基于单片机语音播报数字多用表.doc

基于单片机的语音播报数字多用表摘要：本系统设计了一个基于AT89S52单片机控制的语音播报数字多用表。通过将测量参数R、L、C、I、V等经过频率转换电路，将对应的参数值转换成相应的频率，再通过AT89S52单片机的T0口对此频率进行采样计数，经过单片机内部处理后将频率恢复成实际数据值，在LED数码显示管上显示，并通过ISD1420语音芯片播报出来。通常的仪表测量是通过谐振法、电桥法或是伏安法来测量数据，在测量时误差比较大，而本设计采用将预测参数转换成相应频率后再处理、恢复出数据，测量误差比较小，从而提高了仪表的精确度。本设计在显示测量数据的值后，还用语音芯片电路，将测量的值通过语音的方式播报出来，从而减小了因视觉误差而带来的读数误差，进一步提高了仪表的测量精确度。关键字：AT89S52；语音播报；频率转换；ISD1420 voice broadcast digital multimeter system based on MCU Abstract: This design designed a voice broadcast digital multimeter system based on MCU AT89S52.The parameters R, L, C, I ,V will be changed into a freauency by a frequency conversion circuit. Then the parameters will be measured through the T0 of MCU AT89S52 to sampling and count the frdauency of the corresponding parameters. And now through the MCU AT89S52 to compute the freauency and educe the value of the parameters, lastly let the value in the LED digital display tube display, and broadcast by the ISD1420 voice chip. Usually, the measure of meters are resonance method, bridge or voltammetry, but use these methods will make some more errors. However, in this design, after the parameters will measured changed into corresponding frequencies, then dispose the frequencies, resume the parameters value. Use this method to measure the parameters will make a little error, and enhance the system’s measuring precision. In this design, the parameters value will be broadcasted out using the voice-chip circuit, then cut down the error witch arosed by vision, so, can enhance the system’s precision ulteriorly. Keywords: AT89S52; voice broadcast; frequency conversion; ISD1420 目 录 引 言 1 第一章 方案设计比较、选择 2 1.1 测量电路方案比较选择 2 1.2 主控芯片方案比较选择 3 1.3 语音播报控制芯片的选择 3 1.4 显示电路方案比较选择 3 1.5 总体方案选择与设计 4 第二章 硬件电路设计 5 2.1 测量电路设计 5 2.1.1 Rx、Cx测量电路的设计 5 2.1.2 Lx测量电路的设计 7 2.1.3 电压、电流测量电路的设计 10 2.2 单片机控制系统的设计 11 2.2.1 AT89S52芯片介绍 11 2.2.2 AT89S52最小系统电路设计 14 2.3 语音播报模块电路的设计 15 2.4 LED显示电路及指示灯电路 19 2.4.1 LED数码管显示电路 19 2.4.2 系统指示灯电路 20 2.5 选择电路的设计 20 2.6 电源电路设计 21 2.7 系统PCB