SimCom SIM7800 Series User Manual

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SIM7500_SIM7600_SIM7800 Series_MQTT_AT Command Manual 16 / 41
2.2.8 AT+CMQTTCONNECT Connect to MQTT server
AT+CMQTTCONNECT is used to connect to a MQTT server.
NOTE: If you don’t set the SSL context by AT+CMQTTSSLCFG before connecting a SSL/TLS MQTT server by
AT+CMQTTCONNECT, it will use the <client_index> (the 1st parameter of AT+CMQTTCONNNECT) SSL
context when connecting to the server.
AT+CMQTTCONNECT Connect to MQTT server
Test Command
AT+CMQTTCONNECT=?
Response
+CMQTTCONNECT: (0-1),(9-256),(60-64800),(0-1)
OK
Read Command
AT+CMQTTCONNECT?
Response
+CMQTTCONNECT:
0[,<server_addr>,<keepalive_time>,<clean_session>[,<user_
name>[,<pass_word>]]]
+CMQTTCONNECT:
1[,<server_addr>,<keepalive_time>,<clean_session>[,<user_
name>[,<pass_word>]]]
OK
Write Command
AT+CMQTTCONNECT=<client_index>,
<server_addr>,<keepalive_time>,<clean_
session>[,<user_name>[,<pass_word>]]
Response
a)If successfully:
OK
+CMQTTCONNECT: <client_index>,0
b)If failed:
OK
+CMQTTCONNECT: <client_index>,<err>
c)If failed:
+CMQTTCONNECT: <client_index>,<err>
ERROR
d)If failed:
ERROR
Defined Values
<client_index>
A
numeric parameter that identifies a client. The range of
permitted values is 0 to 1.
<server_addr>
The string that described the server address and port. The range
of the string length is 9 to 256 bytes. The string should be like

SimCom SIM7800 Series Specifications

General

Brand	SimCom
Model	SIM7800 Series
Category	Control Unit
Language	English

Summary

Introduction to MQTT AT Commands

1.1 SSL Context Management for SSL/TLS MQTT

Explains AT commands for managing SSL context for MQTT.

1.2 Process of Using MQTT AT Commands

Outlines the steps for using MQTT AT commands in sequence.

MQTT AT Command Reference

2.1 SSL Context Management AT Commands

Details AT commands for configuring SSL contexts for secure MQTT connections.

2.2 MQTT Services AT Commands

Covers AT commands for starting, stopping, and managing MQTT client services.

2.3 Command Result and Unsolicited Codes

Lists all command result codes and unsolicited codes for MQTT operations.

MQTT Usage Examples

3.1 Access MQTT Server (Not SSL/TLS)

Demonstrates connecting to an MQTT server without SSL/TLS.

3.2 Connect to SSL/TLS MQTT Server (No Server Verification)

Shows connecting to SSL/TLS MQTT server without verifying the server.

3.3 Access SSL/TLS MQTT Server (Verify Server Only)

Details accessing SSL/TLS MQTT server with server verification.

3.4 Access SSL/TLS MQTT Server (Verify Server and Client)

Illustrates connecting to SSL/TLS MQTT server with both server and client verification.

3.5 Access MQTT Server without UTF8 Coding Check

Explains communication with MQTT server without UTF8 coding check.