8255A端口地址300H~303H,A组和B组均为方式0,端口A为输出,端口B为输入,PC低4位输入,高4位输出,编程实现将从C口低4位读入的值从高4位送出
MOV DX,303H
MOV AL,83H
OUT DX,AL
MOV DX,302H
IN AL,DX
MOV CL,4
SHL AL,CL
OUT DX,AL
2024-01-14 14:03:16
8255A端口地址300H~303H,A组和B组均为方式0,端口A为输出,端口B为输入,PC低4位输入,高4位输出,编程实现将从C口低4位读入的值从高4位送出
MOV DX,303H
MOV AL,83H
OUT DX,AL
MOV DX,302H
IN AL,DX
MOV CL,4
SHL AL,CL
OUT DX,AL