RS485 Control Tutorial

RS485 Control

Connect the ESP32-S3-ETH-8DI-8RO device using RS485, and send data to ESP32-S3-ETH-8DI-8RO to control the opening and closing of each relay. Communication is performed at a default baud rate of 9600.

Operation Command	Command Function
06 05 00 01 55 00 A2 ED	Switch the state of CH1 relay
06 05 00 02 55 00 52 ED	Switch the state of CH2 relay
06 05 00 03 55 00 03 2D	Switch the state of CH3 relay
06 05 00 04 55 00 B2 EC	Switch the state of CH4 relay
06 05 00 05 55 00 E3 2C	Switch the state of CH5 relay
06 05 00 06 55 00 13 2C	Switch the state of CH6 relay
06 05 00 07 55 00 42 EC	Switch the state of CH7 relay
06 05 00 08 55 00 72 EF	Switch the state of CH8 relay
06 05 00 FF FF 00 BD BD	Turn on all relays
06 05 00 FF 00 00 FC 4D	Turn off all relays

Hardware Connection

Here we use the example of USB TO RS232/485 Converter for demonstration

ESP32-S3-Relay-6CH	USB-TO-RS232-485
RS485 - A+	Tx B - A+
RS485 - B-	Rx B - B-

Software Operation

Use SSCOM to send data
Open the SSCOM software and select the COM port corresponding to the Port B connected above
Open the serial port and use the Send Multi Char function to quickly send commands

You can control the relays with the following commands

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