Electronic taximeter having master-remote slave tariff and fare displays

Abstract

An electronic taximeter of the type including fare computing circuitry for developing a sequence of pulses at a rate representative of a fare accrual rate computed according to a particular tariff, and a tariff selecting circuit operable for selecting tariff control signals representative of the tariff at which the fare is being computed. A master-remote slave display pair displays both the accrued fare as it continually accrues, and a tariff at which the accruing fare is being computed. Both of the displays include a plurality of counters which continually count the sequence of pulses for developing a cumulative pulse count continually representative of the accrued fare. Both of the displays also include display elements for displaying numerals representative of the fare, and respective decoders for receiving the cumulative pulse count within the respective counting circuits and decoding the same to drive respective display elements. Both of the displays each include a respective tariff display circuit for receiving tariff control signals to indicate the tariff at which the fare is being computed. The master display includes a multiplexer for multiplexing the tariff control signals, and the remote slave display includes a demultiplexer for demultiplexing the same and applying the demultiplexed tariff control signals to respective tariff display indicating elements. The multiplexed tariff control signals are applied over three wires and the sequence of pulses are applied to the remote slave display over a single conductive path.