DLDIMOVAH2INT21HPUSHDXMOVDX21BHMOVAL82HOUTDXALWAIT2MOVDX218HMOVAL0OUTDXALMOVDX219HINALDXANDAL03HCMPAL03HJNZWAIT2POPDXRETKEYENDPCODEENDSENDSTART
f64实验（2）8255并行接口（LED）实验实验3（）并行接口（并行接口）
８255个子工作于方式0，此时PA、PB、PC均为可独立输入输出的并行口。8255的各寄存器对应的端口地址为：PA口：218H；PB口：219H；PC口：21AH；控制口：21BH参考源程序
PC55EQU21AHP55CTLEQU21BHDATASEGMENTMESS1DB’左循环按1’0DH0AH’’DB’右循环按2’0DH0AH’’DB’间隔闪烁按3’0DH0AH’’DB’退出按4’0DH0AH’’MESS2DB’按无效键继续选择’0DH0AH’’MESS3DB’按任意键退回主菜单’0DH0AH’’DATAENDSSTACKSEGMENTSTADB20DUPTOPEQULENGTHSTASTACKENDSCODESEGMENTASSUMECSCODEDSDATASSSTACKESDATASTARTMOVAXDATA初始化MOVDSAXMOVAXSTACKMOVSSAXMOVSPTOPMOVSPAXMOVDXP55CTLMOVAL80HOUTDXALBGLEADXMESS1MOVAH09HINT21HMOVAH08H等待有键按下INT21HPUSHAXLEADXMESS3MOVAH09HINT21HPOPAXMOVAHALCMPAL’1’JZZXH进入各种循环MOVALAHCMPAL’2’JZYXHMOVALAHCMPAL’3’JZJGSMOVALAHCMPAL’4’JNZWXJMTQITWXLEADXMESS2无效按键提示信息MOVAH09HINT21HJMPBG
fZXHMOVDX21AH左循环MOVAL0FEHBBOUTDXALMOVCX0FFFFHL1LOOPL1ROLAL1PUSHAXPUSHDXMOVDL0FFHMOVAH06HINT21HJNZBGPOPDXPOPAXJMPBBYXHMOVDX21AH右循环MOVAL0FEHEEOUTDXALMOVCX0FFFHL2LOOPL2RORAL1PUSHAXPUSHDXMOVDL0FFHMOVAH06HINT21HJNZBGPOPDXPOPAXJMPEEJGSMOVDX21AH间隔闪烁MOVAL55HHHOUTDXALMOVCX0FFFFHL3LOOPL3NOTALPUSHAXPUSHDXMOVDL0FFHMOVAH06HINT21HJNZBG1POPDXPOPAXJMPHHBG1JMPBGQITMOVAX4C00HINT21HCODEENDSENDSTART
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实验4实验8259A中断控制器实验中断控制器实验
参考程序清单
DATASEGMENTTS1DB’组合推键开关设置编码，按下单脉冲键，观察LED显示，注意上升沿或下降沿触发’0DH0AH’’
fTS2DB’并行接口8255C口采集数据并显示，请观察、记录。’’’DATAENDSCODESEGMENTASSUMECSCODEDSDATASTARTMOVAXCSMOVDSAXLEADXINTPROGMOVAH25H25H功能，设置新中断向量MOVAL0AHINT21HCLI关中断MOVDX21HINALDXANDAL11111011B解屏蔽，OCW1相应位置0即可OUTDXALMOVCX10MOVSI0041HSTIMOVAXDATAMOVDSAXLEADXTS1MOVAH9INT21HYYNOPJMPYYINTPROGPUSHDSMOVAXDATAMOVDSAXLESDXTS2MOVAH9INT21HMOVCX05HMOVDL20HMOVAH2XH0INT21HLOOPXH0MOVDXSIMOVAH2INT21HMOVDL0DHINT21HMOVDL0AHINT21HMOVDX21BHMOVAL88HOUTDXALMOVDX21AHINALDXMOVCL4RORALCLNOTALOUr