微机原理继电器实验教程文件.doc

Good is good, but better carries it.精益求精，善益求善。微机原理继电器实验-实验三继电器控制要求和代码二、实验原理与内容实验原理如图所示，编程使用8253定时，让继电器周而复始的闭合5秒钟（指示灯亮），断开5秒钟（指示灯灭）。一、实验目的1、了解微机控制直流继电器的原理2、进一步熟悉8255和8253的应用2、参考流程图开始设8255A口入，C口出PC0置位，继电器加电调延时子5秒程序PC0复位，继电器断电主程序调延时子5秒程序Datasegmentio8255equ28bhio8255aequ288hio8253equ283hio82530equ280hio82531equ281hdataendscodesegmentassumecs:codestart:movdx,io8255moval,90houtdx,almoval,01;置位outdx,alcalldelaymoval,0;复位outdx,alcalldelayjmpstartdelayprocnear;延时子程序pushdxmovdx,io8253;设8253计数器0为方式3moval,36houtdx,almovdx,io82530;8253计数器0写初值movax,10000outdx,almoval,ahoutdx,almovdx,io8253;设8253计数器1为方式0moval,70houtdx,almovdx,io82531;8253计数器1写初值movax,500outdx,almoval,ahoutdx,alpress:movah,6movdl,0ffhint21hjznext;无键按下跳转movah,4chint21hnext:movdx,io8255ainal,dxtestal,01h;测试jzpresspopdxretdelayendpcodeendsendstart-