Efficient collection of information from vending machines

摘要

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 indicia provides sufficient information for the central processing system to update the data kept at the central processing system to reflect new vending information. Preferably, reference vending data is kept at the vending machine and at the central processing system. New vending data is compared with the reference vending data to identify differences between the new vending data and the reference vending data. These differences are used to generate the difference indicia sent to the central processing system. Upon receipt by the central processing system, the difference indicia is used to modify the reference vending data stored at the central processing system to reflect the new vending data.