The present invention provides an efficient system for providing vending information from vending machines to a central processing system. Difference indicia representing changes in vending information from a previous update is sent to the central processing system from a vending machine. The difference...http://www.google.fr/patents/US6754558?utm_source=gb-gplus-shareBrevet US6754558 - Efficient collection of information from vending machines
Efficient collection of information from vending machines
