This is a modified version of the utility "tcpdump" / "windump",
a special development for the DMR-Monitor.
The modification creates a filtered output of the DMR header on the IP-side of a Motorola MotoTrbo network.
A new option for the type-parameter -T has been added: "-Tdmr".
Example call:
windump -x -l -n -Tdmr -i 1 udp portrange 50000-50005 and host 192.168.1.1
- Replace the device-ID (parameter -i) with the appropriate device ID for your system ("windump -D" shows a list)
- Replace the portrange by the range that you use on your DMR CBridge or SmartPTT for the different DMR networks.
- Replace the host-IP by the IP of your CBridge/SmartPTT server.
(Please find more information in the windump/tcpdump documentation)
Make sure that the limitation to a specific IP and a portrange is set up properly,
otherwise the tool may create a lot of useless traffic!
Output format:
After a short time of silence the tool will output 2 different record types.
Short record format:
2012-01-16 11:30:38 50002 98 310401 69
2012-01-16 11:30:39 50004 97315100 69
2012-01-16 11:30:39 50002 98 302700 69
2012-01-16 11:30:45 50000 98 262420 66
2012-01-16 11:30:47 50005 96 31081 69
2012-01-16 11:30:48 50002 98 311707 6a
2012-01-16 11:30:48 50001 98 232101 66
2012-01-16 11:30:49 50004 98 315101 69
2012-01-16 11:30:56 50004 98 312601 6a
2012-01-16 11:30:56 50000 99 262600 6a
2012-01-16 11:30:56 50000 97 262450 6a
2012-01-16 11:30:57 50004 98 312600 6a
2012-01-16 11:31:00 50000 98 262460 66
This records show the active repeaters on the network(s).
Each repeater-id will appear once per minute.
This is filtered to reduce traffic, the real frequence is 10 messages per minute from each repeater to each other
on the network and a reply back on each message.
The format shows 6 fields delimited by a single space character:
| 2012-01-16 | date |
| 11:31:00 | time in UTC |
| 50000 | UDP port where report came in (decimal), associated to a specific DMR network |
| 98 | format type-ID in hex (96 / 97 master-keep-alive and 98 / 99 slave-keep-alive request and response) |
| 262460 | repeater-ID in decimal (human readable) |
| 66 | connection status of timeslots in hex |
Long record format:
2012-06-30 14:19:28 50000 80 262406 209 3106113 1 02 00007ea2 00 80 dd 53072 71881140 0 01 40 11 84 0a 96
2012-06-30 14:19:31 50000 80 262406 209 3106113 1 02 00007ea2 40 80 5e 53122 71886f00 0 02 40 11 84 0a 96
2012-06-30 14:25:38 50050 80 232101 43 2323111 1 02 00003483 00 80 dd 16612 4ddc42c3 0 01 40 11 84 0a 96
2012-06-30 14:25:39 50050 80 232101 43 2323111 1 02 00003483 40 80 5e 16630 4ddc6483 0 02 40 10 80 0a 96
The record shows 22 fields which are delimited by a single space:
| 2012-06-30 | date |
| 14:19:28 | time in UTC |
| 50000 | UDP port where repeater reported (decimal) |
| 80 | format type-ID in hex (filtered for 80/81/84) |
| 262406 | repeater-ID in decimal (human readable) |
| 209 | sequence number of transmission in decimal, 0-255 (human readable) |
| 3106113 | source-ID in decimal (human readable) |
| 1 | destination-ID in decimal (human readable) |
| 02 | o12 (hex) |
| 00007ea2 | flctrl |
| 00 | o17 (hex) |
| 80 | o18 (hex) |
| dd | o19 (hex) |
| 53072 | sequence in decimal |
| 71881140 | tstmp in decimal |
| 0 | s |
| 01 | o30 |
| 40 | o31 |
| 11 | length |
| 84 | o34 |
| 0a | o35 |
| 96 | dz |
More details on the protocol can be found at dmr.darc.de
Select the button "log", then click on flags in the last column of a line in the log table.
This will open a new window which shows the decoding of the header of the selected transmission.
All standard features of windump/tcpdump have not been touched. Please check the manpage for more details.
Downloads:
Executable for Windows (WinPcap required) and samples of start scripts.Please check tcpdump.org for more information, documentation and requirements.
Patches for own compilation (Windows and Linux) based on windump/tcpdump rev. 3.9.3
Last update: 2012-06-30 - Hans-J. Barthen, DL5DI