Hi to all,
I am working on RFID Attendance system with Arduino Mega 2560 + EM-18 + RTC - DS3231 + SD card module + ESP8266
I need a UPS(uninterrupted power supply) system for this setup so that it keeps on running in case when there is no power.
I am new to arduino , please guide me how i can build this UPS and power my Arduino, so that it keeps on running.
Any Suggestion & Advice??