MQTT Configuration From Server Command :

To test communication with hardware
Send : 
{"method":"test"}
Response : 
{"response":"ok"}

Write multiple data to device using modbus function code 16
you can write any quantity as per slave device support
Send :
          {"method":"fn16", "params":"modbus id, fn code, start add, qty,data 1, data 2, data 3"}
Example : {"method":"fn16", "params":"1        , 16     , 0        , 3  ,     1,      2,      3"}
Response :
{"response":"fn16 ok"}

Read data from modbus slave device

Command Description
{"method":"txn", "params":"txn no, txn flag, modbus id, function code, start add , qty, poll interval, txn timeout, txn retry count"}

txn no          = number of slave device configuration supported in hardware
txn flag        = enable = 1 / disable = 0
modbus id       = slave device id
function code   = 3 or 4
start add       = start address
qty             = number of register read from device
poll interval   = delay between two command
txn timeout     = slave device response timeout
txn retry count = if response not receive, retry count

Send :
Example : {"method":"txn", "params":"0,1,1,3,0,10,1000,1000,1"}

Response :
{"response":"txn ok"}

sync time from internet server
Send :
{"method":"time sync"}
Response :
{"response":"time sync ok"}

comport setting
Send :
{"method":"comport", "params":"baud rate, config"}
{"method":"comport", "params":"9600     , 3     "}

Response :
{"response":"comport ok"}

LAN Card, MQTT Configuration Parameter :

Firmware Version
%{,??,INFO,}!

Set MQTT Server
%{,??,MQTTSERVER,server ip,}!

Set MQTT User
%{,??,MQTTUSER,user name,}!

Set MQTT Password
%{,??,MQTTPASS,password,}!

Set MQTT Subscriber Topic
%{,??,MQTTTOPICSUB,subscriber-topic,}!

Set MQTT Publish Topic
%{,??,MQTTTOPICPUB,publish-topic,}!

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