Squished_Squirrel
9th March 2006, 11:27 PM
Of course I haven't researched all the technical details on what I am about to say, so it may be mostly garbage... or might be close to the eventual solution.
First, create 3 partitions on the drive.
On the 1st partition, format 45% of it as FAT32.
On the 2nd partition, format 45% of it as HFS Extended, name it "Macintosh HD" and install your normal Mac OSX and software.
On the 3rd partition, format 10% of it as HFS Extended, name it "Windows XP" and install a stripped down OSX, similar to what is used for Utility disks.
On the 3rd partition, replace the OSX kernel (or any one of the programs that executes early as root/supervisor) with a program that loads into memory a standard PC BIOS from a PC that has the most similar hardware config. (One that understands the new partition scheme?) This, of course is the hardest part since it requires knowledge of assembly. It may be necessary to take advantage of CPU specific features to remap memory and make the BIOS appear in the proper place. Probably the same would be required for the video card BIOS since what I have read indicates that the existing video BIOS may not support INT 10. Some tinkering may be necessary to emulate CMOS for the replacement BIOS.
Now, cross your fingers and jump into the BIOS and let it re-init the machine as a standard PC... and hope that it doesn't blow away any custom CPU register changes made to get the BIOS into the right spot. If all works right, it should attempt to boot from the CD drive, and allow reading of a standard XP install CD.
All theoretical, and I am fully aware the BIOS loader would take someone who knows a pitshile about PC hardware and the core duo CPU.
The nifty thing is that no boot selector is required. Hold the option key down on boot, and select the drive called "Windows XP" and the computer will fire up the OSX partition that has the BIOS loader on it. It in turn will load the BIOS and boot from the first partition on the drive. The Mac will always remember the last partition you booted from too, so until the next time you hold option key down on boot, it will continue to start up in the OS you selected last.
It may even be possible to convert the FAT partition to NTFS after XP has been installed, since it is BIOS that looks at it, not EFI.
First, create 3 partitions on the drive.
On the 1st partition, format 45% of it as FAT32.
On the 2nd partition, format 45% of it as HFS Extended, name it "Macintosh HD" and install your normal Mac OSX and software.
On the 3rd partition, format 10% of it as HFS Extended, name it "Windows XP" and install a stripped down OSX, similar to what is used for Utility disks.
On the 3rd partition, replace the OSX kernel (or any one of the programs that executes early as root/supervisor) with a program that loads into memory a standard PC BIOS from a PC that has the most similar hardware config. (One that understands the new partition scheme?) This, of course is the hardest part since it requires knowledge of assembly. It may be necessary to take advantage of CPU specific features to remap memory and make the BIOS appear in the proper place. Probably the same would be required for the video card BIOS since what I have read indicates that the existing video BIOS may not support INT 10. Some tinkering may be necessary to emulate CMOS for the replacement BIOS.
Now, cross your fingers and jump into the BIOS and let it re-init the machine as a standard PC... and hope that it doesn't blow away any custom CPU register changes made to get the BIOS into the right spot. If all works right, it should attempt to boot from the CD drive, and allow reading of a standard XP install CD.
All theoretical, and I am fully aware the BIOS loader would take someone who knows a pitshile about PC hardware and the core duo CPU.
The nifty thing is that no boot selector is required. Hold the option key down on boot, and select the drive called "Windows XP" and the computer will fire up the OSX partition that has the BIOS loader on it. It in turn will load the BIOS and boot from the first partition on the drive. The Mac will always remember the last partition you booted from too, so until the next time you hold option key down on boot, it will continue to start up in the OS you selected last.
It may even be possible to convert the FAT partition to NTFS after XP has been installed, since it is BIOS that looks at it, not EFI.