1. A method of inputting a user input access combination in order to gain authorized entry into a secure location, the method comprising: providing an input device having a first input key, a second input key, and a display; randomly generating a first character and a second character on the display; inputting the user input access combination into the input device, the user input access combination including a first user input character and a second user input character, wherein inputting the user input access combination comprises: pressing the first input key to change the first randomly generated character to the first user input character; pressing the second input key to change the second randomly generated character to the second user input character; and comparing the user input access combination with an authorized access combination.