NAME
pmu
- support for Power Management Units found in all Apple laptops and some
desktop Power Macintosh computers
SYNOPSIS
pmu* at obio?
nadb* at pmu?
battery* at pmu?
smartbat* at pmu?
DESCRIPTION
The
pmu
driver provides support for the Power Management Unit found in
Apple laptops and some desktop Power Macintosh computers.
Functions controlled by the PMU include the real time clock, ADB,
power, batteries, on some laptops like the PowerBook 3400c and
similar machines it also controls hotkeys and display brightness,
on others it provides an
iic(9)
bus and on some it controls CPU speed.
On many older machines it also provides access to some non-volatile
memory and thermal sensors.
Not all those features are present on all machines, for instance
Power Macintosh G4 and later machines don't have ADB, many more
recent laptops have display brightness and backlight control built
into the graphics controller instead of the PMU, only a few older
PowerBooks use the PMU for CPU speed control and newer machines
use a different way to access non-volatile memory.
However, all known PMUs so far provide a real time clock and power
control.
Notes by model
Real time clock and power control are present and supported on all
machines that can run
NetBSD/macppc,
ADB is supported when present.
PowerBook
2400,
3400c,
and
3500
-
Battery status and thermal sensors found on the mainboard and in
the battery pack are supported by the
battery(4)
driver, values can be read via
envsys(4).
Hotkeys for brightness control are supported, CPU speed control
and parameter RAM are present but unsupported.
Power
Macintosh
G4
-
ADB is not present,
iic(9)
is present but unsupported.
SEE ALSO
battery(4),
cuda(4),
nadb(4),
nvram(4),
obio(4),
iic(9)
BUGS
Some features are currently unsupported, like the
iic(9)
bus, access to parameter RAM and CPU speed control.