Magic Lantern Firmware Wiki

Previous work by Trammel:

The bootrom (at 0xffff0000) allows the loading and execution of code if:

  1. the bootdisk flag is enabled in camera (required on 400D, 500D, 550D, 600D, 1100D, 50D, 60D, 7D, at least)
  2. the boot sector contains the strings "EOS_DEVELOP" and "BOOTDISK" at the right places, depending on 3 FAT versions.

Based on bootloader 0.13, these offsets (hexa/decimal) are:

FAT version Volume Label = "EOS_DEVELOP" Bootcode+2 = "BOOTDISK" comments
FAT12/16 0x2b/43 0x40/64 works
FAT32 0x47/71 0x5c/92 works
ExFAT 0x82/130 0x7a/122 works