Abstract: A programmable accountability apparatus for installation into a vending machine is disclosed. The accountability apparatus comprises a plurality of monitoring wires attachable to points within the vending machine carrying AC signals selected for monitoring, means for converting the AC signals into digital signals, a microprocessor which is programmed to monitor and collect data from the digital signals, and a memory for storing both data collected from the digital signals and data for programming the microprocessor. The data for programming the microprocessor comprises a selected digital word for each monitoring wire which determines whether the occurrence of the AC signal monitored by that wire is to be counted, timed or measured in duration.

Abstract: An accountability system for a vending machine system having means for vending products and means for determining credit, the accountability system comprising a portable electronic data file module which is removable from the system, and means for collecting transaction data from the vending machine system and recording it in the portable electronic data file module. A module interlock and a power monitor are provided to ensure that accurate information is stored in the module.

Abstract: A price interface for use in connecting a calculating and control unit with a multiprice vending apparatus, the price interface including a first register for storing the initial price value during a vending cycle and a second register for storing the current price value during the vending cycle.

Abstract: Continuous power and a high rate clock are supplied to a calculator while it is in an execute mode and is actually decoding and processing input information, but lower duty cycle power and lower duty cycle clock pulses are supplied during the subsequent display mode, when the only requirement is to maintain and display selected information resulting from the execute cycle, so as to reduce the power consumption rate as compared to the rate during the execute mode. If there is no new execute mode within a selected time interval, the display is turned off and the duty cycle of the power and the clock supplied to the calculator are lowered still further so as to maintain (without displaying) selected stored information but to further reduce the rate of power consumption.