DragonFly On-Line Manual Pages
APS(4) DragonFly Kernel Interfaces Manual APS(4)
aps -- ThinkPad Active Protection System accelerometer
To compile this driver into the kernel, place the following lines in your
kernel configuration file:
device aps0 at isa? port 0x1600
Alternatively, to load the driver as a module at boot time, place the
following line in loader.conf(5):
The aps driver provides support for several sensors found in some
The sensors currently supported are:
Sensor Units Typical Use
X_ACCEL Unknown X Acceleration
Y_ACCEL Unknown Y Acceleration
X_VAR Unknown Weighted X Acceleration?
Y_VAR Unknown Weighted Y Acceleration?
Temp1 uK Unknown
Temp2 uK Unknown
Keyboard Active boolean Keyboard activity
Mouse Active boolean Mouse activity
Lid Open boolean Lid state
Sensor values are made available through the HW_SENSORS sysctl(3) inter-
face, and can be monitored with the systat(1) sensors display,
sensorsd(8) and sysctl(8) hw.sensors. For example, on a ThinkPad R51:
hw.sensors.aps0.raw0: 488 (X_ACCEL)
hw.sensors.aps0.raw1: 481 (Y_ACCEL)
hw.sensors.aps0.raw2: 488 (X_VAR)
hw.sensors.aps0.raw3: 481 (Y_VAR)
hw.sensors.aps0.temp0: 52.00 degC
hw.sensors.aps0.temp1: 52.00 degC
hw.sensors.aps0.indicator0: Off (Keyboard Active)
hw.sensors.aps0.indicator1: Off (Mouse Active)
hw.sensors.aps0.indicator2: On (Lid Open)
systat(1), sysctl(3), intro(4), isa(4), sensorsd(8), sysctl(8)
The aps driver first appeared in OpenBSD 3.8. DragonFly support was
added in DragonFly 2.5.
The aps driver was written by Jonathan Gray <firstname.lastname@example.org>. It was
adapted to DragonFly by Constantine A. Murenin, University of Waterloo.
The aps driver does not yet maintain state and subsequently does not take
evasive action when it thinks the hard drive is in danger.
The Y axis on X40 and possibly other models seems to be inverted. It is
unknown how to distinguish between different versions of the accelerome-
ter to compensate for this in the driver at this time.
As IBM provides no documentation, it is not known what all the available
sensors are used for.
DragonFly 3.9 March 18, 2010 DragonFly 3.9