AT Command Set

This chapter describes how to use various AT commands.

• Basic AT Command Set
• Bluetooth® Low Energy AT Command Set
• Peripheral Driver AT Command Set
• Cloud Platform Integration Command Set
• HTTP AT Command Set
• MQTT AT Command Set
• SNTP AT Command Set
• TCP/IP AT Command Set
• Wi-Fi AT Command Set

We strongly recommend reading the following before using commands to learn basic AT command information.

AT Command Types

Generic AT commands fall into four types:

Type	Command Format	Description
Test Command	AT+<command name>=?	Query internal parameters and value ranges of a set command
Query Command	AT+<command name>?	Return current parameter values
Set Command	AT+<command name>=<…>	Set user-defined parameter values and execute the command
Execute Command	AT+<command name>	Execute a command without user-defined parameters

• Not every AT command supports all four types above.

• Command parameters currently support string and integer types only.

• Parameters inside angle brackets < > cannot be omitted.

• Parameters inside square brackets [ ] are optional; defaults apply when omitted. For example, when running AT+WJAP with certain parameters omitted:

  AT+WJAP="ssid","password"
  AT+WJAP="ssid","password","11:22:33:44:55:66"
  

• When omitted parameters are followed by parameters that must be specified, use , as a placeholder separator, for example:

  AT+CWJAP="ssid","password",,1
  

• Use double quotes for string parameters, for example:

  AT+CWSAP="ESP756290","21030826",1,4
  

• Special characters must be escaped, such as ,, ", \, etc.

  • \\: Escape backslash.

  • \,: Escape comma; commas used to separate parameters do not need escaping.

  • \": Escape double quote; double quotes enclosing string parameters do not need escaping.

  • \<any>: Escape the <any> character; use <any> alone without a backslash.

• Only special characters within AT commands need escaping; other contexts do not. For example, when the AT port prints > waiting for input data, that data does not need escaping.

  AT+WJAP="comma\,backslash\\ssid","1234567890"
  AT+MQTTPUB=0,"topic","\"{\"sensor\":012}\"",1,0
  

• The default baud rate for AT commands is 115200.

• Each AT command must not exceed 256 bytes in length.

• The maximum receive buffer size per AT command packet is 1024 bytes.

• AT commands end with a newline (CR-LF), so the serial tool should be set to “Newline mode”.

• See Response Error Codes for AT command error code definitions.