A.10H
B.20H
C.30H
D.50H
5、若R1=30H,A=40H,(30H)=60H,(40H)=08H。试分析执行下列程序段后A的变化。 MOV A,@R1 MOV @R1,40H MOV 40H,A MOV R1,#7FH 则A=()A.40HB.08HC.7FHD.60H
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设(R0)=20H,(R1)=30H,(20H)=20H,(21H)=30H,(22H)=40H,(30H)=E0H,(31H)=50H,(32H)=60H。 CLR C MOV R2, #3 LOOP: MOV A, @R0 ADDC A, @R1 MOV @R0, A INC R0 INC R1 DJNZ R2, LOOP SJMP $ 程序执行后,(R0)= 。 注意:答案用十六进制,十六进制数用大写字母H表示。
若R1=30H,A=40H,(30H)=60H,(40H)=08H。试分析执行下列程序段后A的变化。 MOV A,@R1 MOV @R1,40H MOV 40H,A MOV R1,#7FH 则A=()A.40HB.08HC.7FHD.60H
设(R0)=20H,(R1)=30H,(20H)=20H,(21H)=30H,(22H)=40H,(30H)=E0H,(31H)=50H,(32H)=60H。 CLR C MOV R2, #3 LOOP: MOV A, @R0 ADDC A, @R1 MOV @R0, A INC R0 INC R1 DJNZ R2, LOOP SJMP $ 程序执行后,(20H)= 。 注意:答案用十六进制,十六进制数用大写字母H表示。
如果R1=30H,A=40H,(30H)=60H,(40H)=08H。试分析执行下列程序段后R1是多少 MOV A,@R1 MOV @R1,40H MOV 40H,A MOV R1,#7FH R1=()A.40HB.08HC.7FHD.60H
9、设(R0)=20H,(R1)=30H,(20H)=20H,(21H)=30H,(22H)=40H,(30H)=E0H,(31H)=50H,(32H)=60H。 CLR C MOV R2, #3 LOOP: MOV A, @R0 ADDC A, @R1 MOV @R0, A INC R0 INC R1 DJNZ R2, LOOP SJMP $ 程序执行后,(R0)= 。 注意:答案用十六进制,十六进制数用大写字母H表示。
8、设(R0)=20H,(R1)=30H,(20H)=20H,(21H)=30H,(22H)=40H,(30H)=E0H,(31H)=50H,(32H)=60H。 CLR C MOV R2, #3 LOOP: MOV A, @R0 ADDC A, @R1 MOV @R0, A INC R0 INC R1 DJNZ R2, LOOP SJMP $ 程序执行后,(20H)= 。 注意:答案用十六进制,十六进制数用大写字母H表示。