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1 2 3 4 5 6
A
B
C
D
654321
D
C
B
A
Title
Number RevisionSize
B
Date: 30-Mar-2012 Sheet of
File: E:\项目开发\超声波测距\图纸\超声波测距-带报警.ddbDrawn By:
P1.0
1
P1.1
2
P1.2
3
P1.3
4
P1.4
5
P1.5
6
P1.6
7
P1.7
8
RST
9
P3.0(RXD)
10
P3.1(TXD)
11
P3.2(INT0)
12
P3.3(INT1)
13
P3.4(T0)
14
P3.5(T1)
15
P3.6(WR)
16
P3.7(RD)
17
XTAL2
18
XTAL1
19
GND
20
(A8)P2.0
21
(A9)P2.1
22
(A10) P2.2
23
(A11) P2.3
24
(A12) P2.4
25
(A13) P2.5
26
(A14) P2.6
27
(A15) P2.7
28
PSEN
29
ALE/PROG
30
EA/VPP
31
(AD7)P0.7
32
(AD6)P0.6
33
(AD5)P0.5
34
(AD4)P0.4
35
(AD3)P0.3
36
(AD2)P0.2
37
(AD1)P0.1
38
(AD0)P0.0
39
VCC
40
U1
AT89C51
Y1 12MHz
C2
22
C3
22
e
1
d
2
dp
3
c
4
g
5
S4
6
b
7
S3
8
S2
9
f
10
a
11
S1
12
L1
4-LED
VCC
R14
10K
3
2 1
P1
DC
VCC
1
1
2
2
3
3
4
4
5
5
6
6
S1
SWITCH
A
A
F
F
B
B
E
E
D
D
dp
dp
C
C
G
G
S4
S3
S2
S1
VCC
+
C1
10uF
R1
510
R2
510
R3
510
R4
510
R5
510
R6
510
R7
510
R8
510
VCC
R9
4.7K
R10
4.7K
R11
4.7K
R12
4.7K
b
c
e
Q1
8550
b
c
e
Q4
8550
b
c
e
Q2
8550
b
ce
Q3
8550
S1
S2
S3
S4
1A
1
1Y
2
2A
3
2Y
4
3A
5
3Y
6
GND
7
4Y
8
4A
9
5Y
10
5A
11
6Y
12
6A
13
VCC
14
U2
74HC04
IN
1
C1
2
C2
3
GND
4
F0
5
C3
6
OUT
7
VCC
8
U3
CX20106A
VCC
R15
1K
R16
1K
R17
4.7K
R18
200K
VCC
VCC
B1
T
B2
R
C4
104
C7
331
C6
1uF
C5
3.3uF R19
22K
VCC
VCC
VCC
R20
4.7K
LS1
SPEAKER
b
c e
Q5
8550
VCC