max485-raspberry-nodejs v2.0.1

max485-raspberry-nodejs

A simple and reliable Modbus RTU library for Node.js using SerialPort and Raspberry Pi GPIO with MAX485 RS485 transceivers.

Installation

npm install max485-raspberry-nodejs

Usage

const ModbusRTU = require("max485-raspberry-nodejs");

const client = new ModbusRTU({ path: "/dev/ttyAMA0", baudRate: 9600, re_pin: 27, de_pin: 17 });

(async () => {
    await new Promise(resolve => setTimeout(resolve, 2000));

    await client.write(1, 1, 1);

    const value = await client.read(1, 1);
    console.log(`Register value: ${value}`);
})();

Features

•	Supports Modbus RTU communication over RS485
•	Handles TX/RX switching for MAX485 chips
•	Implements retry logic to handle timeouts and bad responses
•	CRC validation for error detection
•	Optimized for Raspberry Pi GPIO control

License

MIT