# MQTT client AT commands
Source: [https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html)
Table : MQTT client AT commands
| Command | Description |
| --- | --- |
| [AT+MQTTINIT](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html#Toc185621689) | Set MQTT session init configuration |
| [AT+MQTTCONN](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html#Toc184732455) | Query/set MQTT client connect session |
| [AT+MQTTSUB](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html#Toc184732456) | Subscribe to an MQTT topic. |
| [AT+MQTTPUB](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html#Toc184732457) | Publish an MQTT message |
| [AT+MQTTPUBRAW](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html#Toc184732458) | Publish a long MQTT message |
| [AT+MQTTUNSUB](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html#Toc184732459) | Unsubscribe from an MQTT topic |
| [AT+MQTTDISCONN](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html#Toc184732460) | Close an MQTT connection |
| [AT+MQTTDESTROY](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html#Toc184732461) | Destroy an MQTT session |
| [AT+MQTTMODE](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html#at_mqttmode) | Set MQTT receiving mode |
## AT+MQTTINIT
Source: [https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html)
This command sets the MQTT session init configuration
### Operation type
Set
### Syntax
| Command | Response |
| --- | --- |
| AT+MQTTINIT | +MQTTINIT=<session\_id>,<transport scheme>
OK |
| AT+MQTTINIT=<session\_id>,<transport scheme>,<"ca\_file">,<"cert\_file">,<"key\_file"> | +EVT:MQTT\_INITED:<session\_id>
OK |
### Defined values
- ``: MQTT session ID: `0`, `1`
- ``: Transport scheme: TCP or SSL
- `<"cert_file">`: The file path of the certificate
- `<"key_file">`: The file path of the private key
- `<"ca_file">`: The file path of the CA used by the client to verify the server
Note: See [AT+HTTPSSLCFG](https://docs.qualcomm.com/doc/80-Y8730-10/topic/http_client_at_commands.html#at_httpsslcfg) for how to flash certificate files.
## AT+MQTTCONN
Source: [https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html)
This command queries or sets the MQTT client connect session.
### Operation type
Query/Set/Execution
### Syntax
| Command | Response |
| --- | --- |
| AT+MQTTCONN | +MQTTCONN=<session\_id>,<"host">,<port>,<clientid>,<username>,<password>,<keepalive>,<clean session>
OK |
| AT+MQTTCONN? | +MQTTCONN:<session\_id>,<state>,<transport scheme>,<"host">,<port>
OK |
| AT+MQTTCONN=<session\_id>,<"host">,<port>,<clientid>, <username>,<password>,<keepalive>,<clean session> | +EVT:MQTT\_CONNECTED:<session\_id>,<transport scheme>,<"host">,<port>,<reconnect>
+EVT:MQTT\_DISCONNECTED:<session\_id>
+EVT:MQTT\_KEEPLIVETIMEOUT:<session\_id> |
### Defined values
- ``: MQTT session ID: `0`, `1`
- `<"host">`: The name of the host to be connected, can be URL path or IP address
- ``: The port number to connect
- ``: Client ID string for MQTT client
- ``: Username to be used to connect to the server
- ``: Password to be used to connect to the server
- ``: Keep-alive seconds, default: 60s
- ``: Whether to establish a new, clean session or resume a previous session, default: 0
- ``: MQTT connection state:
- `0`: MQTT\_INIT
- `1`: MQTT\_CONNECTED
- `2`: MQTT\_DISCONNECT
- `3`: MQTT\_FORCE\_DISCONNECT
- ``: Transport scheme: TCP or SSL
Note: SSL isn't supported yet. The default value is TCP.
- ``: Whether reconnect when MQTT runs, default: 1
## AT+MQTTSUB
Source: [https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html)
This command subscribes to an MQTT topic.
### Operation type
Query/Set/Execution
### Syntax
| Command | Response |
| --- | --- |
| AT+MQTTSUB | +MQTTSUB=<session\_id>,<"topic">,<qos\_level>
OK |
| AT+MQTTSUB=<session\_id>,<"topic">,<qos\_level>,<"message">,<retain> | +EVT:MQTT\_SUBSUC:<session\_id>,<"topic">
+EVT:MQTT\_SUBFAIL:<session\_id>,<"topic">
+EVT:MQTT\_SUBALREADY:<"topic">
+EVT:MQTT\_SUBRECV:<session\_id>,<"topic">,<len>,<message> |
| AT+MQTTSUB? | +MQTTSUB:<session\_id>,<state>,<"topic">,<qos\_level> |
Note: Each session allows a maximum of 10 subscribed topics.
### Defined values
- ``: MQTT session ID
- `<"topic">`: The MQTT topic to subscribe to
- ``: Quality-of-service level to use, range: 0–2, default: 0
- ``: Received payload length
- ``: Received payload string
- ``: MQTT connection state:
- `0`: MQTT\_INIT
- `1`: MQTT\_CONNECTED
- `2`: MQTT\_DISCONNECT
- `3`: MQTT\_FORCE\_DISCONNECT
## AT+MQTTPUB
Source: [https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html)
This command publishes an MQTT Messages in string.
### Operation type
Set/Execution
### Syntax
| Command | Response |
| --- | --- |
| AT+MQTTPUB | +MQTTPUB=<session\_id>,<"topic">,<qos\_level>,<"message">,<retain>
OK |
| AT+MQTTPUB=<session\_id>,<"topic">,<qos\_level>,<"message">,<retain> | +EVT:MQTT\_PUBSUC:<session\_id>,<len>,<transport scheme>,<"host">,<port>
+EVT:MQTT\_PUBFAIL:<session\_id>,<scheme>,<"host">,<port> |
### Defined values
- ``: MQTT session ID
- `<"topic">`: The MQTT topic to publish to
- ``: Quality-of-service level to use, range: 0–2, default: 0
- `<"message">`: Message string payload to send
- ``: Message should be retained, default 0.
- ``: The total data length to send
- ``: Transport scheme: TCP or SSL
Note: SSL isn't supported yet. The default value is TCP.
- `<"host">`: The name of the host to be connected, can be URL path or IP address
- ``: The port number to connect
## AT+MQTTPUBRAW
Source: [https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html)
This command publishes a long MQTT message.
### Operation type
Set/Execution
### Syntax
| Command | Response |
| --- | --- |
| AT+MQTTPUBRAW | +MQTTPUBRAW=<session\_id>,<"topic">,<length>,<qos\_level>,<retain> |
| AT+MQTTPUBRAW=<session\_id>,<"topic">,<length>,<qos\_level>,<retain> | In data mode,
|
### Defined values
- ``: MQTT session ID
- `<"topic">`: The MQTT topic to publish to
- ``: The length of message string to be sent in data mode. After this command, the device prints `>` and then enters data mode to send data. The device automatically exits the data mode when all the data is sent or receives the `+++` command.
- ``: Quality-of-service level to use, range: 0–2, default: 0
- ``: Message should be retained, default 0.
- ``: The total data length to send
- ``: Transport scheme: TCP or SSL
Note: SSL isn't supported yet. The default value is TCP.
- `<"host">`: The name of the host to be connected, can be URL path or IP address
- ``: The port number to connect
## AT+MQTTUNSUB
Source: [https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html)
This command unsubscribes from an MQTT topic.
### Operation type
Set/Execution
### Syntax
| Command | Response |
| --- | --- |
| AT+MQTTUNSUB | +MQTTUNSUB=<session\_id>,<"topic">
OK |
| AT+MQTTUNSUB=<session\_id>,<"topic"> | +EVT:MQTT\_UNSUBSUC:<session\_id>,<"topic">
+EVT:MQTT\_UNSUBFAIL:<session\_id>,<"topic"> |
### Defined values
- ``: MQTT session ID
- `<"topic">`: The MQTT topic to unsubscribe from
## AT+MQTTDISCONN
Source: [https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html)
This command closes an MQTT connection.
### Operation type
Set/Execution
### Syntax
| Command | Response |
| --- | --- |
| AT+MQTTDISCONN | +MQTTDISCONN=<session\_id>
OK |
| AT+MQTTDISCONN=<session\_id> | +EVT:MQTT\_DISCONNECTED:<session\_id> |
### Defined values
``: MQTT session ID
## AT+MQTTDESTROY
Source: [https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html)
This command destroys an MQTT session.
### Operation type
Set/Execution
### Syntax
| Command | Response |
| --- | --- |
| AT+MQTTDESTROY | +MQTTDESTROY=<session\_id>
OK |
| AT+MQTTDESTROY=<session\_id> | +EVT:MQTT\_DESTROYED:<session\_id> |
### Defined values
``: MQTT session ID
## AT+MQTTMODE
Source: [https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html](https://docs.qualcomm.com/doc/80-Y8730-10/topic/mqtt_client_at_commands.html)
This command sets MQTT receiving mode to hexadecimal/string mode.
### Operation type
Set/Execution
### Syntax
| Command | Response |
| --- | --- |
| AT+MQTTMODE | +MQTTMODE=<0|1: string|hex>
OK |
| AT+MQTTMODE =<0|1: string|hex> | OK
Note:
If the flag is set to 1, the format of `+EVT:MQTT_SUBRECV` will be changed to `+EVT:MQTT_SUBRECVHEX:,<"topic">,,` |
### Defined values
- ``: MQTT session ID
- `<"topic">`: The MQTT topic to subscribe to
- ``: Received payload length
- ``: Received hexadecimal payload
Last Published: Jun 03, 2026
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