The Design of Single-Chip Microcomputer Telepone Timer & Taximeter

This paper describes the design of telephone timer and taximeter based on the single-chip microcomputer, it points out the idea of recognizing dial pulse and dual-tone multiple frequency division dialing. Meanuhile, it fully uses the sources of single-chip microcomputer and notes to bring software into full play. Obviously, it features as follows: proper structural, easy using and high cost perfermance.