A.0003H
B.0300H
C.0400H
D.0004H
A.ASSUMECS:CSEG
B.END START
C.MOV CS,CSEG MOVCS,AX
D.MOV AX,CSEG
A.ASSUMECS:CSEG
B.END START
C.MOVCS,CSEG
D.MOV AX,CSEG MOVCS,AX
以下是8051单片机定时/计数器的初始化程序(设单片机晶振频率是6MHz):T0作为定时,定时时间为______,T1作为计数,记满______溢出。
ORG 0000H
LJMP 0050H
ORG 0050H
MOV TMOD,#20H
MOV TH0,#63H
MOV TL0,#18H
MOV TH1,#9CH
MOV TL,#9CH
SETB EA
SETB TR0
SETB TR1
SJMP $
A.A
B.D
C.41H
D.44H
0RG 0000H
AJMP MAIN
0RG 001BH
AJMP INTP
ORG 0030H
MAIN:MOV TMOD, ① ;写控制字
MOV TH1,#0F0H ;写定时常数(定时1ms)
MOV TL1,#0CH
② ;启动T1
③ ;启动T0
④ ;允许T1中断
⑤ ;开放CPU中断
AJMP $ ;定时中断等待
ORG 0200 H ;T1中断服务程序
INQP:PUSH 0
MOV TH1,#0F0H ;重写定时常数
MOV TL1,#0CH
CPL P1.0 ;P1.0变反输出
⑥
⑦
⑧
答:①______;②______;③______;④______;
⑤______;⑥______;⑦______;⑧______。
设数据段中定义语句 DA1 DB 12H, 34H DA2 DW 12H, 34H 下面有语法错误的语句()
A BUF1 DW DA1
B MOV DA1+1, AX
C MOV BYTE PTR DA2+1, AL
D MOV WORD PTR DA1, AX
STACK SEGMENT STACK
DW 32 DUP()
STACK ENDS
DATA SEGMENT
BUF DB 50()
DATA ENDS
CODE SEGMENT
START PROC FAR
ASSUME CS: CODE, DS: DATA, SS: STACK
MOV AX, DATA
MOV DS, AX
LEA SI, BUF
[1]
CON:
INT 2IH
MOV [SI],AL
INC SI
[2]
JNE CON
MOV AX, 4COOH
INT 2IH
START ENDP
CODE ENDS
END START
STACK SEGMENT STACK
DW 32DUP()
STACK ENDS
DATA SEGMENT
BUF DB 50()
DATA ENDS
CODE SEGMENT
START PROC FAR
ASSUME CS:CODE,DS:DATA,SS:STACK
MOV AX,DATA
MOV DS,AX
LEA SI,BUF
(1)
CON:
INT 21H
MOV [SI],AL
INC SI
(2)
JNE CON
MOV AX,4C00H
INT 21H
START ENDP
CODE ENDS
END START
分析以下程序段,判断程序段执行完毕后,BH寄存器中的值为______。
…
MOV BH, 0
MOV BL, 15
SUB BL, 5
JZ NEXT0
MOV BH, BL
NEXT0: ADD BH, BL