Circuit design for the mini-type data communication equipment

Many kinds of communication and data-transmitting systems have used Data communications equipments (DCE) to exchange information. The special-purpose DCE has very important practical value. This paper proposed the circuit design for a new kind of mini-type distance data exchange device. It consists of a small number of integrated circuit, telephone dial device, modulation device, central processing unit button input device and display device. The system and circuit design has been described in detail. It can be used to transmit data through public switched telephone network. It is suitable for constructing a mini scale communication network at low cost for data transmission through the PSTN.