4G_2G DTU Products Function
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Figure 17.
Transparent Transmission Mode Registration Packet Function Transmission
The example of registration package function is as follows: The following commands respectively
enable the registration function of Socket A, set the content of the registration package to version
signal st ABCD, enable the registration package when establishing connection and
sending data.
Figure 18.
Transparent Transmission Mode Registration Package Function Example
1.4. Heartbeat Package Function
In the transparent transmission mode, the heartbeat packet function can be enabled, and the
module periodically sends heartbeat data to the server or the serial port. For details, refer to the
AT+HEART command. The main purpose of sending to the network is to keep the connection with the
server, and to make the connection status valid for modules that are idle for a long time (the data will
not be sent to the server for a long time). When the connection is abnormal, the module detects that
the heartbeat packet data cannot be sent to the server. If the number of failed transmissions is greater
than 3, the module considers that the connection is abnormal and will try to reconnect to the server.
In an application where the server sends a fixed query command to the device, in order to reduce
the communication traffic, the user can choose to send a heartbeat packet (query command) to the
serial device to replace the sending of the query command from the server.
