[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Can't preserve the raw AIS message

From: Gary E. Miller
Subject: Re: Can't preserve the raw AIS message
Date: Thu, 1 Oct 2020 10:34:28 -0700

Yo Owen!

On Thu, 1 Oct 2020 13:04:01 +0100
Owen Mather <> wrote:

> So the data before the !AIVDM is a TAG block as defined by NMEA 0183.
> \s:A01-CS084,c:1600862415,t:LIVE*59\!AIVDM,1,1,,A,38;?cf10008aPTl8G3:P090L0P00,0*2F

Still looks invalid to me.  No line endings, spurious backslashes, no lead
in character.

NMEA starts with a $, AIS starts with a dolar.  Nothing gpsd understands
starts with \s

> (I’m not sure if you’ll be able to see the image below)

I see it, but I don't understand the context.  NMEA != AIS.

> I ran the below so I so I can send data to Gpsd over 62209:
> nc -l 62209 | gpsd -n -N /dev/stdin

Interesting idea.

> Then I sent the following message:
> echo
> '\s:A01-CS084,c:1600862415,t:LIVE*59\!AIVDM,1,1,,A,38;?cf10008aPTl8G3:P090L0P00,0*2F'

As above, invalid message.

> So I believe using -R is meant to give me the full raw, but this
> appears not the case.

Yes, and no.  Without proper line endings and valid chars the rest of your
message is ignored as invalid.

> When I say I want to preserve the part before AIVDM

gpsd throws away invalid data.

> It’s because \s:A01-CS084,c:1600862415,t:LIVE*59\
> provides useful information such as source and time that I want to
> use with the decode message.

No, it is malformed and invalid.

> >> I have an AIS messages as follows
> >> \s:A01-SC084,c:1500862415,t:LIVE*59\!AIVDM,1,1,,A,38;?cf10008aPTl8G3:P090L0P00,0*2F
> >>  
> > 
> > That does not look valid to me.

I've been saying the same thing.  Why ask the same thing and ignore my annswers?

Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703  Tel:+1 541 382 8588

            Veritas liberabit vos. -- Quid est veritas?
    "If you can't measure it, you can't improve it." - Lord Kelvin

Attachment: pgpjqvx3XVhNC.pgp
Description: OpenPGP digital signature

reply via email to

[Prev in Thread] Current Thread [Next in Thread]