Difference between revisions of "Week 3 Lab"
From Robert-Depot
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=== Potentiometer === | === Potentiometer === | ||
[[Image:Pot_in.png]] | [[Image:Pot_in.png]] | ||
| − | * <code>A_IN</code> can be any | + | * <code>A_IN</code> can be any of the <code>Analog</code> pins (0-5) on your Freeduino. |
* Q: What will the voltage at <code>A_IN</code> be? What are the upper and lower values? | * Q: What will the voltage at <code>A_IN</code> be? What are the upper and lower values? | ||
* The important part of this sketch is the line where the microprocessor reads the analog input: | * The important part of this sketch is the line where the microprocessor reads the analog input: | ||
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* Q: Looking at the Arduino help for that function (<code>analogRead()</code>), what do you think the value <code>val</code> will be for those highest and lowest voltages at your <code>A_IN</code> pin? | * Q: Looking at the Arduino help for that function (<code>analogRead()</code>), what do you think the value <code>val</code> will be for those highest and lowest voltages at your <code>A_IN</code> pin? | ||
* Q: How can you verify your guess? Try and verify your values, in some way. Anything goes!!! | * Q: How can you verify your guess? Try and verify your values, in some way. Anything goes!!! | ||
| + | |||
=== other loads === | === other loads === | ||
==== photoresistor ==== | ==== photoresistor ==== | ||
Revision as of 22:15, 12 April 2009
from Electronic Technologies for Art
Contents
Analog Input
- File->Sketchbook->Analog->AnalogInput
Potentiometer
-
A_INcan be any of theAnalogpins (0-5) on your Freeduino. - Q: What will the voltage at
A_INbe? 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 valuevalwill be for those highest and lowest voltages at yourA_INpin? - Q: How can you verify your guess? Try and verify your values, in some way. Anything goes!!!
other loads
photoresistor
- taking the photoresistor from your 147A kit, it has a resistance of ~160k - ~10k (depending on your lighting conditions)
- Q: With the same 10k resistor and setup from the schematic above, replacing the pot with the photoresistor, what range of voltages (and corresponding data values) would you expect to see at your A_IN pin?
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
<youtube v="62gWVWCyw_w" loop="true"/>
Motor Speed Control
- Basic motor control (DC motors) see week 5
Sound, Tone Generation
- sounds, tone generation
