Timer circuit for vending machine

摘要

The circuit includes a switch array for setting two conditions, one for defining the length of the vend period and the other for defining the coinage necessary to initiate the vend period. A binary counter is coupled by the switch array to a decoder circuit, and the binary counter is first counted incrementally in response to coinage insertion until the correct coinage has been received at which time the counter is enabled to continue counting through a timing cycle defining the vend period. At the end of the vend period the circuit is reset for future usage.