GT02A protocol identification

Hello guys,

Excellent work!
I am trying to identify the protocol of a chinese clone of GT02A https://www.ebay.com/itm/GT02A-Car-GPS-Tracker-GSM-GPRS-SMS-Vehicle-Tracking-Device-Monitor-Locator/163818956052

Board is GT02_MT6261D_V2.3 and imei is like 35267XXXXXXXXXX

Visually it is like TK110 and it is configured by sms like this:

APN123456 ipn_address (for internet access)
adminip123456 server_address server_port (for setting tracking server address)
fix015s***n123456 (for tracking every 15″)

Here is a dump of tracking every 5" separated by 0xD 0xA (not dumped)

[03:00:52] Server started...
[03:01:27] Client 127.0.0.1 connected
[03:01:28] 78 78
[03:01:28] 01 03 52 67 21 00 62 78 19 01 02 D1 5A
[03:01:32] 78 78 13 44 06 04 00 01 00 FB 65
[03:01:34] 78 78 22 22 13 0C 10 01 00 2B C6 04 14 56 A3 02 8D 91 F0 00 14 00 00 CA 05 00 1B 00 01 E3 00 00 00 00 FC 29 7C
...
[03:20:02] 78 78 22 22 13 0C 10 01 14 03 C6 04 14 56 19 02 8D 91 66 00 14 00 00 CA 05 00 1B 00 01 E3 00 00 00 01 9F 3B 6E
[03:20:12] 78 78 13 44 06 04 00 01 01 A0 FF EB
[03:20:15] 78 78 22 22 13 0C 10 01 14
[03:20:15] C7 04 14 56 76 02 8D 91 41 00 14 00 00 CA 05 00 1B 00 01 E3 00 00 00 01 A1 3A 6D
[03:20:22] 78 78 22 22 13 0C 10 01 14 17 C7 04 14 56 8B 02 8D 91 45 00 14 00 00 CA 05 00 1B 00 01 E3 00 00 00 01 A2 03 9F
[03:20:32] 78 78 22 22 13 0C 10 01 14 21 C7 04 14 56 73 02 8D 91 57 00 14 00 00 CA 05 00 1B 00 01 E3 00 00 00 01 A3 8F 7C
[03:20:41] Exception :Unable to read beyond the end of the stream.
[03:20:41] Client disconnected

It's GT06 protocol, port 5023.

Thanks Anton, i will give it a try later :)

It works, thank you Anton!
I am trying for a .net c# implementation, so the main source code to examine is this https://github.com/traccar/traccar/blob/master/src/main/java/org/traccar/protocol/Gt06ProtocolDecoder.java ?
This device is branded also as Concox GT06N am i right?

Hi!
I have the same GPS tracker, GT02_MT6261D_V2.3.
When I enter the port 5023, nothing...
Could someone help me please ?

Hola buenas noches, soy Jonathan de Argentina, me gustaría recibir ayuda. Hace poco comencé este camino de los tracker GPS y necesitaria ayuda con el tcp de mi tracker que sale codificado y no puedo pasarlo a HEX y obtener la información.

Así se vé el reporte:
[redacted binary]

What's the problem converting it to HEX?

Al hacer la conversión, los datos no pueden traducirse en ASCII, no dan valores correctos.

It cannot be converted to ASCII because it's not text. That's why we use HEX. I still don't understand what the problem is.