1

2

3

4

A

B

C

D

4

3

2

1

D

C

B

A

1

2

74LS05

3

4

5

6

8

9

1

SDA

6

GND

2

SCL

3

Power control

4

work / NOT work

5

+5v permanent

1
14
2
15
3
16
4
17
5
18
6
19
7
20
8
21
9
22
10
23
11
24
12
25
13

LPT 1

1 k

4.7 k

0.1 mF

14 pin 74LS05

7 pin 74LS05