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Downgrading New World Roms?

zarky

Active member
I need to downgrade the rom/firmware on my powerbook pismo, is there a way to do so?
 

zarky

Active member
Thank you, i need to roll back the firmware on my Pismo because the macos9lives 9.2.2 installer put the 10.2.1 firmware on it and now my firewire doesn't work. So I want to roll it back to 4.1.8, the last pismo firmware.
 

zarky

Active member
theres a chance i'm not understanding something, info seems hard to come by these days on your search engine of choice.

ROM revision: $77D-45F6
Boot ROM Version: $0004.18F5
Mac OS ROM file version: 10.2.1

Looks like my boot rom is already 4.1.8? And OS rom is 10.2.1... Is this even the source of my firewire issue? Im at a total loss at the moment.
 

greystash

Well-known member
theres a chance i'm not understanding something, info seems hard to come by these days on your search engine of choice.

ROM revision: $77D-45F6
Boot ROM Version: $0004.18F5
Mac OS ROM file version: 10.2.1

Looks like my boot rom is already 4.1.8? And OS rom is 10.2.1... Is this even the source of my firewire issue? Im at a total loss at the moment.
Yes that appears correct.
- "ROM revision" I believe is the revision of the boot firmware located on the Pismo's ROM chip.
- "Boot ROM Version" is the boot firmware version of the machine.
- "Mac OS ROM file version" is the version of the Mac OS ROM file located in the System Folder.

I don't think any of the pre-built Mac OS 9 Lives images come with any firmware installers/updaters.

I can't remember if the Mac OS 9 Lives installers have a modified Mac OS ROM file or not. But it may potentially be what you would want to look at changing if you've installed the OS from a Mac OS 9 Lives CD? If you reinstall the system with an original disc for the Pismo, or from a Mac OS 9 Universal installer this will install the correct Mac OS ROM file for your machine.

Unless you ran a firmware update it's unlikely you need to do anything with the Firmware.
 
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zarky

Active member
yeah thanks, guess i got caught up in a bit of a red herring and kind of misunderstood what was going on.
 
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