SimCom SIM7800 Series User Manual

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SIM7500_SIM7600_SIM7800 Series_MQTT_AT Command Manual 29 / 41
indicate the topic and payload have been transmitted completely.
Defined Values
<client_index>
A numeric parameter that identifies a client. The range of permitted
values is 0 to 1.
<topic_total_len>
The length of message topic received from MQTT server. The
range is from 1 to 1024 bytes.
<payload_total_len>
The length of message body received from MQTT server. The
range is from 1 to 10240 bytes.
<sub_topic_len>
The sub topic packet length, The sum of <sub_topic_len> is equal
to <topic_total_len>.
<sub_topic>
The sub topic content.
<sub_payload_len>
The sub message body
packet length, The sum of
<sub_payload_len> is equal to <payload_total_len>.
<sub_payload>
The sub message body content.
3 Example
Before all MQTT related operations, we should ensure the following:
a) ensure GPRS network is available:
AT+CSQ
+CSQ: 23,0
OK
AT+CREG?
+CREG: 0,1
OK
AT+CGREG?
+CGREG: 0,1
OK
b) PDP context Enable:

SimCom SIM7800 Series Specifications

General

Brand	SimCom
Model	SIM7800 Series
Category	Control Unit
Language	English