Week 3 Lab

from Electronic Technologies for Art

Analog Input

• File->Sketchbook->Analog->AnalogInput

Potentiometer

• Q: What will the voltage at A_IN be? What are the upper and lower values?
• The important part of this sketch is the line where the microprocessor reads the analog input:

val = analogRead(potPin); // read the value from the sensor

• Q: Looking at the Arduino help for that function (analogRead()), what do you think the value val will be for those highest and lowest voltages at V_IN?
• Q: How can you verify your guess? (... I have two ideas ... )

other loads

• photoresistor from your 147A kit... 160k - ~10k (depending on your lighting conditions).
• Q: With the same 10k resistor from the schematic above, what range of voltages (and corresponding data values) would you expect to see with this?
• strain gauge
• ultrasonic rangefinder:

Analog Output

LED Dimming

• File->Sketchbook->Examples->Analog->Fading

   analogWrite(ledpin, value);           // sets the value (range from 0 to 255) 

PWM (pulse width modulation)

• lights, fading

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Motor Speed Control

• Basic motor control (DC motors) see week 5

Sound, Tone Generation

• sounds, tone generation