http://www2.tw.netbsd.org/NetBSD/arch/macppc/macos-utils/bootvars/