Abstract: A method and apparatus for using electronic security coupons in connection with locking mechanisms for preventing unauthorized access to or removal of internal components of vending and gaming machines. A security coupon is received in the bill validator section of the machine, the security coupon is recognized, and the locking mechanism is unlocked. The security coupon optionally can be stored in a currency cassette.

Abstract: An automatic transaction apparatus, such as a vending machine, containing a current inventory of products for purchase and including a display unit. The current product inventory stored in the apparatus is monitored and representations of products appearing on the display unit are changed in response to monitoring the current product inventory. Methods of operating the automatic transaction apparatus are also disclosed.

Abstract: A printer module for ready attachability to a portable data scanner to form an integrated portable unit is described. The printer module includes a symmetrical printer cartridge, having a printer mechanism, a printer mechanism control circuit and a paper supply. The symmetrical printer cartridge being readily removable and rotatable to facilitate lefthanded and righthanded usage. The printer module further including a bayonet configured locking arrangement to facilitate mechanical and electrical connection of the printer module with the portable data scanner.