Abstract: A microprocessor based sequence controller for a vending machine performs sequences of functions required for the vending machine operation. The microprocessor unit has two separate storage sections, one of which is not alterable and contains the basic program for the vending machine. The other section is alterable and contains adjustable timing modifications of the basic program. The alterable storage section is modifiable through the use of a separate, selectively connectable service module, which is not normally connected with the sequenced controller during normal vending operations. The start and stop times of each function of the sequence of functions are independently modifiable, and an interlock is provided to assure against unintentional modification of the start and stop times.

Abstract: A microprocessor based sequence controller is disclosed in connection with a soup and beverage vending machine, in which sequences of functions required in the operation of the vending machine are under the control of the microprocessor unit. The microprocessor unit has two separate storage sections, one of which is not alterable and contains the basic program for the vending machine. The other section is alterable and contains adjustable modifications of the basic program. The alterable storage section is modifiable through the use of a separate service module, which is not normally connected with the sequence controller during normal vending operations. The start and stop times of each function of the sequence of functions are independently modifiable, and an interlock is provided to assure against unintentional modification of the start and stop times. The integrity of the stored modifications is automatically checked periodically, and the stored modifications are ignored if the integrity check fails.