This article describes how to use AD to identify the user s keyboard input metho...

本文介绍了如何用AD识别用户输入的键盘的方法，较之点阵识别有其不可替代的优势；因为如果用4*4的话须消耗8个I/O口，而如果系统有AD功能的话就可能轻松解决了。 单片机8051F330发给ARM然后发给电脑。 其原理就是利用电阻的分压，按键时产生不同的电压，再用中断快速读取电压；然后对其进行编码，通过串口软件EASYARM在个人电脑里显示；经实验观察，效果还可以。 -This article describes how to use AD to identify the user s keyboard input methods, compared with dot-matrix recognition has its irreplaceable advantages because if we use 4* 4, then to be consumed eight I/O port, and if the system function in AD, then on may be easily resolved. Singlechip 8051F330 distributed computer and then distributed to ARM. Its principle is to use the sub-ballast resistor, when keys have different voltage, and then quickly read voltage interruption then encode, through the serial port software EASYARM in the personal computer display by experimental observation, the effect can also be.