About the design of Voice promote countdown timer
based on SCM
Profess: Electronic and Information Engineering Class: Telecom 041 Name: Xu hui
instructor: Ye guo wen
Abstract This paper was designed Voice promote countdown timer. through the existing programmers of using AT89S52 SCM, ISD1420 chip and digital control to realize the system function. In the time telling function, we use dynamic scan principle. In time adjusting setting, it has added and decreases one function. through the pressed key and the software control clock to fixed time and the time establishment's input. While in phonetic system, ISD1420 chip has both voice recording and playing function, which makes the system more reliable and operative. The designs of this system use few AT89S52 as its resource and available for adding new function in the future, it’s practical and patulous. Through the design of hardware and software part of a pilot test to the corresponding technical indicators, basic to the task of the request.