CheckSum J16 response Login

Marcio Martins2 months ago

Hi,

I’m facing a connection issue between my server and the J16 device, which uses the GT06 protocol. The terminal is sending the login packet correctly, but it is not sending the location data, repeatedly sending the login packet instead. I noticed that it tries to send a location packet occasionally, but the connection is closed, and it restarts sending the login packet.

I’m using PHP to process the packets, but I’m not sure if the problem is related to the checksum verification.

Error log:

[2025-03-07 18:30:17] Data received (hex): 78 78 1F 12 19 03 07 0D 1B 30 C6 00 44 FB 17 04 BE C4 68 0A 18 70 02 D4 05 9D 6A 00 8B 13 00 0D 63 07 0D 0A
[2025-03-07 18:30:17] Invalid checksum. Expected: 63, Received: 7
[2025-03-07 18:30:17] Invalid packet received.
[2025-03-07 18:30:18] Data received (hex): 78 78 1F 12 19 03 07 11 18 1D C6 00 44 FD 24 04 BE CA 68 0A 19 0E 02 D4 05 9D 6A 00 8B 13 00 0E B3 D6 0D 0A
[2025-03-07 18:30:18] Invalid checksum. Expected: 1, Received: 214
[2025-03-07 18:30:18] Invalid packet received.
[2025-03-07 18:30:19] Data received (hex): 78 78 1F 12 19 03 07 11 18 3B C6 00 44 FB 56 04 BE CF 18 0B 19 24 02 D4 05 9D 6A 00 8B 13 00 0F C5 15 0D 0A
[2025-03-07 18:30:19] Invalid checksum. Expected: 109, Received: 21
[2025-03-07 18:30:19] Invalid packet received.
[2025-03-07 18:33:15] Data received (hex): 78 78 0A 13 01 06 04 00 01 00 10 64 1D 0D 0A
[2025-03-07 18:33:15] Invalid checksum. Expected: 186, Received: 29
[2025-03-07 18:33:15] Invalid packet received.
[2025-03-07 18:33:44] Data received (hex): 78 78 0A 13 01 06 04 00 01 00 11 75 94 0D 0A
[2025-03-07 18:33:44] Invalid checksum. Expected: 67, Received: 148
[2025-03-07 18:33:44] Invalid packet received.
[2025-03-07 18:34:17] Connection with 177.61.213.174 closed.

Can anyone help me understand what’s causing these errors? What might be wrong with the checksum verification or the packet transmission?

Anton Tananaev2 months ago

How is this related to Traccar server?

Marcio Martins2 months ago

No, I am using my server privately with API.

Anton Tananaev2 months ago

If it's not related to Traccar server, then you posted in the wrong forum. It should be in the "other" section.