Understanding Connect Plus trunking - Page 7

IanWraith · #**121** (**permalink**) 12-06-2012, 7:01 AM

Hello All

I have just uploaded DMRDecode build 57 to the usual place ..

https://github.com/IanWraith/DMRDecode/downloads

Note that from this build onwards you will need to have Java 7 installed to run the program. To find out which version you have installed go to a command prompt and type "java -version" if you don't see something like "java version 1.7.0" or the program doesn't run then you need to upgrade. The upgrade can be downloaded from here ..

Oracle Java Runtime Environment 7u9 Downloads

Build 57 should decode the Connect Plus CSBKO 01 FID=6 PDUs but I can't test this so would be grateful if one of you could. Also what other changes are needed ?

The code changes can be seen here ..

https://github.com/IanWraith/DMRDeco...CSBK.java#L231

Regards

Ian

inigo88 · #**122** (**permalink**) 12-06-2012, 4:37 PM

Just spotted another unknown one: CSBK=10. It's in my screenshot in the DMRDecode thread.

W8EMX · #**123** (**permalink**) 02-04-2013, 9:40 PM

After much studying of a local ConnectPlus system here, I determined that the next bit after the LCN group was a flag to indicate the timeslot on which the grant was issued (Motorola specifies in their documentation that the transmitted information to the subscriber includes repeater number AND timeslot informaiton)

A 0 in this field indicates Timeslot 1 and a "1" indicates Timeslot 2

I.E.

Code:

            Source                Group           LCN  TS
000000000000010001101010 000000000010001101000110 0100 0  00000000010  (Channel Grant : LCN 4  TS 1 Source 1130 Group 9030)
000000000000010001101010 000000000010001101000110 0100 1  00000000010  (Channel Grant : LCN 4  TS 2 Source 1130 Group 9030)
000000000000010001101010 000000000010001101000110 0101 0  00000000010  (Channel Grant : LCN 5  TS 1 Source 1130 Group 9030)
000000000000010001101010 000000000010001101000110 0101 1  00000000010  (Channel Grant : LCN 5  TS 2 Source 1130 Group 9030)

I made a few tweaks in my copy of the code to implement this and things chime along quite nicely, with each successive talkgroup walking up the LCN / TS step, just like most other Motorola trunking systems out there.

-_TS

Forts · #**124** (**permalink**) 02-04-2013, 9:45 PM

Nicely done, thanks for sharing that!!

IanWraith · #**125** (**permalink**) 02-05-2013, 2:45 AM

Hello
Many thanks for that information W8EMX. This has been incorporated into DMRDecode and a new build (59) is now ready for download ..

DMRDecode Download

I haven't been able to test this new feature so I would be grateful if someone could let me know it works OK.

The source code changes can be seen here along with the credits for who found this ..

https://github.com/IanWraith/DMRDeco...32b5da3c7e73b3

Thanks again.

Ian

inigo88 · #**126** (**permalink**) 02-08-2013, 6:40 AM

Awesome job guys! Can't wait to test it out!

ericcarlson · #**127** (**permalink**) 04-07-2013, 9:21 PM

I'm monitoring a new Connect Plus system in Houston. I'm seeing the CSBKO=18 and CSBKO=17 periodically on an otherwise idle system. Screenshot below.

radioprescott · #**128** (**permalink**) 04-09-2013, 10:13 PM

Is the network ID unique to a system or can it be reused in another state/region.

The reason I ask is that inigo88 reports Network 119 as a Fisher system in San Diego. I have a system here that reports:

Connect Plus Control Channel SLCO=10 Network: 119 Site: 72
Control Channel Neighbour List : 6,9,10,17,19 (0100011001001001010010100101000101010011000000000 000000000000111)

The CC alternates between 461.8125 and 462.5250, but both freqs are licensed to Niles Radio on Squaw Peak near Camp Verde, AZ, not Fisher (The only actvity on the Fisher licensed freqs at that location are LTR and Passport systems).

I have not seen any voice grants on this system in a week of daytime montoring, (I work at home and left DMR Decode running all day), and no activity noted on the other licensed freqs for Niles at that site.

IanWraith · #**129** (**permalink**) 04-10-2013, 12:55 AM

Hello John

Its most likely that the network ID can be set by who ever sets up the system so this type of ID is rarely unique. I'm not sure about the FCC on your side of the Atlantic but here in Britain their equivalent OFCOM has no interest in this type of identifier at all.

Regards

Ian

radioprescott · #**130** (**permalink**) 04-10-2013, 1:14 AM

Quote:

Originally Posted by IanWraith

Hello John

Its most likely that the network ID can be set by who ever sets up the system so this type of ID is rarely unique. I'm not sure about the FCC on your side of the Atlantic but here in Britain their equivalent OFCOM has no interest in this type of identifier at all.

Regards

Ian

Thanks Ian.

inigo88 · #**131** (**permalink**) 05-09-2013, 2:53 AM

Quote:

Originally Posted by radioprescott

Thanks Ian.

Hey John, I've been told the Capacity Plus Network ID is set by Motorola at the factory and can't be changed once it gets to the system admins. I could be mistaken though. I believe Forts would have more info. However if my recollection is correct, that would make the network ID more arbitrary and less unique. i.e. How many P25 conventional systems use NAC $293, simply because they have no desire to change it from the default. 119 may be a default network ID unless the subscriber requests otherwise. I've run across numerous Fisher systems around California and all are programmed with it.

MikeOxlong · #**132** (**permalink**) 05-09-2013, 6:10 AM

I think you're talking about Connect Plus not Capacity Plus. I've never seen a Capacity Plus system with a network ID.

From what I understand, the network ID is set by Motorola.

If you're seeing Network ID's on the Fisher system, than its Connect Plus and it makes sense that they all share the same ID.

Forts · #**133** (**permalink**) 05-09-2013, 8:19 AM

Quote:

Originally Posted by radioprescott

The reason I ask is that inigo88 reports Network 119 as a Fisher system in San Diego. I have a system that reports:

Connect Plus Control Channel SLCO=10 Network: 119 Site: 72
Control Channel Neighbour List : 6,9,10,17,19 (0100011001001001010010100101000101010011000000000 000000000000111)

Something seems odd there... Last I saw Connect Plus only supported 35 sites...

inigo88 · #**134** (**permalink**) 05-09-2013, 5:51 PM

Yeah sorry, I'm referring to Connect Plus. (At least I got the thread right.

) Capacity Plus has no network ID that I'm aware of... Forts is right about the number of sites. Unless the Connect Plus firmware was upgraded recently?

Frozentech · #**135** (**permalink**) 05-11-2013, 5:54 PM

Quote:

Originally Posted by inigo88

Yeah sorry, I'm referring to Connect Plus. (At least I got the thread right.

) Capacity Plus has no network ID that I'm aware of... Forts is right about the number of sites. Unless the Connect Plus firmware was upgraded recently?

The latest ConnectPlus firmware (R1.3) is still 35 sites, 30 timeslots per site max.