Modbus RTU Master Library tests with Arduino Part 1 – PDAControl
Modbus RTU Master tests with Arduino via RS232 Part 2 – PDAControl
GitHub - ethicstechOSS/Modbus-Slave: A library that allows your Arduino or MSP to communicate via Modbus protocol, acting as a slave. Supports serial (RS-232, RS-485), LoRa RN-2483 and IP via Ethernet (Modbus IP).
Libreria data connection - www.cmz.it
Comunicación TCP Modbus con Arduino – Blog de Ronald -L337