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Elenco Snap Circuits SnapMicro ® I Standard User Manual

Page 63

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Project 17, The Photo Resistor (RP) or Light Dependent Resistor

RP is an example of an analogue sensor that drops from a very high resistance to a low resistance

as light is increased. It is connected between the micro-controller input pin 2 and ground. A 100k

resistor from B+ to pin 2 allows the voltage on pin 2 to rise when it is dark and fall when there is light on
RP. Build the snap circuit shown here.

























Next page shows program and flowchart.

B

C

D

E

F

2

3

4

5

6

A

G

1

7

8

9

10

To Computer

1

1

2

2

2

1

2

2

2

1

1

1

2

1

1

2

2

See also other documents in the category Elenco Toys: