Don't ask how to hack password. (BIOS Passwords)
#50977 by boredwild
Mon Nov 10, 2008 12:28 pm
Recommended by Wim's BIOS... BIOS Agent scan: Upgrade your BIOS! DriverMax is the number one driver updater for Windows 8.1, Windows 8, Windows 7, Vista or XP
#50977 by boredwild
Mon Nov 10, 2008 12:28 pm
Had another look at semi's instructions and found another little tutorial on correcting checksums: http://www.xtremesystems.org/forums/sho ... p?t=180607

In a previous post you list your 4 differences: -19 -05 -82 -BD. If you change these to positive values and sum them together, we see that you are changing the checksum by a total of 15D (smaller), so we have to make the checksum of the new bin bigger by 15D. However, we cannot do this in just one hex bit as the largest value is FF. Therefore, we could increase the value of the checksum by changing one "zero" bit to FF and another bit to 15D-FF=5E.

The 68BDD.bin ends in "00 00", so we should be able to stick our "5E FF" in right there. Shouldn't be any active code there, but if it doesn't work, we could try to stick this string in further from the end, amidst the sea of "00"s.

I can't try this yet as I won't be able to get a SMT PLCC socket until next week. Then the first task is to revive the machine...