Arduino pro micro RFID and servo Answered
I've successfully implemented Door Unlock system described in this tutorial. At first I used Arduino Uno and RFID RC522 Reader and MG90S Micro servo.
When I used Arduino Uno with Arduino Pro Micro for arduino ATmega32U4 5V/16MHz, the RFID reader stops wirking after pluging the servo. Since Arduino Pro Micro have only 5v output, I used resistors to downgrade 5v to 3v in order to poser the RFID reader. I used same output 'vcc' to select 5v for the servo and 3v converted to the reader.
The problem is that each component woks perfectly independent each other, however, when I place them together they stop working.