Abstract: A circuit for controlling the frequency of a pulse generator associated with a microprocessor that is connected to power line frequency, uses an RC-stage which is connected ahead of the pulse generator as the frequency-determining element and which has a resistor 19 that is variable by a control signal derived from the microprocessor. The control signal is obtained by comparing the power line frequency and the pulse frequency with one another.

Abstract: A control system for the selection and storage of each phonograph record side to be played in a coin-operated juke box having a storage and credit mechanism. A microcomputer operating as a process computer has a number of inputs and outputs limited to a minimum by series-type runs. The microcomputer has a central computer unit, a set-value storage, and a write/read storage with selective access. The microcomputer unit, furthermore, is coupled with a clock or timing generator connected to a BCD for 1 out of 10 decoder, to a BCD for 7-segment decoder, to a BCD for 1 out of 16 decoder, and via these decoders to level converters with series-connected output units and input circuits in the form of a coding table, keyboard, input switch and coin switch.

Abstract: A coin computing apparatus includes an input for converting coin values received to coin unit data for storage along with other data. This data is subsequently converted to unit data for controlling operation of the device or the dispensing of articles. The storage includes a temporary storage for storing play unit data as it is received and a permanent storage device for receiving data from the temporary storage device for updating purposes. A read/write control device is included for reading the permanent storage data to the temporary storage means following interruptions such as power failures.