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Double Socket Transpond Test of USR-G781

Double Socket Transpond Test of USR-G781


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Double Socket Transpond


1. Connection diagram 

Your control devices(LOCATIONB)->(LAN)G781->(4G)->PC(LOCATIONB)

Connection diagram 


In this project , we need establish two socket to realize your requirement.

Note: there is a special function in G781 which name is DOUBLE SOCKET TRANSPOND


Your device (TCP server )->(LAN port)G781(TCP client)                            (location A )



   G781(TCP client)->PC(TCP server )                                  (location B )


At last:    

You device-> G781->PC


2. Before your test 

2.1 Please log on this link:

And down load the Utility [USR-G781] Setup Software V1.0.0.0

2.2 Make sure your location B ‘s PC’S IP address is public network ip address .

2.3 Your device controller can  built TCP connection with G781

2.4 The PC in location B has software that can built TCP connection with G781.


3. Hardware connection

Hardware connection

Note: RS 232 converter USB

RS 232 converter USB


4. Utility configurations

Open this software after download in your PC

Utility configurations


G781 factory default serial port parameter: baud rate 115200, check/data/stop: NONE/8/1.

Open the serial port as shown in the figure below

Open the serial port


Click to enter the configuration state. If you print +++ a a OK as shown in the figure below, then you enter the configuration state correctly. If the print information as shown in the figure below is not displayed, possible reasons:

1.The serial port number selected is not consistent with the serial port number of the computer connected to the device
2. No serial driver
3. The baud rate is not consistent with the actual baud rate of the device (if you have set the baud rate before and forget what the modified baud rate is, you can restore the factory setting and use the factory default parameters)
4. Hardware problems. Try replacing a serial cable


4.1 Set parameters

Working mode: transparent transmissions mode, server A address and destination port are set to A remote server, such as, 7118. 
The address of server B is the device IP and port. Such as and 2317

 Set parameters


4.2 Enable double socket

Serial port sending instructions:



Turn on the double-socket transmissions function (AT instruction should end with carriage return newline)

Enable double socket


4.3 Restart the device

After enabled the double socket function  please  save parameter and restart

Restart the device

NOTICE: AT  command is followed by a carriage return and newline

Set and save all parameters, and restart, wait for the serial port to print the start information usr-g781, indicating that the start is complete, then open the computer port monitoring, G781's link A and link B indicator lights will light up, indicating that the two socket successfully established and connected

G781's link A and link B indicator lights will light up


4. 4 Data transmissions

After the setup is complete, you can see the device connection on the server as follows. You can test the two-way data communication to indicate that the test is OK.