4G_2G DTU Products Function
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2.3. SMS AT Command
The SMS AT command refers to sending [AT+] by SMS to query and set parameters.
2.4. Overview of the AT Instruction Set
The AT+ command can be input directly through a serial port debugger such as a Hyper
Terminal, or it can be programmed. As shown in the figure below, through the SecureCRT tool,
AT+H is a help command that lists all the instructions and instructions (some commands are not
implemented, which is subject to the description of this document).
Figure 31.
AT Instruction Set
2.4.1. Instruction Syntax Format
The AT+ instruction uses an ASCII-based command line. The format of the instruction is as
follows:
➢
Format Description
◼
< >
:
Indicates the part that must be included
◼
[ ]
:
Indicates an optional part
➢
Command Message
