Quectel BG96, Руководство разработчика, Страница: 52 / 90

EMQ – publish a message to singletopic
Publish a message to the system
singlepubtopic
.
singlepubtopic
is a predefined topic for single-
subscription systems, where the host is not expected to register a publish topic with
+EMQPUBOPEN
.
The publish topic and QoS (
singlepubtopicqos
) are defined in the configuration file. For more
information, see the [MQTT] section, Using the Quectel BG96 module configuration file on page 62. The
index is not required.
Type Syntax Returned Result
Test
AT+EMQ=? OK
Read
AT+EMQ? OK
or
ERROR
Write
AT+EMQ=<pubdata>
where
<pubdata>
– is the published message. If
<pubdata>
is not contained within quotes,
it is sent as text with no modification. The
maximum payload length is 1000
characters. All characters must be printable.
If
"<pubdata>"
is contained within quotes,
it is handled as either ASCII-hex or text.
ETM handles
"<pubdata>"
as ASCII-hex if
it contains an even number of valid ASCII-
hex characters (
0
-
9
,
a
-
f
,
A
-
F
). ASCII-hex is
converted to binary for transmission.
ETM handles all other data as text. For text
messages,
\
(escape characters) are
removed.
OK
– command result
SEND OK
– subsequent URC that is sent
when publish occurs. This will not happen
immediately if ETM is offline.
or
ERROR
– check that
[MQTT]
singlepubtopic
is configured in the
configuration file. For more information,
see singlepubtopic on page 67.
Example:
AT+EMQ="{\"BatteryPower\": \"Low\"}"
OK
SEND OK
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Eseye-enabled Quectel BG96 module Developer Guide v1.8
MQTT telemetry AT commands