Phipli
Well-known member
Evening folks.
Apple released the early G4s, Yikes and Sawtooth, with special, updated versions of Mac OS 8.6. I'm not sure if people are aware, but @LightBulbFun did some excellent work here to produce a modified version of the Mac OS ROM file, that goes in the System Folder, to enable this special version of 8.6 to be booted on unsupported machines including the Pismo, Gigabit Ethernet G4, some DA G4s, some extra iMacs that are not usually supported, some iBooks, probably the Cube and perhaps some early PowerBook G4s? The requirements are that the machine needs to have an old enough processor and be similar to an officially supported machine. Machines with the G4 7450 processor and newer are not immediately supported without some further fiddling in OpenFirmware.
I decided to take this modified ROM file and wrap it up in a modified version of the Mac OS 8.6 installer CD. I'm not going to lie, while most of it was easy, getting the Installer application on the CD to actually install the modified file was way more tricky than I expected. Yes I tried replacing the file in the two tomes it appeared in. That lost me about 5 hours of my day. Yes I tried editing the install scripts, it wasn't possible to convert them between their compiled state and editible state easily, given my poor knowledge of the Apple Installer SDK. Right. Anyway.
Make sure your computer is running the most up to date firmware. I forgot to and it caused me issues on my GigE G4.
Features of my CD image :
Things I did :
My hosting service isn't great sorry. People in the Americas might find the connection drops. All I can say is sorry, but if you keep trying it eventually should complete. The download is about 400MB.
Consider the software to be experimental. It might not work, but if it does
Please don't ask for changes, they're likely impossible and I've had a really crap day.
Apple released the early G4s, Yikes and Sawtooth, with special, updated versions of Mac OS 8.6. I'm not sure if people are aware, but @LightBulbFun did some excellent work here to produce a modified version of the Mac OS ROM file, that goes in the System Folder, to enable this special version of 8.6 to be booted on unsupported machines including the Pismo, Gigabit Ethernet G4, some DA G4s, some extra iMacs that are not usually supported, some iBooks, probably the Cube and perhaps some early PowerBook G4s? The requirements are that the machine needs to have an old enough processor and be similar to an officially supported machine. Machines with the G4 7450 processor and newer are not immediately supported without some further fiddling in OpenFirmware.
I decided to take this modified ROM file and wrap it up in a modified version of the Mac OS 8.6 installer CD. I'm not going to lie, while most of it was easy, getting the Installer application on the CD to actually install the modified file was way more tricky than I expected. Yes I tried replacing the file in the two tomes it appeared in. That lost me about 5 hours of my day. Yes I tried editing the install scripts, it wasn't possible to convert them between their compiled state and editible state easily, given my poor knowledge of the Apple Installer SDK. Right. Anyway.
Make sure your computer is running the most up to date firmware. I forgot to and it caused me issues on my GigE G4.
Features of my CD image :
- This CD should boot most supported unsupported machines, by holding the 'C' key.
- The firmware updates you might need are included on the CD.
- An Apple made Machine ID spoofer Control Panel is included in utilities in case you need it.
- The installer works and provides a system with the modified Mac OS ROM file.
- The restore application works and restores an image including the modified Mac OS ROM file.
- For some reason, sometimes Pismos (perhaps other similar machines) power off when they start loading the desktop from a CD. Installed systems work just fine, but you might need to boot from another disk while you install.
Things I did :
- I modified the restore image to add the Mac OS ROM file.
- I modified the CD System Folder to add the Mac OS ROM file.
- I added the Machine ID control panel in Utilities (but not the System Folder, I probably should have).
- I removed the machine specific white-list from the installer program so it will launch on absolutely any machine, regardless of whether it is appropriate or not.
- I made a new installer script, and tagged it on the end of the 8.6 update in the Installer, so that it silently swaps in the modified Mac OS ROM file without bothering the user.
- I added a load of firmware updaters in a folder.
- I added some ReadMes for clarity.
- I messed up the order of the icons on the CD by accidentally clicking "Clean Up" when I didn't mean to.
My hosting service isn't great sorry. People in the Americas might find the connection drops. All I can say is sorry, but if you keep trying it eventually should complete. The download is about 400MB.
Consider the software to be experimental. It might not work, but if it does
Please don't ask for changes, they're likely impossible and I've had a really crap day.
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