Not only the two byte end-of-profile marker 0xFDFD is a valid empty dive
profile, but also a profile with the length field present and set to 8
bytes. In that case the actual length will be just 5 bytes.
For dive computers where the reference time (epoch) of the device is
unknown, libdivecomputer uses the current time of the device (devtime)
and the host system (systime) to synchronize both clocks.
Currently, both timestamps are passed directly to the constructor of the
parser. With the new public function, the application can adjust the
timestamps afterwards.
Some dive computers store the depth as an absolute pressure value (in
bar). To convert to a depth value (in meters), the atmospheric pressure
and water density are required. For dive computers that do not have
those values available, libdivecomputer uses a default value. With the
new public api functions, applications can adjust those default values.
Some dive computers already provided a backend specific calibration
function. Those functions are now deprecated. They are kept around to
maintain backwards compatibility for now, but they will be removed in
the next version.
Report the decompression algorithm (Buhlmann, VPM, RGBM or DCIEM), and
if available also the parameters. For now only the conservatism setting
is supported, and for the Buhlmann algorithm also the Gradient Factors
(GF).
In recent hwos firmware versions, the depth is no longer stored as
pressure (in millibar), but directly as depth (in meters) with the
salinity and gravity factor already applied.
Due to a bug in the hwOS Tech firmware v3.03 to v3.07, and the hwOS
Sport firmware v10.57 to v10.63, the ppO2 divisor is sometimes not
correctly reset to zero when no ppO2 samples are being recorded.
Usually this condition can be detected by the fact that the length of
the extended sample will not have enough space left for the ppO2 sample
(9 bytes). As a workaround, reset the divisor back to zero to manually
disable the ppO2 samples.
In theory this detection method is not 100% reliable. There can still be
other sample types present in the extended sample. If their total size
is larger than 9 bytes, the bug will not be detected at all. Instead,
those bytes will get interpreted as the ppO2 sample, resulting in bogus
ppO2 values. Additionally, one of the other sample types will now run
out of space and cause the parsing to fail with an error. However, in
practice this risk is relative low. Most of the other samples are
relative small (1 or 2 bytes), so you would need many of them. That's
rather unlikely in most configurations. The only exception is the large
deco plan sample (15 bytes).
In commit 2829f7ebf9902170bf653d67dbe412a0a4f140cf, the hwos parameter
of the hw_ostc_parser_create() function was kept to preserve backwards
compatibility. Since the function has been removed from the public api,
the parameter can be removed now.
The workaround for the tank pressure in the previous commit is only
relevant for the newer hwOS based devices, and not for the original OSTC
devices. In practice this doesn't cause any problems because the
original OSTC doesn't support a tank pressure sensor, but nevertheless
it's better to use the correct condition.
The tank pressure is stored with a resolution of 1 bar instead of 0.1
bar. There is however one exception. The hwOS Sport firmware used a
resolution of 0.1 bar between versions 10.40 and 10.50.
Unfortunately the only way to distinguish the Sport from the Tech
variant is the different range of the version number (10.x vs 3.x). The
consequence is that this workaround will start to produce wrong results
once the firmware version number of the hwOS tech variant reaches the
10.x range. If that ever happens, this workaround should be removed
again!
For older OSTC dives, using logbook format version 0x20, the average
depth is not available in the dive header. It's only available since
version 0x21, which increased the header size from 47 to 57 bytes.
Add a new type to distinguish between closed circuit (CCR) and
semi-closed circuit (SCR) diving. Some dive computers from HW and
DiveSystem/Ratio support this.
Because the CCR/SCR abbreviations are more commonly used, let's take the
opportunity to also rename the existing DC_DIVEMODE_CC. To preserve
backwards compatibility, a macro is added to map the old name to the new
one.
Reported-by: Jan Mulder <jlmulder@xs4all.nl>
The OSTC3 stores the dive headers and profile data in two separate
memory areas. There is a header area with fixed positions and a profile
area which is used as a ring buffer. Each dive header stores the
position of the profile data in the ring buffer.
Now, once there are more dive headers then room for the profiles, the
oldest profiles (but not the headers) are overwritten with new data.
Because the dive headers are not updated when their profile data gets
overwritten, they will now point to data that is no longer available.
The internal logbook detects this situation and does not display the
profile. But during the download, there is no such check, and the OSTC
will send invalid profile data.
This invalid profile data should be dropped on the receiver side.
Unfortunately implementing the exact same check as is done by the OSTC
itself isn't possible, because the OSTC doesn't send the 6 byte internal
header on which the check is based. As a workaround, the two byte
end-of-profile marker and the length field in the profile header is used
to detect overwritten profiles.
As the OSTC does not report a CNS value on the first sample, we need to
initialize it differently. This can be solved by using the initial CNS
value form the dive header, and storing that value in the first sample.
The resulting patch is very similar to 44f629f03a91a3b3.
Signed-off-by: Jan Mulder <jlmulder@xs4all.nl>
The main purpose of the magic value UNDEFINED, is to indicate that a
value isn't present in the data. But since the value 0xFF can actually
be stored in the data, we can't distinguish between those two cases.
This ambiguity can be avoided by using a magic value that lies outside
the valid range for 8 and 16 bit fields.
Note that an initial gas mix value of 0xFF remains interpreted as
UNDEFINED, but this is now made explicit.
Allthough most dive computers always use local time and don't support
timezones at all, there are a few exceptions. There are two different
sources of timezone information:
- Some of the newer Uwatec/Scubapro devices use UTC internally and also
support a timezone setting. This UTC offset is currently taken into
account to obtain the dive date/time, but the UTC offset itself is
lost.
- Uwatec/Scubapro and Reefnet devices rely on the clock of the host
system to synchronize the internal device clock and calculate the
dive date/time. The consequence is that the resulting date/time is
always in the timezone of the host system.
In order to preserve this timezone information, the dc_datetime_t
structure is extended with a new "timezone" field, containing the UTC
offset in seconds. Devices without timezone support will set the field
to the special value DC_TIMEZONE_NONE.
The dc_datetime_localtime() and dc_datetime_gmtime() functions will
automatically populate the new field with respectively the local
timezone offset and zero. The dc_datetime_mktime() function will take
into account the new timezone field for the conversion to UTC. The
special value DC_TIMEZONE_NONE is interpreted as zero.
In CCR fixed setpoint mode of the OSTC3, the initial setpoint at the start
of the dive was not set. This fix adds the initial setpoint based on
the data in the fixed setpoint table (ie, the first fixed setpoint is
the initial one).
Signed-off-by: Jan Mulder <jlmulder@xs4all.nl>
The vendor_product_parser_create() and vendor_product_device_open()
functions should be called indirectly, through the generic
dc_device_open() and dc_parser_new() functions. And the
vendor_product_extract_dives() functions are internal functions that
should never have been part of the public api in the first place.
In the public header files, all symbols are marked extern C. When using
a C compiler, there is usually no problem if the header isn't included
in the C file. But the msvc build system uses the C++ compiler (due to
the use of some C99 features not supported by the msvc C compiler).
Due to a firmware bug, the deco/ndl info is incorrect for all OSTC4
dives with a firmware older than version 1.0.8. Since it's not possible
to correct the info again, it's ignored and not returned to the
application.
To be able to pass the OSTC 3 model number to the parser, and preserve
backwards compatibility, we need a new function. The new function should
also be used for the Frog, by passing zero as the model number.
Using the hw_ostc_parser_create() function with the hwos parameter set
to one, is now deprecated but will remain supported for backwards
compatibility.
The frog parameter and field are not only used for the Frog, but also
for all hwOS based models. Therefore, using the more generic hwos as the
name is more meaningful.
For the OSTC3 compatible devices, a missing initial gas mix (e.g. no gas
marked as the first gas) leaves the initial gas mix index at its default
value of zero. This is different from the OSTC2 compatible devices,
where a missing initial gas is stored as the value 0xFF.
By initializing the index with the value 0xFF, the existing detection
works for both variants.
Both the allocation and initialization of the object data structure is
now moved to a single function. The corresponding deallocation function
is intended to free objects that have been allocated, but are not fully
initialized yet. The public cleanup function shouldn't be used in such
case, because it may try to release resources that haven't been
initialized yet.
Instead of freeing the object data structure in the backend specific
cleanup function, the memory is now freed automatically in the base
class function. This reduces the amount of boilerplate code in the
backends. Backends that don't allocate any additional resources, do no
longer require a cleanup function at all.
The new gasmix sample contains the index of the active gas mix.
This new sample is intended as a replacement for the existing gas change
events (SAMPLE_EVENT_GASCHANGE and SAMPLE_EVENT_GASCHANGE2). To maintain
backwards compatibility, the legacy events are marked as deprecated but
not removed yet.
In CC mode, only the diluents are stored in the header. The list with
the OC gas mixes, which are used for bailout, are not stored in the
header. In order to retrieve the bailout mixes too, we need to parse the
profile and add them to the manual gas mixes.
In some rare cases, the initial gas mix contains the value 0xFF. This
value is obviously outside the expected range (1-5), and therefore
causes the parsing to fail. It's not really clear how this can happen.
As a workaround for the fatal error, we now ignore the invalid value and
simply proceed without a gas mix.
Even if there are no O2 sensors connected (for example in auto or fixed
setpoint mode), the device records a ppO2 sample with all three values
set to zero. Such samples are now ignored, as if there was no ppO2
sample present.
Reported-by: Anton Lundin <glance@acc.umu.se>
When the PPO2 sample was introduced, we didn't take into account the
fact that rebreathers usually support multiple O2 sensors. The HW OSTC
supports for example three sensors. In order to support multiple values,
without having to introduce a new data structure with an additional
sensor id field, we simply relax the assumption of allowing only one
DC_SAMPLE_PPO2 value per sample. Applications that are not prepared for
multiple values, will automatically use only one of them (probably the
last one).
The DC_FIELD_GASMIX api doesn't support the 6th manual gas very well.
Manual gas mixes are either not taken into account at all (OSTC3), or
only the last value is returned (OSTC2).
We now parse the profile data in order to retrieve all the manual gas
mixes too. Note that manual gas mixes are only included when they are
actively used during the dive. This is a small change in behaviour for
the OSTC2.
To simplify the implementation, there is an upper limit of 10 manual gas
mixes (or 15 gas mixes in total). This is an arbitrary choice, which
should be more than sufficient in practice. If it turns out to be too
small, we can always increase the number, or even make it truely
unlimited.
