the previous approach assumed a 1:1 mapping between compass backends
and compass instances, which isn't true on PX4.
It also only setup milligauss offsets on a set_and_save call, which is
not the only way offsets change
this adds a milligauss_ratio per instance, which is considerably
simpler
AK8963 is configured in 16-bit ADC mode which implies sensitivity of 0.15 uT/LSb. Knowing this fact we can convert the measurements to the proper units. The change will make users recalibrate their compasses.
From now on there's a pair get_field_milligauss() and
get_offsets_milligauss() that can make the transition to the common
units across all compasses easier.
This commit changes the way libraries headers are included in source files:
- If the header is in the same directory the source belongs to, so the
notation '#include ""' is used with the path relative to the directory
containing the source.
- If the header is outside the directory containing the source, then we use
the notation '#include <>' with the path relative to libraries folder.
Some of the advantages of such approach:
- Only one search path for libraries headers.
- OSs like Windows may have a better lookup time.
Don't use a state machine in AK8963: the start_measurements() method
should be called only once. Even if there's a magnetic sensor overflow
the only thing we should do is to discard the new data.
This also moves the _collect_samples() method to be inside _update()
since it's the only place it should be called from, the one running on
the timer thread.
We need to check the AK8963's id before anything else Here we are
reordering the calls to _calibrate() and _check_id(). After that we
don't need to read and write again the AK8963_CNTL1 register.
While at it do some renames as well:
- _configure() -> _setup_mode(): since now there's a
_bus->configure() it became confusing what actually it's
doing.
- make error messages say what we were actually trying to do but
couldn't. Also remove PSTR since this is linux-only.
- start_conversion() -> start_measurements(): We are instructing the
bus to start to get the samples, not to tell the chip to start an
analog->digital conversion like in other sensors.
Similar code was added in the read_raw() implementation for each bus.
Add a new POD struct read_raw to contain the registers from the AK8963
and use it instead as argument.
Andrew Tridgell
Staroselskii Georgii
Lucas De Marchi
Gustavo Jose de Sousa
Julien BERAUD
Víctor Mayoral Vilches