Packet mode for boot0/mbr

Matthew Dillon dillon at
Wed Jan 7 23:38:43 PST 2009

:I think the hard drive size limitation is around 8GB for CHS.  Any larger=
:drive will have to use packet mode anyways.  The problem is that even for=
:smaller drives/reads below 8GB if OS and BIOS don't agree on CHS, booting=
:won't work.  Packet mode is really a stone old interface by now.
:   simon

    Well, we do have the packet mode flag in boot0 that can be set or
    cleared.  It is set by default by the installer.  I believe that 
    will cause boot0, boot1, and boot2 to use packet mode.  I'm not
    sure about the loader but I think the loader too?

    In anycase, CHS always translates correctly for any sectors in the
    first cylinder.  It's once you get into the second cylinder and beyond
    where problems start to crop up.


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