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4.6.3.3 Query ADC
To read ADC status(current input)
Request: 01 04 00 02 00 01 90 0A
Response:01 04 02 00 64 B8 DB
Notes of the modbus commands. Take the command 01 04 00 01 00 01 60 0A for
example.
Response 01 04 02 00 B8 B9 42
The acquisition value in HEX. You need to convert it to DEC and calculate with
the formula below:
Current type: 3.3/1023 *acquisition value/150 *1000= (mA)
Voltage type: 3.3/1023 *acquisition value/12.1*20.16=
（
V
）
(The acquisition value should be converted to DEC)
4.7 MQTT Test
Modem can work as MQTT client.you need set work mode in MQTT,Client ID can
be configured to the required string,username and password are from the MQTT
server (some servers dont need). Receive topic is the Send topic in another
MQTT client, Send topic is the Receive topic in another MQTT client,as shown in
the figure: