AIS Targets Disappear After a Longer Period

[mrm]

Originally Posted by cagney

mrm

Are you aware of the VDR, voyage data recorder, plugin?
PlugIns | Official OpenCPN Homepage

Thomas

Thomas, I wasn't aware...

Anyway, it was a nice short project and exercise, and is app agnostic which may be a plus.

Marius

[cagney]

Marius

OK!
Just keep on hacking!

Thomas

[sinbad7]

mrm..

OK,thanks Marius....I will await solutions...

Tore

[PjotrC]

Originally Posted by sinbad7

I will await solutions...

Don't await... try to isolate...

I have Vista and I'm quite sure the contents of your NMEA stream is not at fault here...

[sinbad7]

PjotrC..

Don't quite know what you mean by 'isolate' but I am also positive the NMEA data loss is an OpenCPN programing error as it works perfectly with other nav. progs. such as Fugawi ENC Marine etc.

Hope Dave will have a look at it when he returns from his cruise.

I am sure there are many out there still on Vista with a potential dangerous situation at the sudden disappearance of their NMEA data.

Tore

[bdbcat]

Hi all....

I'm back, in a low bandwidth sort of way...

Any progress on isolating this Vista AIS dropout problem?
My suspicions lie in the Vista serial port support code, but are unproven.
Anyone else with Vista and SR161/162 receiver?

MRM: Your idea to send NMEA data to OCPN would have worked just fine with a FIFO if you had known about an undocumented backdoor inserted for just this purpose.

see the code in ais.cpp

  /*
     A special test for a user defined FIFO
     To use this method, do the following:
     a.  Create a fifo            $mkfifo /tmp/aisfifo
     b.  netcat into the fifo     $nc {ip} {port} > /tmp/aisfifo
                     sample {ip} {port} could be  nc 82.182.117.51 6401 > /tmp/aisfifo
     c.  hand edit opencpn.conf and make AIS data source like this:
          [Settings/AISPort]
          Port=Serial:/tmp/aisfifo

    This also works if you have an ascii ais log
    for which you can simply $cat ais.log > /tmp/aisfifo
    */
    if(m_pPortName->Contains(_T("fifo")))
          goto port_ready;

You may see that if the port name contains the string "fifo", then the requirement for the port to be a TTY is relaxed.

Sorry you had to code around this "feature", but as usual I code faster than I document....

Dave

[Jon Hacking]

We used an SR161 for 4 years, but on XP & Win7, not Vista. But I suspect the culprit is the Serial-USB converter. I've had more problems getting GPS info into friends computers because of poor converters. The problem is that RS232 Serial is a +/-9v signal, & NMEA is a 0-5v signal. A good Serial-USB converter will handle this fine, but a poor one won't. We've used a KeySpan 4-port Serial-USB converter for 5 years with no problems at all. It cost 2x what the others did, but it works!

[sinbad7]

Dave..

As mentioned earlier in this thread,I'm on Vista Basic.
Querying the AIS targets as well as the Target List aborts OCPN.
AIS targets are also lost after a period of time (45 min or so)

I have normal operation using Fugawi Marine ENC..

Tore

[sinbad7]

I've made a rather strange observation regarding displayed AIS targets in Vista. If you minimize the OCPN screen,the targets do not disappear,as they do after a longish period in a full screen.

Tore

[sinbad7]

The new beta v. 2.6.1511 has corrected the AIS queery problems but the AIS data is still being removed after a longer period.

I tested the incoming AIS data for a long period with AIS Despatcher and all was working normally,no data loss. It also works perfectly with Fugawi ENC Marine.

Tore

[sinbad7]

Another anomaly with v. 2.6.1511 is that whilst NO AIS targets are visible,a queery of the AIS Target List shows all of 7 vessels?

Tore

[cagney]

Originally Posted by sinbad7

Another anomaly with v. 2.6.1511 is that whilst NO AIS targets are visible,a queery of the AIS Target List shows all of 7 vessels?

Tore

Tore
The possibility exists that these targets are outside the screen but still within the set 40M limit. You maybe right, but the screen dump is not sufficient proof.
Thomas

[LeaseOnLife]

Originally Posted by sinbad7

Another anomaly with v. 2.6.1511 is that whilst NO AIS targets are visible,a queery of the AIS Target List shows all of 7 vessels?

Tore

Tore

could you post two screenshots, like the one you just posted, with the AIS target list window open:
1) before the AIS targets disappear
2) after the AIS targets have disappeared

Hopefully the ships are in about the same position for both screenshots.

Both screenshots should show the same location, at the same scale.

Dirk

[sinbad7]

Thomas..

Of course I am aware of the fact that AIS targets displayed in the AIS target list may not be visible on the map outside of the used scale.

I have cases where NO targets are showing at all,or the number of targets do not correlate with the target list.

The next to last screen shot after a period of 2 hours shows ALL targets removed from both the AIS listing as well as from the screen.

Tore

[sinbad7]

Again,after a few minutes,all the AIS targets disappeared from my screen,only the AIS Target list still shows the targets. Only by re booting OCPN did the same targets reappear on screen as well as in the AIS Target list.

There is nothing wrong with either my SR162 receiver or the RS232/USB cable,as all targets arrive continuously in both Fugawi ENC Marine as well as in my AIS Dispatcher utility as can be seen from the attached AIS data file.

A potentially dangerous situation navigating in a busy area when ALL targets suddenly disappears from your screen.

Tore