Magic Lantern Firmware Wiki

EXFAT rerated stuf

328pages on
this wiki
Add New Page
Talk0 Share

As we alter EXFAT we need to fix the checksum.


1. Sector 0: write EOS_DEVELOP (from 0x82) and BOOTDISK (from 0x7a)

2. Calculate checksum: chks:=0; for i:=0 to 5631 do if (i<>106) and (i<>107) and (i<>112) then chks:=(chks shr 1)+(chks shl 31)+buf[i];

Note: This is incorrect!  it should be chks ROTATE_RIGHT 1 and chks ROTATE_LEFT 31. Do not use SHIFT!

3. Sector 11: (from 0x1600, 5632 ) write the calculated checksum 128 times (fill the whole sector with the 4 byte checksum value)

4. Sector 12: Copy Sector 0 here

5. Sector 23: Copy Sector 11 here

Ad blocker interference detected!

Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.

Also on Fandom

Random Wiki