Socket Output Format

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DaveReid
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Post by DaveReid » April 29th, 2008, 6:53 am

edgy31 wrote:Has anyone ever received a "MSG,7,..." output?

I've been listening for a couple days and haven't seen one, so I'm suspecting it's not used??
Kinetic describe MSG type 7 as an "AirToAirMessage" containing just altitude, which sounds like a TCAS DF0/DF16 to me - and we now know (thanks to Boris :D ) that the SBS doesn't pass DF0 or DF16s to the PC.

Provision for a future enhancement, perhaps ?
Dave Reid
Reading, Berks
www.civilaircraftregisters.org/Mode_S_Resources

DaveReid
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Post by DaveReid » April 29th, 2008, 7:01 am

GAZZ22 wrote:Can anyone provide all the fields for the msgs CLK and STA???
CLK doesn't contain any useful information, it simply records the fact that you have double-clicked on an aircraft to bring up the Aircraft Details. You need to look at the last SEL message to see which is the aircraft concerned.

STA shows changes in the status of aircraft on the BaseStation screen, specifically:

AD - added
RM - removed
PL - position lost
SL - signal lost
OK (presumably following an interim PL or SL)

HTH
Dave
Dave Reid
Reading, Berks
www.civilaircraftregisters.org/Mode_S_Resources

edgy31

Post by edgy31 » April 29th, 2008, 12:13 pm

DaveReid wrote:Kinetic describe MSG type 7 as an "AirToAirMessage" containing just altitude, which sounds like a TCAS DF0/DF16 to me - and we now know (thanks to Boris :D ) that the SBS doesn't pass DF0 or DF16s to the PC.

Provision for a future enhancement, perhaps ?
I think so. I was writing a little socket processor, and once you get rid of all the poop on the line (MSG,8 for example) it is a lot more manageable :!:

I think the MSG,8 must be in response to DF11, and around here the FAA uses Mode-S radars like ATCRBS radars. They just ask everyone to reply (allcall), rather than any selective interrogations. Since I have two Mode-S radars in view, I get a ton of MSG,8 data.

DaveReid
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Post by DaveReid » April 29th, 2008, 2:38 pm

edgy31 wrote:I think the MSG,8 must be in response to DF11, and around here the FAA uses Mode-S radars like ATCRBS radars.
Yep, MSG Type 8 is definitely the DF11 All-Call Reply.

Your earlier tip about using the hex codes in the DF11s to help filter out invalid codes in other DFs works well, by that way.
Dave Reid
Reading, Berks
www.civilaircraftregisters.org/Mode_S_Resources

edgy31

Post by edgy31 » April 29th, 2008, 3:09 pm

DaveReid wrote:Your earlier tip about using the hex codes in the DF11s to help filter out invalid codes in other DFs works well, by the way.
Something I suggested works??!!

That's what I've been planning on doing; adding each DF11 hex to a priority queue with a time delta (60 seconds or 6 scans of the LRR radar and 24 scans of the Approach radar). That way they time out and disappear, or get updated with a new 60 seconds. Then compare the other hex codes against that table. Sort of a scan to scan detection filter.

Right after I get done laying 360 sq ft of floor in my shop :twisted:

egnx
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Post by egnx » April 29th, 2008, 6:45 pm

Going back a few posts, in an attempt to clear up some confusion of mine and perhaps others ? it seems to me that the STA - AD messages are not "Added" but are actually "Deleted" ?

Cheers
egnx

DaveReid
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Post by DaveReid » April 29th, 2008, 7:21 pm

egnx wrote:Going back a few posts, in an attempt to clear up some confusion of mine and perhaps others ? it seems to me that the STA - AD messages are not "Added" but are actually "Deleted" ?
Yes, you're quite right, AD means aircraft deleted after the Delete timeout has elapsed.

There isn't a status message for an aircraft being added to the list - that's what the AIR message is for.

Dave
Dave Reid
Reading, Berks
www.civilaircraftregisters.org/Mode_S_Resources

edgy31

Post by edgy31 » May 23rd, 2008, 2:06 pm

Interesting, my socket reading algorithm kept blowing up when reading callsigns of MSG,1. I'm using a simple split() function which loads all the comma separated values (CSV) into individual tokens. Turns out some planes transmit or squitter a callsign that is null. Java hates nulls :shock:

edgy31

Post by edgy31 » July 19th, 2008, 7:09 pm

It's probably common knowledge, but it's not written in this sticky...

The socket data outputs a -1 for true, and a 0 for false. A null means it is not used.

DaveReid
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Re: MODE S and MSG 5 MSG 6

Post by DaveReid » December 22nd, 2008, 5:59 pm

vk4tec wrote:What is the DF for MSG 5 and MSG 6 ?

I was looking closely and some data from socket 30003.

I saw that the height was always in a MSG 5 or MSG 6.

If a MSG 6 got missed, or was not asked for, the MODE A code did not come down for that scan.

Comments ?
Not entirely sure I understand the question, but MSG 5 (described by Kinetic as SurveillanceAltMessage) is from the DF4/DF20 (with/without Comm-B parameters) and MSG 6 (SurveillanceIDMessage) comes from the DF5/DF21 (ditto).

I assume that BaseStation simply inserts the most recently received altitude (which may be from a DF4/DF20 or a squitter) into the MSG 6.
Dave Reid
Reading, Berks
www.civilaircraftregisters.org/Mode_S_Resources

edgy31

Re: MODE S and MSG 5 MSG 6

Post by edgy31 » December 22nd, 2008, 9:26 pm

vk4tec wrote:What is the DF for MSG 5 and MSG 6 ?

If a MSG 6 got missed, or was not asked for, the MODE A code did not come down for that scan.
The answer, is that there is limited association between DF's and MSG's.

MSG 5 and 6 have altitude duplicated, MSG 6 has Squawk and Emergency bit. Msg 5 doesn't have squawk or Emergency bit. Both have the Alert and IsOnGround bits though.

michelb
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Post by michelb » January 8th, 2009, 1:50 pm

Hi, I some new to this SBS output,

But in which MSG output can I find the aircraft registration related to the HEX form:

eg flight KLM1601 = aircraft PH-XXX


kind regards,

Michel

DaveReid
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Post by DaveReid » January 8th, 2009, 2:12 pm

michelb wrote:Hi, I some new to this SBS output,

But in which MSG output can I find the aircraft registration related to the HEX form:

eg flight KLM1601 = aircraft PH-XXX
The registration doesn't appear in any of the socket messages (unless it's also being used as the callsign).

Socket MSG messages only have data which comes direct from the aircraft, plus various counter values and timestamps.
Dave Reid
Reading, Berks
www.civilaircraftregisters.org/Mode_S_Resources

michelb
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Post by michelb » January 8th, 2009, 3:14 pm

DaveReid wrote:
michelb wrote:Hi, I some new to this SBS output,

But in which MSG output can I find the aircraft registration related to the HEX form:

eg flight KLM1601 = aircraft PH-XXX
The registration doesn't appear in any of the socket messages (unless it's also being used as the callsign).

Socket MSG messages only have data which comes direct from the aircraft, plus various counter values and timestamps.
but how does the basestation handles this then ?????

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bones
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Post by bones » January 8th, 2009, 4:37 pm

The Basestation database provides fields for all the aircraft details but it is up to the user to populate these manually - or use a lookup service like SBSPopulate.

Aircraft only transmit essential operational data. It is up to ground units (SBS or real radar systems) to provide the additional data they need. In real life we get the aircraft information from the flight plan.

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