Add the Shearwater Nerd 2 bluetooth device name.
The change to uppercase is purely cosmetic. The string comparisions are
not case-sensitive. But for documentation purposes it's good practice to
list the exact name as reported by the device.
It's exactly the same as the regular i200, but has a new version number
and string.
Tested-by: Tiago Thedim Dias <tiagotsoc@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The Mares Genius supports a new command to download different types of
objects (e.g. dive header, dive profiles, etc) directly, without needing
to manually read and parse the contents of the flash memory.
The data structure also changed significantly. The profile data is now
organized into different records. Each record starts and ends with a 4
byte ascii marker:
DSTR: Dive start record
TISS: Tissue record
DPRS: Sample record
AIRS: Air integration record
DEND: Dive end record
and contains a CRC checksum. The contents of the records remains very
similar to the existing iconhd data format.
Based-on-code-by: Janice McLaughlin <janice@moremobilesoftware.com>
The main difference with the serial communication is that the BLE
communication uses data packets (with a maximum size of 20 bytes)
instead of a continuous data stream.
Occasionally, the device responds with an empty packet (with just the
ACK and EOF byte) or with a short packet where one or more payload bytes
are missing. The empty packet is most likely caused because the device
didn't receive the second part of the command (with the parameters) in
time. The missing bytes might be caused by a buffer overflow on the
Bluelink Pro, when the data from the dive computer arrives faster over
the serial link than the device can forward it over the slower bluetooth
link to the host system.
One way to address this problem is to lower the packet size from 256 bytes
to only 128 bytes. The main disadvantage is that this also impacts the
download speed considerably. In one particular example, the total
download time increased from about 135 to 210 seconds (which is already
slow compared to the 62 seconds the same download takes over usb)!
An alternative solution is to simply retry the failed command. That way
there is only a performance penalty for the few bad packets, and not for
every single packet. In the above example, only two packets needed a
retransmission.
Note that the iconhd communication protocol uses no checksums. Hence
it's not possible to detect corrupt data packets. Only short packets can
be detected, because they result in a timeout.
There were quite a few models missing in the list. And because the
lowest iX3M model number has changed, the iX3M detection needed to be
updated as well.
It appears that the Aqualung i770R looks almost the same as the Pro Plus
X, but has an additional pO2 field for each gas by the O2 field, which
impacts the offset calculations.
The Smart Air uses almost the same data format as the Quad Air. Only the
4 bytes containing the dive mode and number of samples moved from the
beginning of the header to the end. This is a change adopted from the
regular Smart.
The Oceanic Pro Plus X is quite different from the previous models. The
profile data is now stored in a dedicated memory area, and hence there
are a few important differences:
Reading data from the new profile memory area is done with a new F6
command. This new command is very similar to the existing B8 command,
but accesses a completely different memory area. In order to integrate
those two memory areas as transparantly as possible into the existing
infrastructure, a virtual memory space is introduced. The lower part of
the virtual memory is mapped onto the main memory area, while the upper
part is mapped onto the new profile memory area.
The page size of the new profile memory area also increased from 16 to
256 bytes. If the profile size is not an exact multiple of 256 bytes,
the dive computer pads the profile data with 0xFF bytes.
The other changes are the usual Oceanic device specific changes.
The Uwatec Smart, Meridian and G2 backends are almost identical, except
for the low-level packet sending and receiving code. With the new I/O
layer, those three backends can easily be unified in a single backend.
The Meridian and G2 are completely removed, only the family types are
kept for backwards compatibility.
The main difference with the serial communication is that the BLE
communication transmits each SLIP encoded data packet as one or more BLE
data packets. The BLE packets have an extra two byte header with the
total number of packets and the current packet number.
The main difference with the serial communication is that the BLE
communication uses data packets (with a maximum size of 20 bytes)
instead of a continuous data stream.
The main difference with the USB HID communication is that the BLE data
packets have a variable size and are no longer padded to the full 32
(Tx) or 64 (Rx) bytes.
The main difference with the USB HID communication is that the BLE data
stream is encoded using HDLC framing with a 32 bit CRC checksum. Due to
this encoding, the data packets can no longer be processed one by one
(as is done for the USB HID packets). The entire HDLC encoded stream
needs to be received before it can be processed. This requires some
additional buffering.
With the support for multiple transports per device, the
dc_descriptor_get_transport() function became obsolete because it does
support only a single transport type. Applications should use the new
dc_descriptor_get_transports() function instead.
With the support for multiple transports per device and the possibility
to use custom I/O implementations, libdivecomputer no longer knows which
devices are actually supported. Hence libdivecomputer needs to always
report all the devices it knows about, and it's up to the application to
filter out entries for which there is no suitable transport available
(either built-in or custom).
Several dive computers support multiple transports. For example the
Suunto Eon Steel supports both USB HID and BLE. All devices using
bluetooth classic communication support both the native bluetooth
transport and the legacy serial port emulation.
To support this feature, the values of the dc_transport_t type are
changed into bitmasks, and the dc_descriptor_t struct is extended with a
bitfield with all the supported transports.
The device descriptors are extended with a filter function. During the
device discovery, this filter function is used to return only devices
that match a known dive computer.
The filtering is optional, and can be disabled by passing a NULL pointer
for the device descriptor when creating the iterator with one of the
dc_xxx_iterator_new() functions.
Unlike the Shearwater Petrel, the Shearwater Nerd 2 appears to have a
distinct model number from the Nerd.
Reported-by: Janice McLaughlin <janice@moremobilesoftware.com>
The Suunto Eon Core uses a different USB PID, but otherwise it's
compatible with the Eon Steel. It's probably an Eon Steel internally,
but with a smaller form factor.
To be able to distinguish between the two models and use the correct USB
PID, each model is assigned a different (artificial) model number.
Reported-by: Nick Shore <support@mac-dive.com>
