| 
  • If you are citizen of an European Union member nation, you may not use this service unless you are at least 16 years old.

  • Social distancing? Try a better way to work remotely on your online files. Dokkio, a new product from PBworks, can help your team find, organize, and collaborate on your Drive, Gmail, Dropbox, Box, and Slack files. Sign up for free.

View
 

Curtis Ryan Lab 3

Page history last edited by zahraa@... 4 years, 9 months ago

Ryan Curtis

EE 47

Summer 2015

Lab 3

 

Part A

a. How would you change the code to make the song play twice as fast?

Change to following line:

int noteDuration = 1000 / noteDurations[thisNote];

So that it reads:

int noteDuration = 500 / noteDurations[thisNote];

b. What song is playing? ;-)

It is playing the theme song from Star Wars.


Part B

a. What voltage level do you need to power your display?

You need around 5V to power the LCD display.


b. What was one mistake you made when wiring up the display? How did you fix it?

I made a mistake in the wiring of the potentiometer and had to rearrange the leads until it was able to turn on the LCD


c. What line of code do you need to change to make it flash your name instead of "Hello World"?

I changed the line lcd.print("Hello World"); to be lcd.print("Ryan Curtis");


Part C

1.

a. Post a copy of your new code in your lab writeup.

 

int sensorPin = A0;    // select the input pin for the potentiometer

int ledPin = 13;      // select the pin for the LED

int sensorValue = 0;  // variable to store the value coming from the sensor

 

void setup() {

  // declare the ledPin as an OUTPUT:

  pinMode(ledPin, OUTPUT);

}

 

void loop() {

  // read the value from the sensor:

  sensorValue = analogRead(sensorPin);

  // adjust the brightness of LED

  analogWrite(ledPin, sensorValue/170);

}

✔ 

 Correct, but It needs to be divided by 4 also because the analog input resolution is 10 bits, and the PWM output is 8 bits. The program will work without that division, although the LED will change value from high to low 4 times over a full potentiometer rotation.

 

 

2.

a. What resistance do you see with a Multimeter when the sensor is flat? When it is bent?

It is about 9000 Ohms when flat and about 30000 Ohms when bent.

✔ 

b. What kind of voltages should we expect for the Arduino analog pin based on the sensor resistance? 

We should expect between 3 and 5 V on the pin from the sensor.

✔ 

c. How does the range of the LED's brightness change compared to the potentiometer?

The range of brightness on the LED is much larger than on the potentiometer.

✔ 

d. Include a copy of your Lowly Multimeter code in your lab write-up.

// include the library code:

#include <LiquidCrystal.h>

 

// initialize the library with the numbers of the interface pins

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

int sensorPin = A0;    // select the input pin for the potentiometer

int ledPin = 13;      // select the pin for the LED

int sensorValue = 0;  // variable to store the value coming from the sensor

 

void setup() {

  // set up the LCD's number of columns and rows:

  lcd.begin(16, 2);

  pinMode(ledPin, OUTPUT);

}

 

void loop() {

  // read the value from the sensor:

  sensorValue = analogRead(sensorPin);

  // adjust the brightness of LED

  analogWrite(ledPin, sensorValue/170);

  // Print a message to the LCD.

  lcd.clear();

  lcd.print(sensorValue);

}

 

 

✔ 

3.

a. What resistance values do you see from your force sensor?

It reads resistance values between 1000 and 10000 ohms depending on the force applied.

✔ 

b. What kind of relationship does the resistance have as a function of force applied? (e.g., linear?)

There is a linear relationship between the two but it has a negative slope. This means that an increase in the force will cause a linear decrease in the resistance.

✔ 

c. Include a copy of your FSR thumb wrestling code in your lab write-up.

 

// include the library code:

#include <LiquidCrystal.h>

 

// initialize the library with the numbers of the interface pins

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

int sensorPinL = A0;    // select the input pin for the potentiometer

int sensorPinR = A1;    // select the input pin for the potentiometer

int ledPin = 13;      // select the pin for the LED

int sensorValueL = 0;  // variable to store the value coming from the sensor

int sensorValueR = 0;  // variable to store the value coming from the sensor

 

void setup() {

  // set up the LCD's number of columns and rows:

  lcd.begin(16, 2);

  pinMode(ledPin, OUTPUT);

}

 

void loop() {

  // read the value from the sensors:

  sensorValueL = analogRead(sensorPin1);

  sensorValueR = analogRead(sensorPin2);

  lcd.clear(); 

  if(sensorValue1 > sensorValue2)

    lcd.print("LEFT");

  else if(sensorValue1 < sensorValue2)

    lcd.print("RIGHT");

  else

    lcd.print("Tie");

}

✔ 

Part D

a. Make a short video showing how your timer works, and what happens when time is up!

b. Post a link to the Lab 3 Timers Hall of Fame.

  

Comments (1)

xyyue@... said

at 2:06 pm on Jul 29, 2015

Great

You don't have permission to comment on this page.