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Question about end of boot loader.
Posted: Sat Nov 10, 2007 2:03 pm
by crazygray
If the end of end of the bootloader ends with 0xAA55 in the actual binary does it go 0x55 0xAA because of the intel proccesor?
Posted: Sat Nov 10, 2007 2:34 pm
by inflater
No. That means the BIOS boot signature, if BIOS will find this sig, it will load from the boot sector. Some BIOSes are ignoring this sig.
Regards
inflater
Posted: Sat Nov 10, 2007 2:41 pm
by XCHG
Intel processors (most of them) are little-endian. This means that the least significant byte of a value is stored in the lowest address of memory. In the boot loader, we will have the 510th (zero based) byte as 0x55 and the next byte as 0xAA so as a little-endian WORD value (16-bits), this can be represented as 0xAA55. Note that the least significant byte is the rightmost byte or the 0x55 which in here, since it is the first byte, is stored in the least significant byte and the most significant byte (0xAA) is stored as the leftmost byte. When you look at your boot loader's contents in a hex editor (perhaps), 0x55 should come first, followed by 0xAA.
I hope that helps. Good luck.
Posted: Sat Nov 10, 2007 2:44 pm
by crazygray
