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1、1.从键盘上输入0~9，通过8255方式0，A口输出，输出在数码管上显示相应数字（即我在键盘上输入5，则在数码管上显示5）。datasegmentnum1db'pleaseinputanumber(0-9):',0dh,0ah,'$'leddb3fh,06h,5bh,4fh,66h,6dh,7dh,07h,7fh,6fhdataendscodesegmentassumecs:code,ds:datastart:movax,datamovds,axmovdx,28bhmoval,80houtdx,all1:callcrlfleadx,num1movah,09hint21hmovah,01hint
2、21hcmpal,'0'jbexitcmpal,'9'jaexitsubal,30hleabx,ledxlatmovdx,288houtdx,aljmpl1exit:movah,4chint21hcrlfprocnearmovdl,0dhmovah,02hint21hmovdl,0ahmovah,02hint21hretcrlfendpcodeendsendstart2．8255方式0，A口输入，输入的数高4位不变低4位取反，在8255的C口输出，有键按下返回DOS,无键按下继续执行。codesegmentassumecs:codestart:movdx,28bhmoval,90houtdx,
3、all1:movdx,288hinal,dxxoral,0fhmovdx,28ahoutdx,almovah,1int16hjzl1movah,4chint21hcodeendsendstart3．8255方式0，C口低4位输入数据取反，在8255的C口高4位输出，有键按下返回DOS,无键按下继续执行。codesegmentassumecs:codestart:movdx,28bhmoval,81houtdx,all1:movdx,28ahinal,dxmovcl,4shlal,clxoral,0f0hmovdx,28ahoutdx,almovah,1int16hjzl1movah,4chin
4、t21hcodeends4．8255方式0，A口输入，C口输出。如果A口输入的数大于等于128，从C口输出80H;否则将输入的数高4位不变低4位取反从C口输出，有键按下返回DOS,无键按下继续执行。codesegmentassumecs:codestart:movdx,28bhmoval,90houtdx,all3:movdx,288hinal,dxcmpal,80hjael1xoral,0fhmovdx,28ahoutdx,all2:movah,1int16hjzl3movah,4chint21hl1:moval,80hmovdx,28ahoutdx,aljmpl2codeendsendst
5、art5．8255方式0，A口输入C口输出，如果A口的PA7输入为0，则L5、L2灯亮，PA7为1，则L7、L0灯亮，有键按下返回DOS,无键按下继续执行。codesegmentassumecs:codestart:movdx,28bhmoval,90houtdx,all3:movdx,288hinal,dxtestal,80hjzl1moval,81hmovdx,28ahoutdx,all2:movah,1int16hjzl3movah,4chint21hl1:movdx,28ahmoval,24houtdx,aljmpl2codeendsendstart6．8255方式0，A口输出C口输入
6、，C口输入高2为位取反低6位不变，用键盘控制程序，有键按下返回DOS,无键按下程序继续执行codesegmentassumecs:codestart:movdx,28bhmoval,89houtdx,all1:movdx,28ahinal,dxxoral,0c0hmovdx,288houtdx,almovah,1int16hjzl1movah,4chint21hcodeendsendstart7．8255方式0，A口输出到LED灯上，让灯按顺序从左到右移动显示，每显示一个灯延时一秒在显示下一个灯，有键按下返回DOS,无键按下继续执行。codesegmentassumecs:codestart:
7、movdx,28bhmoval,80houtdx,almovdx,288hmoval,01hl1:outdx,alcalltimerolal,1movah,1int16hjzl1movah,4chint21htimeprocnearpushcxmovsi,0200ht2:movcx,0t1:loopt1decsijnzt2popcxrettimeendpcodeendsendstart8．8255
