Shift keycodes on the iBook

Segher Boessenkool segher at
Fri Sep 6 09:39:38 EST 2002

Michel Lanners wrote:
> On   3 Sep, this message from Benjamin Herrenschmidt echoed through cyberspace:
> >>> The interesting thing is that was what was believed for years about
> >>> the locking capslock key as well...
> >>
> >>Ah, but that depends on the specific model of keyboard. At least some of
> >>Apple's ADB keyboards _do_ indead have a mechanical capslock.
> >>
> >>I don't know for USB keyboards, but obviously the PowerBook keyboards
> >>have a regular (non-locking) key as capslock. Whether the lock is done
> >>in the ADB driver or in the keyboard controller, I don't know...
> >
> > Actually, the lock itself isn't, but the keycode sent by the PMU behave
> > like a HW lock (and the LED is driven that way too).
> >
> > In both cases, there may be ways to instruct the PMU to behave differently
> > but I don't know about them.
> Anybody up for sucking the PMU firmware out of the little beast and
> reverse-engineering it? Might be a fun project :-))

There's a little program for doing the "sucking" part of this available on
my page at;  Apple was nice enough to include some commands
in the CPU<->PMU interface language for reading any part of the PMU memory.

The PMU is a Mitsubishi MCU; afaik, it's a M30624FGMGP, which is a member of the
M16C/62 family.  Mitsubishi's documentation pages have been much improved
lately; you can actually find the pdf's you need now :)

Reverse engineering something as big as this is quite a bit of work, though;
especially if you don't know which of the 88 i/o lines on the chip are
connected where ;)



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