AIS problems with shipnames

[Bill O]

Originally Posted by Bill O

Do the names come up on the AIS Target List (available thru right click menu). If so, then most likely a display issue

Bill O.

Did you check the AIS target list? Was all the info there?


Bill O.

[Valoroso]

Originally Posted by Bill O

Did you check the AIS target list? Was all the info there?


Bill O.

No, info was not in AIS target list.
It's going wrong during data parsing.
I think that I loose one character in the NMEA to WIFI bridge only with message 5.

[did-g]

Originally Posted by Paul Elliott

I was able to decode this with NavMonPc. It is a compound sentence, both parts are required. The first one had a bad checksum (the single digit "1", it should have been "37"), so I set NavMon to fix bad checksums. The second part did have a valid checksum.

NavMon shows these details -
name: "CUPIDO /0"
Callsign: OTY4222
mmsi: 205422290
Length: 1604 ft (converted from meters by NavMon)

Here are the cleaned-up sentences:
!AIVDM,2,1,5,A,533qvlT00000uCC;;:0=E0T@v2222222222 2221?=h0564U<?03kPQBiCQ88,0*37
!AIVDM,2,2,5,A,88888888880,2*21



I stripped out the <GREEN> and the "<0x0D><0x0A>" stuff. Could this, or the bad checksum be the problem?

I couldn't get that website decoder to work, even after correcting the parity. Here's one that did decode it: https://www.maritec.co.za/tools/aisvdmvdodecoding/

first message size is 81+ 1 or 2 (cr or crlf)
and there's a
AIS_Bitstring.h:
#define AIS_MAX_MESSAGE_LEN (10 * 82) // AIS Spec allows up to 9 sentences per message, 82 bytes each



A little bit too close for comfort.

Could you capture the network traffic?

[Valoroso]

Originally Posted by did-g

first message size is 81+ 1 or 2 (cr or crlf)
and there's a
AIS_Bitstring.h:
#define AIS_MAX_MESSAGE_LEN (10 * 82) // AIS Spec allows up to 9 sentences per message, 82 bytes each



A little bit too close for comfort.

Could you capture the network traffic?

I'm working on that.
At the moment I have captured data from the transponder.
I am able to send it via a USB to serial converter to the NMEA2WIFI bridge.
I can reproduce the problem.
Now I am looking for software to catch the data from the UDP socket without OpenCPN.
Suggestions are welcome.

[nohal]

Originally Posted by Valoroso

Now I am looking for software to catch the data from the UDP socket without OpenCPN.
Suggestions are welcome.

tcpdump, wireshark/tshark

[Valoroso]

The problem is solved.
I did a test with an app on my phone and the last character was allready missing in the data.
I raised this problem at the supplier from the NMEA2WIFI bridge.
For him it was a know problem.
I upgraded the software in the NMEA2WIFI bridge and the problem was solved.

Thanks again for all the comments

[Bill O]

Originally Posted by Valoroso

The problem is solved.
I did a test with an app on my phone and the last character was allready missing in the data.
I raised this problem at the supplier from the NMEA2WIFI bridge.
For him it was a know problem.
I upgraded the software in the NMEA2WIFI bridge and the problem was solved.

Thanks again for all the comments

Glad you could solve the problem and good thinking to contact the supplier to see if it was a known problem.


Bill O.