CSCI 255 — Going analog with an Arduino

The digital world

In a recent lab you learned about the digital side of the Arduino by using pinMode(), digitalRead() and digitalWrite().

The basic ideas

• Analog to digital conversion (ADC)
• Pulse width modulation (PWM) to mimic digital to analog conversion (DAC)
• tone() to mimic music
• low pass filters to smooth the signal
• Pulse Density Modulation for serious audio

Trying it out

Try out some of these Arduino tutorials to learn a bit more.

• Using to potentiometer
• Displaying an analog signal — it’s always good to start here
• Using PWM
• Fading an LED with a pot
• Controlling with a light dependent resistor (LDR) — requires some tuning

Making Music

You can try the Tone Melody tutorial. It’s fun and we’ll try a bit-banging version later in the semester.

You can also make a “instrument” following the Tone Pitch Follower tutorial. I suggest you use a pot rather than an LDR. Using map and log make the instrument a bit easier to control.