51单片机汇编语言实验及代码
单片机汇编语言实验及代码
以下内容为本人实验课亲自编写且通过51单片机运行实现的实验代码，有错误或者改进的地方请批评指正。
实验一：开发环境的应用
（1）将数据存储器的40H-4FH的内容复制成00H-0FH，并将40H-4FH的内容整体复制到外部数据存储器的1050H-105FH.
（2）P1口接八只二极管，使二极管逐个循环点亮
ORG 0000H
AJMP START
ORG 0100H
START:
MOV A,#00H
MOV R0,#40H
LOOP:
MOV @R0,A
INC A
INC R0
CJNE A,#10H,LOOP
SECOND:
MOV DPTR,#1050H
MOV R1,#40H
COPY:
MOV A,@R1
MOVX @DPTR,A
INC DPTR
INC R1
CJNE R1,#50H,COPY
SJMP $
END
实验二：外部中断
（1）用单脉冲信号申请中断，在中断服务程序中对输出信号进行翻转（可通过P1.0接一二极管观察）
ORG 0000H
LJMP START
ORG 0003H
LJMP INT
ORG 0100H
START:
SETB EX0
SETB PX0
SETB IT0
SETB EA
SJMP $
INT:
CPL P1.0
RETI
END
（2）用单脉冲信号申请中断，要求对中断进行累加计数，并将计数结果显示在二极管上
ORG 0000H
LJMP START
ORG 0003H
LJMP INT
ORG 0100H
START:
MOV A,#00H
MOV P1,A
SETB EX0
SETB PX0
SETB IT0
SETB EA
SJMP $
INT:
MOV P1,A
INC A
RETI
END
实验三：定时器实验
（1）用定时器1的方式1定时，P1.0节发光二极管，使二极管每秒闪烁五次
ORG 0000H
LJMP MAIN
ORG 001BH
LJMP INT
ORG 0100H
MAIN:
MOV TMOD,#10H
MOV TH1,#3CH
MOV TL1,#0B0H
MOV R2,#2
SETB EA
SETB ET1
SETB TR1
SJMP $
INT:
DJNZ R2,NEXT
CPL P1.0
MOV R2,#2
NEXT:
MOV TH1,#3CH
MOV TL1,#0B0H
SETB TR1
RETI
END
（2）用定时器1的方式2计数，T1引脚接单脉冲，用P1口接二极管显示计数。
ORG 0000H
LJMP MAIN
ORG 001BH
LJMP LOOP
ORG 0100H
MAIN:
MOV TMOD,#60H
MOV TH1,#00H
MOV TL1,#00H
SETB EA
SETB ET1
SETB TF1
SETB TR1
SJMP $
LOOP:
MOV P1,TL1
LJMP LOOP
RETI
END
实验四：串行通信
波特率2400 bit/s。PC发送8个字节的数据给单片机，单片机接受完数据后发送两个字节55H和AAH给PC 机（使用查询方式）。
ORG 0000H
AJMP MAIN
ORG 0030H
MAIN:
MOV SCON,#50H
MOV PCON,#00H
MOV TMOD,#20H
SETB TR1
MOV TL1,#0F3H
MOV TH1,#0F3H
LOOP:
MOV R0,#30H
MOV R1,#08H
WAIT1:
JBC RI,RECEIVE
SJMP WAIT1
RECEIVE:
MOV A,SBUF
MOV @R0,A
INC R0
DJNZ R1,WAIT1
MOV A,#55H
MOV SBUF,A
WAIT21:
JBC TI,SEND
SJMP WAIT21
SEND:
MOV A,#0AAH
MOV SBUF,A
WAIT22:
JNB TI,WAIT22
CLR TI
SJMP LOOP
END
实验五：数码管显示及键盘扫描
（1）将30H-32H中存储的6位十进制数在6个数码管上显示出来（要求编写一个将内存单元中的压缩BCD码转换为两个七段显示码的子程序和延时子程序）
ORG 0000H
LJMP MAIN
ORG 0030H
MAIN:
MOV 30H,#12H
MOV 31H,#34H
MOV 32H,#56H
MOV R0,#30H
MOV R1,#20H
BCD:
MOV A,@R0
SWAP A
ANL A,#0FH
ACALL CTAB
MOV R2,A
MOV A,@R0
ANL A,#0FH
ACALL CTAB
MOV R3,A
MOV DPTR,#8002H
MOV A,R1
MOVX @DPTR,A
MOV DPTR,#8004H
MOV A,R2
MOVX @DPTR,A
MOV A,R1
RR A
MOV R1,A
LCALL DLEY
MOV DPTR,#8002H
MOV A,R1
MOVX @DPTR,A
MOV DPTR,#8004H
MOV A,R3
MOVX @DPTR,A
MOV A,R1
RR A
MOV R1,A
LCALL DLEY
INC R0
CJNE R0,#33H,BCD
LJMP MAIN
CTAB:
PUSH DPH
PUSH DPL
MOV DPTR,#TAB
MOVC A,@A+DPTR
POP DPL
POP DPH
RET
TAB:
DB 3FH,06H,5BH,4FH,66H,6DH,7DH,07H,7FH,6FH,77H,7CH,39H,5EH,79H,71H
DLEY:
MOV R7,#02H
DL:MOV R6,#0FFH
DL1:DJNZ R6,DL1
DJNZ R7,DL
RET
END
（2）扫描矩阵键盘，将对应键盘值送LED显示
ORG 0000H
LJMP START
ORG 1000H
START:
ACALL KEY1
AJMP START
KEY1: ACALL KEY14
JNZ KEY3
KEY2: ACALL KEY16
AJMP KEY1
KEY3: ACALL KEY16
ACALL DELAY
ACALL KEY14
JNZ KEY4
ACALL KEY16
AJMP KEY1
KEY4: MOV R2, #0FEH
MOV R4, #00H
KEY5: MOV DPTR,#8002H
MOV A, R2
MOVX @DPTR, A
MOV DPTR,#8001H
MOVX A,@DPTR
JB ACC.0,KEY6
MOV A, #00H
AJMP KEY9
KEY6: JB ACC.1,KEY7
MOV A, #06H
AJMP KEY9
KEY7: JB ACC.2,KEY8
MOV A, #0CH
AJMP KEY9
KEY8: JB ACC.3, KEY12
MOV A, #12H
KEY9: ADD A, R4
KEY10: MOV R5,A
KEY11: ACALL KEY14
JNZ KEY11
MOV A,R5
ACALL KEY15
RET
KEY12: INC R4
MOV A, R2
JNB ACC.5,KEY13
RL A
MOV R2, A
AJMP KEY5
KEY13: AJMP KEY1
KEY14: MOV DPTR,#8002H
MOV A,#00H
MOVX @DPTR,A
MOV DPTR,#8001H
MOVX A,@DPTR
CPL A
ANL A, #0FH
RET
KEY15: MOV DPTR,#TABLE
MOVC A,@A+DPTR
MOV R3,A
KEY16: MOV DPTR,#8002H
MOV A,#01H
MOVX @DPTR,A
MOV DPTR,#8004H
MOV A,R3
MOVX @DPTR,A
ACALL DELAY
RET
DELAY: MOV R7,#12
LOOP: MOV R6,#250
DJNZ R6,$
DJNZ R7,LOOP
RET
TABLE:
DB 7EH,7EH,5EH,79H,71H,3FH,7EH,7EH,39H,4FH,5BH,06H,7EH,7EH,7CH,7DH,6DH,66H ,7EH,7EH,77H,6FH,7FH,07H
END
实验六：D/A和A/D
（1）利用实验箱上的电位器提供模拟量输入，将模拟量转换成二进制数字量，将转换的结果用P1口输出到二极管显示；
ORG 0000H
LJMP MAIN
ORG 0100H
MAIN:
MOV DPTR,#8000H
MOV A,#00H
MOVX @DPTR,A
MOV R2,#100
DJNZ R2,$
MOVX A,@DPTR
MOV P1,A
LJMP MAIN
END
（2）用DAC0832将一个数值转换为模拟电压，该模拟电压接ADC0809的一个模拟输入进行模/数转换，转换结果通过P1口送到二极管显示。
ORG 0000H
LJMP MAIN
ORG 0100H
MAIN:
MOV A,#90H
MOV DPTR,#9000H
MOVX @DPTR,A
MOV DPTR,#8000H
MOVX @DPTR,A
MOV R2,#64H
DJNZ R2,$
MOVX A,@DPTR
MOV P1,A
SJMP $
END
实验七：电子钟
实现一个24小时制的电子钟程序，在6个数码管上显示时分秒（用定时器0中断更新计时，以压缩BCD码形式保存在内部RAM的30H、31H和32H单元）；可以通过串行口调时！
ORG 0000H
AJMP MAIN
ORG 000BH
LJMP CLOCK
ORG 0023H
LJMP INPUT
ORG 0100H
MAIN:
MOV TMOD,#21H
CLR A
MOV 30H,A
MOV 31H,A
MOV 32H,A
MOV TH0,#3CH
MOV TL0,#0B0H
MOV 50H,#14H ;50 * 20
MOV TH1,#0F3H
MOV TL1,#0F3H ;波特率
MOV SCON,#50H
SETB PS
MOV IE,#92H
SETB TR1
SETB TR0
SLED:
MOV R0,#30H
MOV R1,#20H
LJMP LED
CLOCK:
MOV TH0,#3CH
MOV TL0,#0B0H
DJNZ 50H,RETURN
MOV 50H,#14H
MOV A,#01H
ADD A,32H
DA A
MOV 32H,A
CJNE A,#60H,RETURN
MOV 32H,#00H
MOV A,#01H
ADD A,31H
DA A
MOV 31H,A
CJNE A,#60H,RETURN
MOV 31H,#00H
MOV A,#01H
ADD A,30H
DA A
MOV 30H,A
CJNE A,#24H,RETURN
MOV 30H,#00H
RETURN:
RETI
LED:
MOV A,@R0
SWAP A
ANL A,#0FH
ACALL CTAB
MOV R2,A
MOV A,@R0
ANL A,#0FH
LCALL CTAB
MOV R3,A
MOV DPTR,#8002H
MOV A,R1
MOVX @DPTR,A
MOV DPTR,#8004H
MOV A,R2
MOVX @DPTR,A
MOV A,R1
RR A
MOV R1,A
LCALL DLY
MOV DPTR,#8002H
MOV A,R1
MOVX @DPTR,A
MOV DPTR,#8004H
MOV A,R3
MOVX @DPTR,A
MOV A,R1
RR A
MOV R1,A
LCALL DLY
INC R0
CJNE R0,#33H,LED
LJMP SLED
CTAB:
PUSH DPH
PUSH DPL
MOV DPTR,#TAB
MOVC A,@A+DPTR
POP DPL
POP DPH
RET
INPUT:
CLR RI
CLR EA
MOV 30H,SBUF
JNB RI,$
CLR RI
MOV 31H,SBUF
JNB RI,$
CLR RI
MOV 32H,SBUF
SETB EA
RETI
TAB:
DB 3FH,06H,5BH,4FH,66H,6DH,7DH,07H,7FH,6FH
DLY:
MOV R7,#02H
DL:
MOV R6,#0FFH
DL1:
DJNZ R6,DL1
DJNZ R7,DL
RET
END