1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
D D
C C
B B
A A
Title
Number RevisionSize
A3
Date: 2021/7/15 Sheet of
File: E:\电路城\音乐盒(8255)\原理图\Sheet1.SchDocDrawn 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
P2.0
21
P2.1
22
P2.2
23
P2.3
24
P2.4
25
P2.5
26
P2.6
27
P2.7
28
PSEN
29
ALE/PROG
30
EA
31
P0.7
32
P0.6
33
P0.5
34
P0.4
35
P0.3
36
P0.2
37
P0.1
38
P0.0
39
VCC
40
U1
80511 2
Y1
XTAL
30pF
C2
Cap
10uF
C1
Cap Pol1
30pF
C3
Cap
10K
R1
Res2
GND
VCC
1
2
3
4
5
6
7
8
9
RP1
RESP
S1
SW-PB
Q1
PNP
LS1
Speaker
VCC
GND
10K
R2
Res2
S2
SW-PB
S3
SW-PB
S4
SW-PB
S5
SW-PB
S6
SW-PB
S7
SW-PB
S8
SW-PB
S9
SW-PB
S10
SW-PB
S11
SW-PB
S12
SW-PB
S13
SW-PB
S14
SW-PB
S15
SW-PB
S16
SW-PB
S17
SW-PB
P30
P31
P32
P33
P34
P35
P36
P37
P10
P11
P12
P13
P14
P15
P16
P17
Vin Vout
GND
7805
Volt Reg
0.1uF
C5
Cap
100uF
C4
Cap Pol1
0.1uF
C7
Cap
100uF
C6
Cap Pol1
1
2
P1
电源接口
GND
VCC
P00
P01
P02
P03
P04
P05
P06
P07
P32
D0
3
D1
4
D2
7
D3
8
D4
13
D5
14
D6
17
D7
18
OE
1
LE
11
Q0
2
Q1
5
Q2
6
Q3
9
Q4
12
Q5
15
Q6
16
Q7
19
U4
74373
GND
P00
P01
P02
P03
P04
P05
P06
P07
D0
34
D1
33
D2
32
D3
31
D4
30
D5
29
D6
28
D7
27
RD
5
WR
36
A0
9
A1
8
RESET
35
CS
6
PA0
4
PA1
3
PA2
2
PA3
1
PA4
40
PA5
39
PA6
38
PA7
37
PB0
18
PB1
19
PB2
20
PB3
21
PB4
22
PB5
23
PB6
24
PB7
25
PC0
14
PC1
15
PC2
16
PC3
17
PC4
13
PC5
12
PC6
11
PC7
10
U5
8255
P00
P01
P02
P03
P04
P05
P06
P07
P36
P37
1OE
1
1A0
2
2Y3
3
VCC
20
2OE
19
1Y0
18
1A1
4
2A4
17
2Y2
5
1A2
6
2Y1
7
1Y1
16
2A3
15
1Y2
14
1A3
8
2A2
13
2Y0
9
1Y3
12
GND
10
2A0
11
U6
74LS240
PA0
PA1
PA2
PA3
PA4
PA5
PA6
PA7
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
GND
GND
GND
VCC
PA0
D7
PA1
D6
PA2
D5
PA3
D4
D0
PA7
D1
PA6
D2
PA5
D3
PA4
A
B
C
D
E
F
G
DP
1
2
3
4
5
6
7
8
DS1
D0
D1
D2
D3
D4
D5
D6
D7
1A
1
1Y
2
2A
3
2Y
4
3A
5
3Y
6
GND
7
6Y
8
6A
9
5Y
10
5A
11
4Y
12
4A
13
VCC
14
U2
7404
GND
VCC
PB0
W1
PB1
W2
PB2
W3
PB3
W4
PB4
W5
PB5
W6
1A
1
1Y
2
2A
3
2Y
4
3A
5
3Y
6
GND
7
6Y
8
6A
9
5Y
10
5A
11
4Y
12
4A
13
VCC
14
U3
7404
GND
VCC
PB6
W7
PB7
W8
W1
W2
W3
W4
W5
W6
W7
W8