Four-Faith Modem(Dtu) UDP Data Format Document

Four-Faith Modem(Dtu) UDP Data Format Document

DTU UDP mode’s work process：

After DTU repowered, it will dail up automatic，after sucessful，it will send register packet to server. When register is successful, the data can be transmitted between the DTU and server.

Data format (DTU send to DSC）：

1．  Register packet

   

Start flag	Packet style	Packet length	DTU ID	DTU IP address	DTU port	Finish flag
1 byte	1 byte	2 bytes	11 bytes	4 bytes	2 bytes	1 byte
0x7b	0x01	0x16				0x7b

Note：

        DTU ID：  DTU RUIM card’s phone number，such as：13312345678

        DTU IP address   ：  IP Address which was assigned when DTU    PPP dail-up sucessful。

        DTU port  ：  DTU local port。

2．Data packet

      

Start flag	Packet style	Packet length	DTU ID	Finish flag	data
1 byte	1 byte	2 bytes	11 bytes	1 byte	Less 1024 bytes
0x7b	0x09	0x10		0x7b

The packet DSC send DTU：

1．  The response packet to DTU:

Start flag	Packet style	Packet length	DTU  ID	Finish flag
1 byte	1 byte	2 bytes	11 bytes	1 byte
0x7b	0x81	0x10		0x7b

2．The data packet  which DSC send to DTU：

  

Start flag	Packet style	Packet length	DTU ID	Finish flag	Data packet
1 byte	1 byte	2 bytes	11 bytes	1 byte	Less 1024 bytes
0x7b	0x89	0x10		0x7b

2．  Logout packet which DSC send to DTU:

  

Start flag	Packet style	Packet length	DTU ID	Finish flag
1 byte	1 byte	2 bytes	11 bytes	1 byte
0x7b	0x82	0x10		0x7b

Pls check below info for more details:
Xiamen Four-Faith Communication Technology Co., Ltd. is one of the professional wireless data communication terminal manufacturers in China. 
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