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aduvenhage / ais-decoder

C++ AIS Decoder (with python bindings)
MIT License
29 stars 11 forks source link

Multi-fragment sentence #3

Open sihnatse opened 4 years ago

sihnatse commented 4 years ago

A problem with the following messages from Transas simulator:

!AIVDO,2,1,7,,53`t?>@2Dvop4i0P400u>3<0000000000000001JD@>D:3?00Gh00000000,0*7C
$AITXT,1,1,22,AIS: external GNSS in use*41

Might be wrong but still get parsed fine by maritec.co.za

The second one complains on CRC.

aduvenhage commented 4 years ago

Thank you for the feedback. Added support for leading '$' on sentences, but AIS decoder still does not support decoding this type of string.

What are your requirements? Also, are you using this from Python or C++?

sihnatse commented 4 years ago

I suspect that the problem goes beyond this project. The sentences above might be non-standard, bounded to Transas simulator only. (Note that I am not mariner nor have experience with navigation equipment.) So, potentially, very limited usage. BTW - it gets parsed by SEAiq also.

Nothing special regarding requirements.

C++

sihnatse commented 4 years ago

UPDATE: You might well discard this issue. The original problem relates to the second fragment of a multi-fragment message being missed. This is caused by Windows sockets, at least in their current implementation in UWP. Other devices parse AIS feed fine because of either running under different OS (MacOS and iOS) or having different connection. It would be still nice if you add $AITXT support, but not vital for my project - I'm satisfied with existing functionality. Thanks!