[Gta04-owner] Making sense of the sensors.
ssj2micvm at gmail.com
Thu Aug 9 23:07:23 CEST 2012
Is the needle going crazy or is it constantly showing in the same
direction if you don't move your device?
On 8/9/12, Benjamin Deering <ben_deering at swissmail.org> wrote:
> I played a bit with valacompass on GTA04. Libsensmon would need a
> BMA150 module for tilt compensation to work, but I commented out the
> accelerometer code in my build.
> The hmc5843 driver for the latest SHR kernel has the sysfs files in a
> different place.
> I changed .Sensmon/config to include:
> The sysfs file 'rate' seems to have changed to sampling_frequency.
> X,Y,and Z values come from separate files. I'm not a vala programmer,
> but I can send what I did to get them.
> I had to adjust in_magn_range to get the Y axis to show anything but
> I don't know how important the tilt compensation is, but with all my
> changes the needle in valacompass does not point north. The direction
> it points seems to change when I rotate the phone, but it is very
> noisy. I think there is some interference from the speaker magnets as I
> was able to get a reading on the Y axis without adjusting the range if I
> brought a magnet near the phone. I have Slyon's 3d printed speaker box
> and 2 speakers, maybe those with a single speaker will have different
> On 08/04/2012 02:10 PM, Michele Brocco wrote:
>> On 8/4/12, NeilBrown<neilb at suse.de> wrote:
>>> The compass seems to have a strong bias on all axes. Presumably some
>>> in the GTA04 (speaker?) needs to be compensated for. Has anyone played
>>> this at all? Figured out how to calibrate, then how to convert the 3
>>> into a compass direction?
>> hi neil,
>> I wrote a proof of concept user space compass application for the
>> navigation board (http://wiki.openmoko.org/wiki/ValaCompass). you can
>> take a look at the source code if you want. i wanted to update the
>> application once the kernel in shr will support this sensor and the
>> accelerometers. but currently I am very busy and could not chek if
>> everything is there already.
>> Gta04-owner mailing list
>> Gta04-owner at goldelico.com
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