AT Commands For MQTT(S)
| No | Command | Description |
| L1601 | AT+CMQTTSTART | Start MQTT service |
| L1602 | AT+CMQTTSTOP | STOP MQTT service |
| L1603 | AT+CMQTTACCQ | Acquire a client |
| L1604 | AT+CMQTTREL | Release a client |
| L1605 | AT+CMQTTSSLCFG | Set the SSL context |
| L1606 | AT+CMQTTWILLTOPIC | Input the will topic |
| L1607 | AT+CMQTTWILLMSG | Input the will message |
| L1608 | AT+CMQTTDISC | Disconnect from server |
| L1609 | AT+CMQTTCONNECT | Connect to MQTT server |
| L1610 | AT+CMQTTTOPIC | Input the publish message topic |
| L1611 | AT+CMQTTPAYLOAD | Input the publish message body |
| L1612 | AT+CMQTTPUB | Publish a message to server |
| L1613 | AT+CMQTTSUBTOPIC | Input a subscribe message topic |
| L1614 | AT+CMQTTSUB | Subscribe a message to server |
| L1615 | AT+CMQTTUNSUBTOPIC | Input a unsubscribe message topic |
| L1616 | AT+CMQTTUNSUB | Unsubscribe a message to server |
| L1617 | AT+CMQTTCFG | Configure the MQTT Context |
L1601 AT+CMQTTSTART Start MQTT Service
AT+CMQTTSTART is used to start MQTT service by activating PDP context.
You must execute this command before any other MQTT related operations.
| E) AT+CMQTTSTART |
OK +CMQTTSTART: <err> or +CMQTTSTART: <err> OK or ERROR +CMQTTSTART: <err> or +CMQTTSTART: <err> ERROR or ERROR |
| Maximum Response Time | 120000ms |
| <err> | The result code, please refer to the next page of MQTT err and unsolicited code |
| Example |
AT+CMQTTSTART OK +CMQTTSTART: 0 |
NOTE
It must be executed before any other MQTT related operations
L1602 AT+CMQTTSTOP Stop MQTT Service
AT+CMQTTSTOP is used to stop MQTT service.
| E) AT+CMQTTSTOP |
OK +CMQTTSTOP: <err> or +CMQTTSTOP: <err> OK or ERROR +CMQTTSTOP: <err> or +CMQTTSTOP: <err> ERROR or ERROR |
| <err> | The result code, please refer to the next page of MQTT err and unsolicited code |
| Example |
AT+CMQTTSTOP OK +CMQTTSTOP: 0 |
L1603 AT+CMQTTACCQ Acquire a Client
AT+CMQTTACCQ is used to acquire a MQTT client.
It must be called before all commands about MQTT connect and after AT+CMQTTSTART.
| T) AT+CMQTTACCQ=? |
+CMQTTACCQ: (0-1),(1-128),(0-1),(3-4) OK |
| R) AT+CMQTTACCQ? |
+CMQTTACCQ: <client_index>,<clientID>,<server_type> +CMQTTACCQ: <client_index>,<clientID>,<server_type> OK |
|
W) AT+CMQTTACCQ=<client_index>, <clientID>[,<server_type> [,<mqtt_version>]] |
OK or +CMQTTACCQ: <client_index>,<err> ERROR or ERROR |
| <client_index> |
A numeric parameter that identifies a client. The range of permitted values is 0 to 1. |
| <clientID> |
The UTF-encoded string. It specifies a unique identifier for the client. The string length is from 1 to 128 bytes. |
| <server_type> |
A numeric parameter that identifies the server type. The default value is 0. 0 MQTT server with TCP 1 MQTT server with SSL/TLS |
| <mqtt_version> |
A numeric parameter that identifies the MQTT protocol version. The permitted value is 3 or 4. 3 MQTT version 3.1 4 MQTT version 3.1.1 |
| <err> | The result code, please refer to the next page of MQTT err and unsolicited code |
| Example |
AT+CMQTTACCQ=0,”client test0″,0,4 OK |
NOTE
It must be called before all commands about MQTT connect and after AT+CMQTTSTART
L1604 AT+CMQTTREL Release a Client
AT+CMQTTREL is used to release a MQTT client. It must be called after AT+CMQTTDISC and before AT+CMQTTSTOP.
| T) AT+CMQTTREL=? |
+CMQTTREL: (0-1) OK |
| R) AT+CMQTTREL? | OK |
| W) AT+CMQTTREL=<client_index> |
OK or +CMQTTREL: <client_index>,<err> ERROR or ERROR |
| Maximum Response Time | 120000ms |
| <client_index> |
A numeric parameter that identifies a client. The range of permitted values is 0 to 1. |
| <err> | The result code, please refer to the next page of MQTT err and unsolicited code |
| Example |
AT+CMQTTREL=0 OK |
NOTE
It must be called after AT+CMQTTDISC and before AT+CMQTTSTOP
L1605 AT+CMQTTSSLCFG Set the SSL Context
AT+CMQTTSSLCFG is used to set the SSL context which to be used in the SSL connection when it will connect to a SSL/TLS MQTT server.
It must be called before AT+CMQTTCONNECT and after AT+CMQTTSTART.
The setting will be cleared after AT+CMQTTCONNECT failed or AT+CMQTTDISC.
Note: If you don’t set the SSL context by this command before connecting to server by AT+CMQTTCONNECT,
the CMQTTCONNECT operation will use the SSL context as same as index <session_id>
(the 1st parameter of AT+CMQTTCONNECT) when connecting to the server.
| T) AT+CMQTTSSLCFG=? |
+CMQTTSSLCFG: (0,1),(0-9) OK |
| R) AT+CMQTTSSLCFG? |
+CMQTTSSLCFG: <session_id>,[<ssl_ctx_index >] +CMQTTSSLCFG: <session_id>,[<ssl_ctx_index >] OK |
|
W) AT+CMQTTSSLCFG= <session_id>,<ssl_ctx_index> |
OK or ERROR |
| <session_id> |
A numeric parameter that identifies a client. The range of permitted values is 0 to 1. |
| <ssl_ctx_index> |
The SSL context ID which will be used in the SSL connection. Refer to the <ssl_ctx_index> of AT+CSSLCFG |
| Example |
AT+CMQTTSSLCFG=0,1 OK |
NOTE
If you don’t set the SSL context by this command before connecting to server by AT+CMQTTCONNECT,
the CMQTTCONNECT operation will use the SSL context
as same as index <session_id> (the 1st parameter of AT+ CMQTTCONNECT) when connecting to the server
L1606 AT+CMQTTWILLTOPIC Input/Set the Will Topic
AT+CMQTTWILLTOPIC is used to input the topic of will message.
| T) AT+CMQTTWILLTOPIC=? |
+CMQTTWILLTOPIC: (0-1),(1-1024) OK |
|
W) AT+CMQTTWILLTOPIC= <client_index>,<req_length> |
> <input data/topic here> OK or +CMQTTWILLTOPIC: <client_index>,<err> ERROR or ERROR |
| <client_index> |
A numeric parameter that identifies a client. The range of permitted values is 0 to 1. |
| <req_length> |
The length of input topic. The will topic should be UTF-encoded string. The range is from 1 to 1024 bytes. |
| <err> | The result code, please refer to the page of MQTT err and unsolicited code |
| Example |
AT+CMQTTWILLTOPIC=0,15 >simcomwilltopic OK |
L1607 AT+CMQTTWILLMSG Input/Set the Will Message
AT+CMQTTWILLMSG is used to input the message body of will message.
| T) AT+CMQTTWILLMSG=? |
+CMQTTWILLMSG: (0-1),(1-1024),(0-2) OK |
|
W) AT+CMQTTWILLMSG= <client_index>,<req_length> ,<qos> |
> <input data/message here> OK or +CMQTTWILLMSG: <client_index>,<err> ERROR or ERROR |
| <client_index> |
A numeric parameter that identifies a client. The range of permitted values is 0 to 1. |
| <req_length> |
The length of input data. The will message should be UTF-encoded string. The range is from 1 to 1024 bytes. |
| <qos> |
The qos value of the will message. The range is from 0 to 2. |
| <err> | The result code, please refer to next page of MQTT err and unsolicited code |
| Example |
AT+CMQTTWILLMSG=0,17,0 >simcomwillmessage OK |
L1608 AT+CMQTTDISC Disconnect From Server
AT+CMQTTDISC is used to disconnect from the server.
| T) AT+CMQTTDISC=? |
+CMQTTDISC: (0-1),(0,60-180) OK |
| R) AT+CMQTTDISC? |
+CMQTTDISC: 0,<disc_state> +CMQTTDISC: 1,<disc_state> OK |
| W) AT+CMQTTDISC=<client_index>,<timeout> |
OK +CMQTTDISC: <client_index>,<err> or +CMQTTDISC: <client_index>,<err> OK or +CMQTTDISC: <client_index>,<err> ERROR or ERROR |
| Maximum Response Time | 120000ms |
| <client_index> |
A numeric parameter that identifies a client. The range of permitted values is 0 to 1. |
| <timeout> |
The timeout value for disconnection. The unit is second. The range is 60s to 180s. The default value is 0s (not set the timeout value) |
| <disc_state> |
1 disconnection 0 connection |
| <err> | The result code, please refer to the next page of MQTT err and unsolicited code |
| Example |
AT+CMQTTDISC=0,120 OK +CMQTTDISC: 0,0 |
L1609 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.
| T) AT+CMQTTCONNECT=? |
+CMQTTCONNECT: (0-1),(9-256),(1-64800),(0-1) OK |
| R) AT+CMQTTCONNECT? |
+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 |
|
W) AT+CMQTTCONNECT=<client_index>, <server_addr>,<keepalive_time>, <clean_session>[,<user_name> [,<pass_word>]] |
OK +CMQTTCONNECT: <client_index>,<err> or +CMQTTCONNECT: <client_index>,<err> ERROR or ERROR |
| Maximum Response Time | 120000ms |
| <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 this “tcp://116.247.119.165:5141”, must begin with “tcp://”. If the <server_addr> not include the port, the default port is 1883. |
| <keepalive_time> |
The time interval between two messages received from a client. The client will send a keep-alive packet when there is no message sent to server after song long time. The range is from 1s to 64800s (18 hours) |
| <clean_session> |
The clean session flag. The value range is from 0 to 1, and default value is 0. 0 the server must store the subscriptions of the client after it disconnected. This includes continuing to store QoS 1 and QoS 2 messages for the subscribed topics so that they can be delivered when the client reconnects. The server must also maintain the state of in-flight messages being delivered at the point the connection is lost. This information must be kept until the client reconnects. 1 the server must discard any previously maintained information about the client and treat the connection as “clean”. The server must also discard any state when the client disconnects. |
| <user_name> |
The user name identifies the name of the user which can be used for authentication when connecting to server. The string length is from 1 to 256 bytes. |
| <password> |
The password corresponding to the user which can be used for authentication when connecting to server. The string length is from 1 to 256 bytes. |
| <err> | The result code, please refer to the page of MQTT err and unsolicited code |
| Example |
AT+CMQTTCONNECT=0,”tcp://hooleeping.com:8883″,60,1 OK +CMQTTCONNECT: 0,0 |
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+CMQTTCONNECT) SSL context when connecting to the server.
L1610 AT+CMQTTTOPIC Input The Publish Message Topic
| T) AT+CMQTTTOPIC=? |
+CMQTTTOPIC: (0-1),(1-1024) OK |
| W) AT+CMQTTTOPIC=<client_index>,<req_length> |
> <input data here> OK or +CMQTTTOPIC: <client_index>,<err> ERROR or ERROR |
| <client_index> |
A numeric parameter that identifies a client. The range of permitted values is 0 to 1. |
| <req_length> |
The length of input topic data. The publish message topic should be UTF-encoded string. The range is from 1 to 1024 bytes. |
| <err> | The result code, please refer to next page of MQTT err and unsolicited code |
| Example |
AT+CMQTTTOPIC=0,11 >simcomtopic OK |
NOTE
The topic will be clean after execute AT+CMQTTPUB
L1611 AT+CMQTTPAYLOAD Input The Publish Message Body
| T) AT+CMQTTPAYLOAD=? |
+CMQTTPAYLOAD: (0-1),(1-10240) OK |
| W) AT+CMQTTPAYLOAD=<client_index>,<req_length> |
> <input data here> OK +CMQTTPAYLOAD: <client_index>,<err> ERROR or ERROR |
| <client_index> |
A numeric parameter that identifies a client. The range of permitted values is 0 to 1. |
| <req_length> |
The length of input message data. The publish message should be UTF-encoded string. The range is from 1 to 10240 bytes |
| <err> | The result code, please refer to to next page of MQTT err and unsolicited code |
| Example |
AT+CMQTTPAYLOAD=0,13 >simcompayload OK |
NOTE
The payload will be clean after execute AT+CMQTTPUB
L1612 AT+CMQTTPUB Publish A Message To Server
| T) AT+CMQTTPUB=? |
+CMQTTPUB: (0-1),(0-2),(60-180),(0-1),(0-1) OK |
| W) AT+CMQTTPUB=<client_index>,<qos>,<pub_timeout>[,<ratained> [,<dup>]] |
OK +CMQTTPUB: <client_index>,<err> or +CMQTTPUB: <client_index>,<err> ERROR or ERROR |
| Maximum Response Time | 120000ms |
| <client_index> |
A numeric parameter that identifies a client. The range of permitted values is 0 to 1. |
| <qos> |
The publish message’s qos. The range is from 0 to 2. 0 at most once 1 at least once 2 exactly once |
| <pub_timeout> |
The publishing timeout interval value. Since the client publish a message to server, it will report failed if the client receive no response from server after the timeout value seconds. The range is from 60s to 180s |
| <ratained> |
The retain flag of the publish message. The value is 0 or 1. The default value is 0. When a client sends a PUBLISH to a server, if the retain flag is set to 1, the server should hold on to the message after it has been delivered to the current subscribers |
| <dup> |
The dup flag to the message. The value is 0 or 1. The default value is 0. The flag is set when the client or server attempts to re-deliver a message |
| <err> | The result code, please refer toto next page of MQTT err and unsolicited code |
| Example |
AT+CMQTTPUB=0,0,120 OK +CMQTTPUB: 0,0 |
L1613 AT+CMQTTSUBTOPIC Input a Subscribe Message Topic
| T) AT+CMQTTSUBTOPIC=? |
+CMQTTSUBTOPIC: (0-1),(1-1024),(0-2) OK |
|
W) AT+CMQTTSUBTOPIC= <client_index>,<req_length>,<qos> |
> <input data here> OK or +CMQTTSUBTOPIC: <client_index>,<err> ERROR or ERROR |
| <client_index> |
A numeric parameter that identifies a client. The range of permitted values is 0 to 1. |
| <req_length> |
The length of input topic data. The publish message topic should be UTF-encoded string. The range is from 1 to 1024 bytes. NOTE: The max length of the total cached topics is 5120 |
| <qos> |
The publish message’s qos. The range is from 0 to 2. 0 at most once 1 at least once 2 exactly once |
| <err> | The result code, please refer to next page of MQTT err and unsolicited code |
| Example |
AT+CMQTTSUBTOPIC=0,11,0 >simcomtopic OK |
NOTE
The topic will be clean after executing AT+CMQTTSUB.
L1614 AT+CMQTTSUB Subscribe a Message to Server
| T) AT+CMQTTSUB=? |
+CMQTTSUB: (0-1),(1-1024),(0-2),(0-1) OK |
|
Subscribe one or more topics which input by AT+CMQTTSUBTOPIC
W) AT+CMQTTSUB=<client_index> [,<dup>] |
OK +CMQTTSUB: <client_index>,<err> or +CMQTTSUB: <client_index>,<err> ERROR or ERROR |
|
Subscribe one topic W) AT+CMQTTSUB=<client_index>, <reqLength>,<qos>[,<dup>] |
> <input data here> OK +CMQTTSUB: <client_index>,<err> or +CMQTTSUB: <client_index>,<err> ERROR or ERROR |
| Maximum Response Time | 120000ms |
| <client_index> |
A numeric parameter that identifies a client. The range of permitted values is 0 to 1. |
| <req_length> |
The length of input topic data. The message topic should be UTF-encoded string. The range is from 1 to 1024 bytes. |
| <qos> |
The publish message’s qos. The range is from 0 to 2. 0 at most once 1 at least once 2 exactly once |
| <dup> |
The dup flag to the message. The value is 0 or 1. The default value is 0. The flag is set when the client or server attempts to re-deliver a message. |
| <err> | The result code, please refer to next page of MQTT err and unsolicited code |
| Example |
AT+CMQTTSUB=0 OK +CMQTTSUB: 0,0 |
L1615 AT+CMQTTUNSUBTOPIC Input a Unsubscribe Message Topic
| T) AT+CMQTTUNSUBTOPIC=? |
+CMQTTUNSUBTOPIC: (0-1),(1-1024) OK |
| W) AT+CMQTTUNSUBTOPIC=<client_index>,<req_length> |
> <input data here> OK or +CMQTTUNSUBTOPIC: <client_index>,<err> ERROR or ERROR |
| <client_index> |
A numeric parameter that identifies a client. The range of permitted values is 0 to 1. |
| <req_length> |
The length of input topic data. The publish message topic should be UTF-encoded string. The range is from 1 to 1024 bytes. |
| <err> | The result code, please refer to next page of MQTT err and unsolicited code |
| Example |
AT+CMQTTUNSUBTOPIC=0,11 >simcomtopic OK |
NOTE
The max length of the total cached topics is 5120.
The topic will be clean after execute AT+CMQTTUNSUB.
L1616 AT+CMQTTUNSUB Unsubscribe A Message To Server
| T) AT+CMQTTUNSUB=? |
+CMQTTUNSUB: (0-1),(1-1024),(0-1) OK |
|
Unsubscribe one or more topics which input by AT+CMQTTUNSUBTOPIC
W) AT+CMQTTUNSUB=<client_ index> ,<dup> |
OK +CMQTTUNSUB: <client_index>,<err> or +CMQTTUNSUB: <client_index>,<err>
ERROR or ERROR |
|
Unsubscribe one topic W) AT+CMQTTUNSUB=<client_ index> ,<reqLength>,<dup> |
> <input data here> OK +CMQTTUNSUB: <client_index>,<err> or +CMQTTUNSUB: <client_index>,<err> ERROR or ERROR |
| Maximum Response Time | 120000ms |
| <client_index> |
A numeric parameter that identifies a client. The range of permitted values is 0 to 1. |
| <req_length> |
The length of input topic data. The message topic should be UTF-encoded string. The range is from 1 to 1024 bytes. |
| <dup> |
The dup flag to the message. The value is 0 or 1. The default value is 0. The flag is set when the client or server attempts to re-deliver a message. |
| <err> | The result code, please refer to next page of MQTT err and unsolicited code |
| Example |
AT+CMQTTUNSUB =0,0 OK +CMQTTUNSUB: 0,0 |
L1617 AT+CMQTTCFG Configure The MQTT Context
| T) AT+CMQTTCFG=? |
+CMQTTCFG: “checkUTF8”,(0-1),(0-1) +CMQTTCFG: “optimeout”,(0-1),(20-120) OK |
| R) AT+CMQTTCFG? |
+CMQTTCFG: 0,<checkUTF8_flag>,<optimeout_val> +CMQTTCFG: 1,<checkUTF8_flag>,<optimeout_val> OK |
|
Configure the check UTF8 flag of the specified MQTT client context. W) AT+CMQTTCFG=”checkUTF8″, <client_index>,<checkUTF8_flag> |
OK or +CMQTTCFG: <client_index>,<err> OK or ERROR |
|
Configure the max timeout interval of the send or receive data operation W) AT+CMQTTCFG=”optimeout “, <client_index>,<optimeout_val> |
OK or +CMQTTCFG: <client_index>,<err> OK or ERROR |
| <client_index> |
A numeric parameter that identifies a client. The range of permitted values is 0 to 1. |
| <checkUTF8_flag> |
The flag to indicate whether to check the string is UTF8 coding or not, the default value is 1. 0 Not check UTF8 coding. 1 Check UTF8 coding. |
| <optimeout_val> |
The max timeout interval of sending or receiving data operation. The range is from 20 seconds to 120 seconds, the default value is 120 seconds. |
| <err> | The result code, please refer to next page of MQTT err and unsolicited code |
| Example |
AT+CMQTTCFG=”checkUTF8″,0,0 OK AT+CMQTTCFG=”optimeout”,0,120 OK |
NOTE
It must be called before AT+CMQTTCONNECT and after AT+CMQTTACCQ. The setting will be cleared after AT+CMQTTREL
WiFi IoT Module
Bluetooth Module
5G/LTE/CAT-M1/NB-IoT
