实现将DX:AX中存放的32位数扩大四倍,正确的程序段是()
A.SHLAX,2ROLDX,2
B.RCLAX,2SHLDX,2
C.MOVCX,2LOP:SHLAX,1RCLDX,1LOOPLOP
D.SHLAX,1SHLAX,1RCLDX,1RCLDX,1
A.SHLAX,2ROLDX,2
B.RCLAX,2SHLDX,2
C.MOVCX,2LOP:SHLAX,1RCLDX,1LOOPLOP
D.SHLAX,1SHLAX,1RCLDX,1RCLDX,1
A AX=9ABCH DX=8765H
B AX=9ABCH DX=9ABCH
C AX=8765H DX=8765H
D.AX=8765H DX=9ABCH
若 (AX=1234H,(DX=89ABH,执行 XCHG AX,DX指令后 ,AX 、 DX 中的内容应()
A (AX=1234H (DX=1234H
B (AX=12ABH (DX=8934H
C (AX=89ABH (DX=1234H
D (AX=89ABH (DX=89ABH
A.CMP DB1,DB2
B.ADD AX,BL
C.MOV [SI],DB2
D.SUB [BX],BX
E.AND AX,[DX]
要输入端口 1234H 中的 8 位数据,其指令应是()
A MOV DX, 1234H
B MOV DX , 1234H OUT DX, AL 1N AL , DX
C 1N AX , 1234H
D.OUT DX , 1234H
A.AX,BX,CX,DX;专用寄存器
B.BP,SP,SI,DI;专用寄存器
C.AX,BX,CX,DX;通用寄存器
D.CS,DS,ES,SS;段地址寄存器