An ATM includes a user interface having plural electronic ink displays. Displays can be used as identification labels. A display identifying the function of a transaction function device can be located adjacent to that device. Displays can also be used to provide instructions to machine users. A display on how to insert a card into the ATM can be located adjacent the card input slot. An display can be in direct communication with both a card reader and an encryption pin pad ("EPP"). Upon suspecting card reader tampering, the card reader can instruct the display to present a message warning of the situation. Likewise, upon suspecting EPP tampering, the EPP can instruct the display to present a warning message. Displays can also instruct a machine user on when and when not to insert their PIN depending on the mode of the EPP.