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Unsupported eMac - any way to get OS 9 to show in OS X startup disk selector?

3lectr1cPPC

Well-known member
Today I wiped my eMac clean and dual-booted Mac OS 9 and Sorbet Leopard on it. It’s a 1.0GHz model, but it’s the SuperDrive variant that doesn’t officially support OS 9 booting. The macos9lives patched CD took care of that pretty quick, but because it’s unsupported, the OS 9 partition doesn’t show up in the OS X Startup Disk preference pane. I can select the OS 9 drive from the bootpicker, but this takes a lot longer due to having to wait for it to finish searching the bus for bootable volumes. Is there any way to force the OS X preference pane to show the OS 9 volume, or am I stuck doing it this way? OS 9‘s control panel has no issue selecting the OS X volume.

Thanks!
 

bloedmage

New member
Run the following script in the terminal, it should enable OS9 in the Startup Disk PrefPane in OS X.

#!/bin/sh
echo Enabling OS 9 booting...
echo "You may have to enter your password"
# Use nvram command to setup nvramrc with script to make open firmware changes
sudo nvram nvramrc='" /" select-dev
" PowerMac4,4" encode-string " model" property
" PowerMac4,4" encode-string " MacRISC" encode-string encode+ " MacRISC2" encode-string encode+ " MacRISC3" encode-string encode+ " Power Macintosh" encode-string encode+ " compatible" property
unselect
'
# Enable use of nvramrc on boot. Change to "false" if you want to disable again. Or just clear/reset nvram.
sudo nvram "use-nvramrc?"=true
echo done.
 

Chopsticks

Well-known member
I used to use a tool called LeopardAssist that allowed you to do this using a GUI (works in tiger too), but I might save this script for future use.
fwiw the OS X startup control panel appears to check for what version of MacRISC support is listed in open firmware. Enabling these options in nvram basically just tells OS X the cpu supports OS9 booting thus showing up in the startup disk preference pane.
in case anyone is wondering how the Ross v9 CD boots up without messing around with open firmware, they basicuslly hacked the macOS rom file to add in the missing support feature/requirements. In fact interestingly it will even boot off a hdd with no macOS 9 disk driver partition as they baked that in too.
 

Thorhall

New member
What I did is write a shell script using the bless command. You need to set the OS9 drive as the bootable disk in startup disk preferences if it also contains an OS X install, then run the shell script to bless os 9 and finally reboot from the Apple menu and it will launch straight in to os 9.
 

Chopsticks

Well-known member
just re-read the OP and in regards to it taking ages to finishing scanning when you use the open firmware boot picker its because the boot picker also searcher for Netboot devices and will do so regardless if you are connected to a lan or not. my understanding its it its listening for the available service and had a long timeout before giving up. so while using the script to enable os 9 in the OS X boot picker id also recommend booting into Open Firmware and running the following command:

setenv skip-netboot? true

this will disable it searching for network boot shares and just check the typical IDE/SCSI/Firewire bus's, doing this will let you select a drive in the boot quicker in a couple seconds rather then 20-30 seconds. I still 100% recommend running that script posted by @bloedmage but at least for me I've found it handy speeding up the boot picker as both my fall back method and also because I use it often to select other boot media during my system hacking projects
 
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