EDACS EA: Patch/regroup decoding

[ilyacodes]

Starting this issue to track RE and decoding of Extended Addressing MT1: 1F; MT2: C - aka "patching/regroup" based on current theories. (#199 is getting a bit unwieldy)

[lwvmobile]

Yeah, was looking at Site 177, definitely seeing some activity I didn't notice before, possibly because my bit shifts were wrong, but now I'm seeing some extra behavior like this, which correlates with some of your observations in the notes.

20:32:27 Sync: +EDACS  MSG_1 [FE70027] MSG_2 [6800262] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00039] Target [0000610] UNK1 [7] UNK2 [68]
20:32:27 Sync: +EDACS  MSG_1 [FE70027] MSG_2 [6800241] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00039] Target [0000577] UNK1 [7] UNK2 [68]
20:32:30 Sync: +EDACS  MSG_1 [FE70027] MSG_2 [6800262] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00039] Target [0000610] UNK1 [7] UNK2 [68]
20:32:30 Sync: +EDACS  MSG_1 [FE70027] MSG_2 [6800241] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00039] Target [0000577] UNK1 [7] UNK2 [68]
20:32:33 Sync: +EDACS  MSG_1 [FE70027] MSG_2 [6800262] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00039] Target [0000610] UNK1 [7] UNK2 [68]
20:32:34 Sync: +EDACS  MSG_1 [FE70027] MSG_2 [6800241] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00039] Target [0000577] UNK1 [7] UNK2 [68]
20:32:37 Sync: +EDACS  MSG_1 [FE70027] MSG_2 [6800262] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00039] Target [0000610] UNK1 [7] UNK2 [68]
20:32:37 Sync: +EDACS  MSG_1 [FE70027] MSG_2 [6800241] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00039] Target [0000577] UNK1 [7] UNK2 [68]
20:32:40 Sync: +EDACS  MSG_1 [FE70027] MSG_2 [6800262] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00039] Target [0000610] UNK1 [7] UNK2 [68]
20:32:40 Sync: +EDACS  MSG_1 [FE70027] MSG_2 [6800241] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00039] Target [0000577] UNK1 [7] UNK2 [68]
20:32:43 Sync: +EDACS  MSG_1 [FE70027] MSG_2 [6800262] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00039] Target [0000610] UNK1 [7] UNK2 [68]
20:32:43 Sync: +EDACS  MSG_1 [FE70027] MSG_2 [6800241] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00039] Target [0000577] UNK1 [7] UNK2 [68]
20:32:44 Sync: +EDACS  MSG_1 [FE00027] MSG_2 [FE00027] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00039] Target [0000039] UNK2 [FE]

20:30:41 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:30:42 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:30:44 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:30:44 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:30:47 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:30:47 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:30:50 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:30:50 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:30:53 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:30:53 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:30:55 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:30:55 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:30:58 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:30:58 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:01 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:01 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:04 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:04 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:06 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:06 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:09 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:09 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:12 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:12 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:15 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:15 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:17 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:17 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:20 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:20 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:23 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:23 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:26 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:26 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:28 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:29 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:31 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:31 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:34 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:34 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:37 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:37 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:39 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:40 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:42 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:42 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:45 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:45 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:48 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:48 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:51 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:51 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:53 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:53 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:56 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:56 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:31:59 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:31:59 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:32:02 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:32:02 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:32:04 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:32:05 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:32:07 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:32:07 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:32:10 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:32:10 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:32:13 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:32:13 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:32:15 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:32:16 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001154] UNK1 [7] UNK2 [48]
20:32:18 Sync: +EDACS  MSG_1 [FE70051] MSG_2 [4800483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0001155] UNK1 [7] UNK2 [48]
20:32:18 Sync: +EDACS  MSG_1 [FE00051] MSG_2 [FE00051] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID [00081] Target [0000081] UNK2 [FE]

Beginning to think the UNK1 is akin TGA again (Type, Group, Active) and it looks like when its deactivated, the target is the SGID itself. I originally thought UNK2 was SSN (could still be) but I thought I saw a non-unique value shared between two SGID values, but I'm wondering now if my leery eyes were playing tricks on me, or if with the code incorrect, I saw the FE value somewhere and decided it wasn't an SSN like number. Still just theories though.

[ilyacodes]

So I have a handful of questions:

1. What is the source of the knowledge you have so far? (SGID and target, for instance).
   • I agree that it seems believable, I'm just curious to understand how much we know vs speculate.
2. Have you validated the SGIDs and targets against UniTrunker or other software?
3. Have you tried or considered validating some of the data using a Harris radio (rx only, see if the patch works)?
4. Why do you believe the target can be a radio LID?
   • I'm somewhat struggling to imagine a patch that isn't using groups... unless they merged dynamic regroup in with patches, which would be a bit whack, but it is Harris.
5. Have you ever seen an SGID field > 255?

[lwvmobile]

1. What is the source of the knowledge you have so far? (SGID and target, for instance).

These values can be found on RR for Group Patches vs Individual Groups found in the patch.

22:51:12 Sync: +EDACS  MSG_1 [FE70056] MSG_2 [6000482] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID: 00086; Target: 0001154
22:51:12 Sync: +EDACS  MSG_1 [FE70056] MSG_2 [6000483] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID: 00086; Target: 0001155;
22:51:12 Sync: +EDACS  MSG_1 [FE70056] MSG_2 [6000463] (MT1: 1F; MT2: C)  System Dynamic Regroup :: SGID: 00086; Target: 0001123;

is listed on RR as

86  DE  FHP LakeCity    Patch Lake City Troop-B
1123    DE  FHP Lake Cit    Lake City Troop-B   Law Dispatch
1154    DE  FHP Lake Cit    Lake City Troop-B   Law Tac
1155    DE  FHP Lake Cit    Lake City Troop-B

Have you validated the SGIDs and targets against UniTrunker or other software?

Yes, this is how they were originally reverse engineered way back in the day before I even started working on DSD-FME. Unitrunker was used and it displayed these values.

Have you tried or considered validating some of the data using a Harris radio (rx only, see if the patch works)?

I do not have any radios, or ways to program them, so no, I cannot test this out with real hardware in any capacity. Also, I definitely do not with to get on some radar for attempting to do so.

Why do you believe the target can be a radio LID?

Because Harris has a documented method of doing so with P25, and I don't think its too much of a stretch to assume they can/do the same here, granted, that is only speculation. Its possible that they do not do so on EDACS EA. Again, see:

http://forums.radioreference.com/threads/duke-energy-p25-system.411183/post-3908078

My theory is that the ideas from older systems was borrowed or modified before being brought to P25 for compatibility/upgrade reasons. Why reinvent the wheel.

5. Have you ever seen an SGID field > 255?

I have not, so its quite possible / probable that this is only meant to be an 8-bit value as opposed to a 16-bit value (oversight).

[ilyacodes]

Thanks! That's all very useful to know.

A big part of the reason I ask [5] is because the SGID seemingly being <= 255 is interesting to me - and with the encrypted nature of SLERS, it's hard to know for sure that the RRDB [1] is indeed accurate. Of course with the dearth of EA systems still running, seeing UniTrunker also treats it this way [2] is definitely a as good a vote in favour as we are going to get (though data from other systems would be fantastic).

I'll have to take some time to read up on the Harris P25 group/regroup commands [4] and how they work. I think you're onto something that it may have been inspired by whatever they did on EA.

[lwvmobile]

I'm honestly not sure how they come to who is what group when they are virtually 99% encrypted, I can only assume that at one point they were not encrypted and thus these values were obtainable, or they were also on an older analog system and had simultaneous traffic on A and B.

Another thing that got me going down the P25 Harris Documentation, is the Dynamic Regroup Bitmap, which is just a bunch of FFFF values, all bits activated. I also see this often on Harris P25 in the form of this undocumented PDU, which got me going down the path of looking at the fact they may be recycling old ideas into newer systems.

23:05:45        P25p2 LCCH   MAC_SIGNAL 
 MFID A4 (Harris); Res: 0; Len: 18; Opcode: 01; 0F110DFFFFFFFFFFFFFFFFFFFFFFFF
 P25 PDU Payload
  [1C][81][A4][12][0F][11][0D][FF][FF][FF][FF][FF]
  [FF][FF][FF][FF][FF][FF][FF][01][A3][62][E0][00]

[lwvmobile]

Also, here is something random but maybe of interest when looking for clues.

https://www.l3harris.com/all-capabilities/edacs-migration-gateway

Integration with Existing EDACS System

The EDACS Migration Gateway (EMG) integrates call services between your new L3Harris system and your existing EDACS system. Users and dispatchers can communicate across the systems with call features no other vendor can offer—including Caller ID, Patch, Simulselect, Individual Call, Console Pre-empt, Emergency Calls and Request To Talk. Whether migrating your field users or dispatchers first, the EMG offers this level of functionality throughout the transition.