Simply, it’s an Arduino library for communicating with Modbus slaves over RS232/485 via RTU (remote terminal unit) protocol. In conclusion, the Modbus 2-channel 5V relay module is a very useful device ...

This Arduino Uno setup can be powered by a 6F22 9V battery or ... A few more significant details about this Chinese “2 Relay Module” are worth noting, especially if you are using it for the first time ...

The Raspberry Pi is a credit card-sized computer capable of running full-fledged Linux distributions such as Raspberry Pi OS, ...

The Arduino acts as the brains of the operation while an off-the-shelf NFC/RFID reader module is used to read ... the Arduino triggers a relay which can then be used to control just about anything.