Remote units with Digital/analog Input and Output for IoT application. Communication is based on MQTT protocol.
The unit is composed by ATmega 2560 Arduino board connected to a A6 gprs module.
N° 6 digital input
N° 2 temperature input DS18B20 sensors
N° 1 analog input (Volt)
N° 2 digital output
The software is based with TinyGsm library https://github.com/vshymanskyy/TinyGSM. A real-time clock is implemented using DS3232 module and related library. A MQTT function is derived by a PubSubClient library https://github.com/knolleary/pubsubclient. Digital input is controlled by a PushButton library https://github.com/pololu/pushbutton-arduino. Temperature input use a DS18B20 probe controlled by a related library.