The Design Of A New Type Of Textphone

The design of a new type of textphone is described in this article, which uses the latest dsPIC33F series microcontrollers and their corresponding Explorer16development board of Microchip Company as the hardware environment. Textphone is a kind of special telephone which suitable for hard hearing people and also for these elderly people, it transmits text information rather than voice information during the time of telecommunication to achieved the purpose of real-time communication. Today, the society enters to the aging society at a increasingly rapid pace, increasingly number of people are aware of the importance that the communication facilities should be designed for all people, text phone has a very broad prospects for development.dsPIC33F series is the collection of a series microcontrollers which have inexpensive but high performance characteristics, and it has realized seamlessly integrated on-chip with the SCM control capability and digital signal processing capabilities, very suitable for the development of this system, and with the Explorer16development board in connection, these can greatly reduce the cost of text telephone. The new text phone design’s primary purpose is to reduce the cost of the text phone, so that more people can enjoy the convenience of remote communication.Firstly of all, briefly introduced the background and the course of development as well as the application status at home and abroad of the textphone。 And then was the software and hardware environment which used in this system, mainly focused on the design and implementation software design of the system. The system is divided into the following several parts:Dialing function, Voice call, the v.21protocol modulation, Baudot modulation, digital filter design.Have introduced the debugging process of the textphone and evaluated it at the end of the article, the results fully proved that the system can perform well in doing the telephone call work process, and was perfectly meet the design requirements。...