Controller for a coin telephone set.

摘要

A microcomputer controlled coin telephone set prevents coin call fraud and also checks the operational readiness of the telephone set to prevent the acceptance of coins into a hopper for later collection by a coin box unless or until the set is fully functional. Capable of being interrogated remotely, a local memory is used for storing coin deposit information and generating coin deposit signals in order of deposit to a central office.

In those instances where the line power drops below that necessary for full operation as a coin telephone, low power sensing circuits (111) convert the telephone to the POTS mode which allows speech and dialing capabilities. Similarly, any type of chute failure, or a full hopper causes the telephone to revert to the POTS mode. While in the POTS mode, any coins deposited in the telephone are returned to the customer.