Overview; Json Simple Example; Modbus Rtu To Json; Modbus Table - Waveshare RS485 TO ETH Manual

485 TO ETH (B) User Manual

1. OVERVIEW

MQTT and JSON can be used alone or together. Among them, JSON supports Modbus
convert RTU format to JSON format.
The Main FEATURES:
1. Use the MQTT-based protocol to establish a connection with the server, and use the form
of subscription to publish data communication.
2. Support independent design and automatic collection of Modbus RTU registers.
3. Support the conversion of specific Modbus register content into JSON format and send it
regularly and actively.
4. Support adding device ID, time, and any string in JSON format.
5. Support nested writing method in JSON format.
6. Support NTP protocol, get the time automatically.
7. Support unsigned data and signed data, support decimal point representation, and
support 4-byte length data.
8. All configurations can be completed in interface configuration, and the user's independent
configuration does not need to be customized.
9. In addition to choosing MQTT, the protocol can support HTTP POST and GET methods.

2. JSON SIMPLE EXAMPLE

2.1. MODBUS RTU TO JSON

Modbus RTU to JSON can realize automatic collection of Modbus RTU tables, and
follow
The JSON format is automatically uploaded to the cloud server.
Here we explain this usage through a specific case.

2.2. MODBUS TABLE

Suppose there is a Modbus table with a function code of 3 and an address of 1. Its
register addresses and parameter names are as follows. Where the byte length is 4, it means
that 2 registers need to be read continuously.
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