Circuit Diagram我正在就上述主题在AT89C51上进行项目。我没有在硬件/软件上获得输出。我在项目中使用HC-SR04超声波传感器。距容器顶部的高度大于8厘米，当距顶部的高度小于2厘米时关闭。我自省了很多，但仍然找不到我的代码中的错误。有人可以找出代码有什么问题吗？我最怀疑传感器部分。这是代码：-
RS EQU P2.7 ;equates RS to P2.7
RW EQU P2.6 ;equates RW to P2.6
E EQU P2.5 ;equates E to P2.5
ORG 00H ;origin
MOV DPTR,#LUT ;move starting address of LUT to DPTR
CLR P3.0 ;clears P3.0(output)
SETB P3.1 ;sets p3.1(input)
MOV TMOD,#00100001B ;sets Timer1 as Mode2 timer and Timer0 as Mode1 timer
MAIN:
ACALL DINT ;calls DINT subroutine
ACALL TEXT1 ;calls TEXT1 subroutine
MOV TL1,#200D ;loads TL1 with start value
MOV TH1,#200D ;loads TH1 with reload value
MOV A,#00000000B ;loads A with all Zeros
SETB P3.0 ;sets P3.0(trigger pulse)
ACALL DELAY1 ;calls DELAY1 subroutine (1uS)
CLR P3.0 ;clears P3.0
HERE:
JNB P3.1,HERE ;loops here until echo is receive
BACK:
SETB TR1 ;starts Timer1
HERE1:
JNB TF1,HERE1 ;loop here until Timer1 roll over occurs
CLR TR1 ;stops Timer1
CLR TF1 ;clears Timer Flag 1
INC A ;Increments accumulator
JB P3.1,BACK ;jumps to label BACK if echo is still present
MOV R7,A ;saves accumulator to R7
ACALL SPLIT ;calls SPLIT subroutine
ACALL LINE2 ;calls LINE2 subroutine
ACALL LEVEL ;calls LEVEL subroutine
ACALL TEXT2 ;calls TEXT2 subroutine
ACALL TEXT3 ;calls TEXT3 subroutine
ACALL CHECK ;calls CHECK subroutine
JB P2.0,JUMP ;jumps to label JUMP if P2.0 is set
ACALL TEXT4 ;calls TEXT4 subroutine
SJMP EXIT2 ;jumps to label EXIT2
JUMP:
ACALL TEXT5 ;calls TEXT5 subroutine
EXIT2:
ACALL DELAY2 ;calls DELAY2 subroutine(1S)
SJMP MAIN ;jumps to label MAIN
CHECK:
MOV A,R7 ;loads value of R7 to accumulator
SUBB A,#20D ;subtracts 20D from A
JNC ON ;jumps to label ON if carry flag not set(A>20D)
ACALL OFF ;else calls OFF subrotine
SJMP EXIT ;jumps to label EXIT
ON:
SETB P2.0 ;sets P2.0 (motor ON)
EXIT:
CLR CY ;clears carry flag
RET ;return from subroutine
OFF:
MOV A,R7 ;loads value of R7 to accumulator
SUBB A,#5D ;subtracts 5D from A
JNC EXIT1 ;jumps to label EXIT1 if carry flag not set(A>5D)
CLR P2.0 ;else clears P2.0(motor OFF)
EXIT1:
CLR CY ;clears carry flag
RET ;return from subroutine
DELAY1:
MOV R6,#2D ;loads R6 with 2D
LABEL1:
DJNZ R6,LABEL1 ;loops here until R6 is 0
RET ;return from subroutine
DELAY2:
MOV R0,#15D ;loads R0 with 15D
BACK1:
MOV TH0,#00000000B ;loads TH0 with start value
MOV TL0,#00000000B ;loads TL0 with start value
SETB TR0 ;starts Timer0
HERE2:
JNB TF0,HERE2 ;loops here until roll over occurs
CLR TR0 ;stops Timer0
CLR TF0 ;clear Timer Flag 0
DJNZ R0,BACK1 ;loops the timer session 15 times for 1S delay
RET ;return from subroutine
TEXT1:
MOV A,#48H ;ascii of "H"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#32H ;ascii of "2"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#4FH ;ascii of "0"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#20H ;ascii of " "
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#4CH ;ascii of "L"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#45H ;ascii of "E"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#56H ;ascii of "V"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#45H ;ascii of "E"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#4CH ;ascii of "L"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#20H ;ascii of " "
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#43H ;ascii of "c"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#54H ;ascii of "T"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#52H ;ascii of "R"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#4CH ;ascii of "L"
ACALL DISPLAY ;calls DISPLAY subroutine
RET ;return from subroutine
TEXT2:
MOV A,#63H ;ascii of "c"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#6DH ;ascii of "m"
ACALL DISPLAY ;calls DISPLAY subroutine
RET ;return from subroutine
TEXT3:
MOV A,#20H ;ascii of " "
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#4DH ;ascii of "M"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#6FH ;ascii of "o"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#74H ;ascii of "t"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#6FH ;ascii of "o"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#72H ;ascii of "r"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#20H ;ascii of " "
ACALL DISPLAY ;calls DISPLAY subroutine
RET ;return from subroutine
TEXT5:
MOV A,#4FH ;ascii of "O"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#4EH ;ascii of "N"
ACALL DISPLAY ;calls DISPLAY subroutine
RET ;return from subroutine
TEXT4:
MOV A,#4FH ;ascii of "O"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#46H ;ascii of "F"
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,#46H ;ascii of "F"
ACALL DISPLAY ;calls DISPLAY subroutine
RET ;return from subroutine
SPLIT:
MOV B,#10D ;loads 10D to B
DIV AB ;divides A with B
MOV R3,B ;saves the remainder to R3 (3rd digit)
MOV B,#10D ;loads 10D to B
DIV AB ;divides A with B
MOV R2,B ;saves the remainder to R2 (2nd digit)
MOV R1,A ;saves the quotient to R1 (1st digit)
RET ;return from subroutine
LEVEL:
MOV A,R1 ;moves R1 to A (1st digit)
ACALL ASCII ;calls ASCII subroutine
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,R2 ;moves R2 to A (2nd digit)
ACALL ASCII ;calls ASCII subroutine
ACALL DISPLAY ;calls DISPLAY subroutine
MOV A,R3 ;moves R3 to A (3rd digit)
ACALL ASCII ;calls ASCII subroutine
ACALL DISPLAY ;calls DISPLAY subroutine
RET ;return from subroutine
DINT:
MOV A,#0CH ;display ON cursor OFF
ACALL CMD ;calls CMD subroutine
MOV A,#01H ;clear display screen
ACALL CMD ;calls CMD subroutine
MOV A,#06H ;increment cursor
ACALL CMD ;calls CMD subroutine
MOV A,#80H ;force cursor to the begining of 1st line
ACALL CMD ;calls CMD subroutine
MOV A,#3CH ;activate 2nd line
ACALL CMD ;calls CMD subroutine
RET ;return from subroutine
LINE2:
MOV A,#0C0H ;jump to 2nd line position 0
ACALL CMD ;calls CMD subroutine
RET ;return from subroutine
CMD:
MOV P0,A ;moves A to P0
CLR RS ;clears RS pin of LCD
CLR RW ;clears RW pin of LCD
SETB E ;sets E pin of LCD
CLR E ;clears E pin of LCD
ACALL DELAY ;calls DELAY subroutine
RET ;return from subroutine
DISPLAY:
MOV P0,A ;moves A to P0
SETB RS ;sets RS pin of LCD
CLR RW ;clears RW pin of LCD
SETB E ;sets E pin of LCD
CLR E ;clears E pin of LCD
ACALL DELAY ;calls DELAY subroutine
RET ;return from subroutine
DELAY:
CLR E ;clears E pin of LCD
CLR RS ;clears RS pin of LCD
SETB RW ;sets RW pin of LCD
MOV P0,#0FFH ;sets P0 as input
SETB E ;sets E pin of LCD
MOV A,P0 ;moves P0 to A
JB ACC.7,DELAY ;jumps back to label DELAY if ACC.7 is set
CLR E ;clears E pin of LCD
CLR RW ;clears RW pin of LCD
RET ;return from subroutine
ASCII:
MOVC A,@A+DPTR ;over-writes A with ascii code of data in A
RET ;return from subroutine
LUT:
DB 48D ;ascii of "0"
DB 49D ;ascii of "1"
DB 50D ;ascii of "2"
DB 51D ;ascii of "3"
DB 52D ;ascii of "4"
DB 53D ;ascii of "5"
DB 54D ;ascii of "6"
DB 55D ;ascii of "7"
DB 56D ;ascii of "8"
DB 57D ;ascii of "9"
END ;end statement