Arduino Starter Kit - Chapter 06 Light Theremin

Hi, I'm Troy McClure Ygy Freezone. You may remember me from such tutorial as Arduino Starter Kit Explanation, and this is nothing more than another chapter of my Explanation! -big noise of hand clapping-

Today I'll display you the next chapter of the manual:

06 LIGHT THEREMIN create a musical instrument you play by waving your hands

In this chapter we will try to reproduce a Theremin (an instrument that make sound based on the movements of a musician hand around  the instrument, here for more info).

While the Arduino can't exactly replicate the sound, nor the operation behind this instrument, it is only possible to emulate them using the tone() function and a piezo sounder.

Furthermore, here the author explain an helpful method to calibrate your sensor, using a while loop in the setup() function.

Our beloved/hated wikipedia about the while loop say "The while loop is a control flow statement that allows code to be executed repeatedly based on a given boolean condition". I can't explain better than this.

Syntax: 

while (booleanCondition) {
//..
}

Into the booleanCondition in this case the author choose to put the millis() function.
The millis() function return the number of millisecond from when the Arduino is on.
Syntax:

int millis()

For play sound on a piezo you need the tone() function. Let see this function:

Syntax:

void tone(pin,freqPlay,timePlay)

Where pin is the pin which you had connected to the piezo; freqPlay is the frequency for play obtained using the map() function, we talk about that in the previous chapter, to change the range of the sensor(0-1023) to the range of the piezo (50-4000); timePlay is the time in millisecond you want to play that frequency.

As ever I don't put the entire code, because you can find it easily into the IDE.

My modification this time is not mine, or rather, I followed the advise on the manual:

So here we are, I first try to put a potentiometer:

But the sound was really to low, and I don't really like this solution.

Then I try to change the potentiometer with another photoresistor:

Built like this the operation of our Theremin is more like a real Theremin.

Unfortunately for the second photoresistor I do not put any function for modulate the voltage level like it was the volume. Because the tone() function, in her internal code, use the same condition of the analogWrite() I don't really know if these two work in the same pin.

Maybe it is possible, but I need to know how both functions work in their internal code and try to mix they together for changing both frequency and pwm.


For today it's over, next post next week.

Ygy Freezone.

Arduino Starter Kit - Chapter 05 Mood Cue

New week, new day, and new post is here.Today will treat the fifth chapter of the manual:

05 MOOD CUE clue people in to how you're doing

In this chapter they introduce how to use a potentiometer, a servomotor and his personal library.
Today I'll explain how to include an external library, how to use map() function to convert a number from a scale to another.
Plus, like every time, some little modifications to the original project.

Start talking about potentiometer: a potentiometer is a type of voltage divider. As you turn the knob, you change the ratio of the voltage between the middle pin and power. 

For prevent down of tension, they put, in parallel both to the potentiometer and the servomotor, a capacitor.

When using capacitor, I quote the manual literally, be very careful to make sure you are connecting the cathode (the side with a stripe down the side) to ground and the anode to power because if you invert it the capacitor can EXPLODE. Actually if you invert anode and cathode you can burn down the capacitor, maybe explode is a term a little bit exaggerated but possible imho.

Now, the servomotor. The servomotor usually only rotate 180°. His input is similar to the PWM, as seen in the previous chapter, and he expects a number of pulse that him reads to know what angle to move to.

For generate the pulse you can either write your personal code or use the native library Servo.h included in the IDE. Because the analog pin read values between 0-1023 and the servomotor move between 0-180 , you need to know a new function called map() to change the scale of the values coming from the potentiometer.

For using external libraries you'll first need to import it, with the include keyword.

syntax : #include <libraryname>

Then you must instantiate an object to it.

Syntax: libraryname myObj;

Where libraryname is the name of the library you want to import.
Now you can use the functions included in that library by referring to it by the object that you have created.

The function map() also is interesting:
syntax: int map(int scalNum, int minIn, int maxIn, int minOut, int maxOut)
where scalNum is the number to be scaled, minIn an maxIn are the input range, minOut and maxOut are the output range. It will return the scaled value.
The top photo is the circuit built on the board.

Let me talk about the servomotor included in the box: your servomotor come with female connectors, so you'll need to add header pin to connect it to the bread board. The problem is the fact that the header pin included in my box is a crap, with length of his pin totally "casual".

As you can see the short pins are too short and the long pins are too long, with the result that this things do not fit neither in breadboard nor in the female connector. So I use an homemade solution:

Its not the best things you see, but it works.

As every time, I don't like to follow the project literally, so I added to it something mine.

I use the PWM digital pin to create a visual light sensation of what the servomotor do.

Here the code:

//...other declaration
const int redLedPin = 6;
const int yellowLedPin = 5;
const int greenLedPin = 3;
int redValue = 0;
int greenValue = 0;
int yellowValue = 0; 

void setup(){
//...rest of the code
pinMode(greenLedPin,OUTPUT);
pinMode(yellowLedPin,OUTPUT);
pinMode(redLedPin,OUTPUT);
//...rest of the code
}

void loop() {
//...rest of the code
redValue = map(potVal, 0,1023,0,255);
if (potVal<683) {
  redValue = 0;
  yellowValue = map(potVal, 0,682,0,255);
  if (potVal<342) {
    redValue = 0;
    yellowValue = 0;
    greenValue = map(potVal,0,341,0,255);
  }else {
    greenValue = 255;
  }
} else {
  yellowValue = 255;
  greenValue = 255;
}
analogWrite(redLedPin, redValue);
analogWrite(yellowLedPin, yellowValue);
analogWrite(greenLedPin, greenValue);
//...rest of the code
}

The result is this: 

As you can see from this photo, from how I write, I could be a doctor!

Next post in next days.

Ygy Freezone.

Arduino Starter Kit - Chapter 04 Color Mixing Lamp

New day new race, today I will talk about the fourth chapter of the manual of Arduino Starter Kit:

04 COLOR MIXING LAMP produce any color with a lamp that uses light as an input

In this chapter they present a technique called Pulse Width Modulation (PWM): Since Arduino can't vary the output voltage on its pins, it can only output 5V. Hence you'll need to use the PWM to fade LEDs. PWM rapidly turns the output pin high and low over a fixed periods of time.
When you're rapidly turning the pin high and low, it's as if you were changing the voltage.
The percentage of time a pin is high is called Duty-Cycle.

The Arduino Uno has six pin aside for the PWM (Digital pin 3,5,6,9,10,11) they can identified by the ~ next to their number on the board.

The Circuit:

The function to change the LED's brightness via PWM is called analogWrite()

Syntax: analogWrite(pin,rangeOut)

Where pin is the number of the PWM pin used, and rangeOut is a value between 0 and 255.

NB: analogRead function, as we see in the previous post, return a value between 0-1023, so to use this value you need to convert it into a value between 0-255 dividing it by 4.

As ever if you want the full code, open the IDE and search in the example, is included in the starter kit section.

The result of this project is the top photo, I'm lazy so I don't turn off the light in my room, and the LED is almost ever on. If you cover one or more sensor the light of the RGB change color.

Variant:

In some non official kit there is no RGB LED inside but this project is still present inside the manual.

You can do it anyway, just change the RGB LED with 3 normal color led (1 redLEd, 1 greenLED, 1 blueLED), as described in the following schema:

The result of this little variation is this:

Next post Monday.
See ya.
Ygy Freezone

Arduino Starter Kit - Chapter 3 Love-o-Meter

Hello I'm YGY and this And This is Jackass the third post about the Arduino Starter Kit. Today I'll try to explain the third chapter of the manual:

03 LOVE-O-METER measure how hot-blooded you are

Before you really think I'm retarded you must know that this stupid name come directly from the author of the manual, they try to sell this kit also to the school, and reading this name makes me think that they never go to school.

Here a rare image of some teenager studying and working at school with this kit:

Back to the explanation, in this chapter they introduce the analog sensors and analog pin of the Arduino Uno board.
Arduino has a Analog-to-Digital Converter (ADC) built in, and pin from A0 to A5 are analogics and can report back a value between 0 and 1023, which maps a range from 0V to 5V.

The analogic sensor you'll use for this project is a temperature sensor, more precisely an TMP36 by Analog Device , pay attention to the datasheet when you built the circuit, because if you "invert" the sensor you can have a bad time, like me (thus explaining the picture at the top) because I invert the ground and the 5V of the sensor and when I try the project I literally burn my finger, I'm stupid I know now go further.

Another thing you must know before start to play with analog sensor is the fact which in the Arduino's IDE there is a tool called "Serial Monitor" that enables you to report back result from the microcontroller.

In picture above: the red square is the button to open Serial Monitor. 

In the picture below the schema of the circuit.

As you can see, slowly I'm learning how to use EAGLE.

In the code section in this chapter they introduce some command for interact with analog pin:

Serial.begin(), analogRead(), Serial.print() and Serial.println().

Serial.begin() open a connection between the Arduino and the computer, so you can see the value from analog input on Serial Monitor.

Syntax: Serial.begin(bitxSec)

Where bitxSex is the speed in bit per second at which Arduino will communicate, 9600 is the standard, you can see this speed on the Serial Monitor.

analogRead() is a function to get the value from the analog pin. It return an int value.

Syntax: int analogRead(pin)

Where pin is the number of the analog pin which you want read.

Serial.print() and Serial.println() send informations from the arduino to a connected computer, that you can see into its Serial Monitor.

Syntax: Serial.print(char str) / Serial.println(char str)

Where str is the information you'll print on the Serial Monitor, the difference between print() and println() is only the fact that the second after print on the Serial Monitor go to a new line, instead print continue on the same line.

I lightly modified this project, adding a button which, when pressed, recalibrate the sensor.
In the code you must instantiate the button as INPUT in the setup() function.
In the loop() function you must read from this pin, digitalRead() , if the value is HIGH you recalibrate.
For recalibrating in the Arduino site there is a tutorial, I use something similar:

  switchState = digitalRead(5);

  if (switchState == HIGH) {
    //the button is pressed, resetting the value of the baseline.
    actualTemp = (((analogRead(sensorPin)/1024.0) * 5.0) - .5) * 100;    //calc the temp
    Serial.print("ActualTemp after pressing button: ");
    Serial.println(actualTemp);
 
    if (actualTemp > baselineTemp) {
      actualTemp = baselineTemp;
    }
  } 

The formula for calculate the temp from the sensor value come from the Manual, but if you really feel skilled you can obtain by yourself from the datasheet of the component.

well, for today it's over. Sorry no pic of the board this time.

Ygy Freezone

Arduino Starter Kit - First two chapter

Today I explain you what you can expect from the first two chapter of the manual:

01 GET TO KNOW YOUR TOOLS an introduction to the concepts you'll need to use this kit
02 SPACESHIP INTERFACE design to control panel for your startship

01 GET TO KNOW YOUR TOOLS
The first chapter actually is not a proper Arduino project, instead in this chapter the authors try to introduce the world of electronic at those who not know nothing (or almost) about it.
So they introduce the concept of Series/Parallel and the Ohm's Law for calculate the current of you circuit.

This project divide it self in 4 little, microscopic, project: In the first, as you can see in the schema above, you will simply connect put in series a LED and a 220Ω (ohm) resistor. Arduino board in this case is used only as power source.

The second improve the first, adding a pushbutton between LED and resistor.
Here you can see the magic: The LED do not light until you press the button! And when you release the button the LED turn it off again! Magic, it's magic for sure...

In this rare picture you can see me do the MAGIC.

The third project explain how work two button in series, when you press only one the led do not turn on, when istead you press both button the led, like magic, turn it on. Magically magic.

The fourth, and the last of the first chapter, demonstrate how work two button in parallel. When you press either of two button the led turn it on. Enlightening.
The chapter end with an explanation of the Ohm's Law (V = A*Ω).

02 SPACESHIP INTERFACE
Ok now we know the basic of electronic, why do not try to do something more complex?
In the beginning here they give us an, IMHO, important tip: Since pin 0 and 1 are used for communicating with the computer it is best to start with pin 2.

The Code: the full code for reprogramming our board is already included inside the IDE under "Examples->10.Starter Kit-> p02_SpaceShipInterface" , but I think that writing the code by yourself is really really better considered the fact that you buy this kit for learning how to program and use Arduino.
First of all: Every Arduino program has two main function: setup() and loop(). These function need to be declared.
The setup() run once, when the Arduino is first powered on.
A function named pinMode() is needed for configure the digital pins.
Syntax: pinMode(pinNumber,IOType)
Where pinNumber is the number of the pin which you need to configure, these number are printed on the board; IOType is the type of Input/Output you want give to the pin, the accepted value are INPUT and OUTPUT , both written upper case. Be carefull : Arduino code is case sensitive.

The loop(), instead, runs continuosly after setup() has completed.
To check the voltage level use function digitalRead()
Syntax:digitalRead(pinToRead)
where pinToRead is the number of the pin as explained before.
To sent a value to the output-pin use function digitalWrite()
Syntax: digitalWrite(pin,voltLev)
pin is the number of the output-pin, voltLev can be only HIGH or LOW , which mean 1 or 0.
Another function introducted in this chapter is the delay(), which let you stop the arduino from executing anything for the period of time indicate.
Syntax: delay(mmSec)
Where mmSec is the number of millisecond you want wait.

In the original code they simply put an if/else block and when you press the button the last two led turn on once then turn off again. I think can be more nice adding an for loop block into the else block, and do more cicle of on/off to the led.

The result of this last project is the photo at the top of this post.

Ok, next post in the next days.
If you want know how I draw the schematics, I use EAGLE software with Adafruit library for arduino.

end of transmission...
Ygy Freezone

Arduino Starter Kit - Begin the journey in the microcontroller world

Here we are, the Starter Kit of Arduino is arrived today, and I decide to post a little explanation of every single project included in this box.
In the next days and weeks I'll follow this list of small projects and I'll do some post with some shit like photo/video and my impressions, everyone of these projects is from the book included in the kit (Arduino Projects Book):

01 GET TO KNOW YOUR TOOLS an introduction to the concepts you'll need to use this kit
02 SPACESHIP INTERFACE design to control panel for your startship
03 LOVE-O-METER measure how hot-blooded you are
04 COLOR MIXING LAMP produce any color with a lamp that uses light as an input
05 MOOD CUE clue people in to how you're doing
06 LIGHT THEREMIN create a musical instrument you play by waving your hands
07 KEYBOARD INSTRUMENT play music and make some noise with this keyboard
08 DIGITAL HOURGLASS a light-up hourglass that can stop you from working too much
09 MOTORIZED PINWHEEL a color wheel that will have your head spinning
10 ZOETROPE create a mechanical animation you can play forward or reverse
11 CRYSTAL BALL a mystical tour to answer all your tough question
12 KNOCK LOCK tap out the secret code to open the door
13 TOUCHY-FEEL LAMP a lamp that responds to your touch
14 TWEAK THE ARDUINO LOGO control your personal computer from your Arduino
15 HACKING BUTTONS create a master control for all your devices!

Inside the box there are some standard elettronic components, here the list directly from the Arduino website:

1 Arduino Projects Book (170 pages)
1 Arduino UNO board rev.3
1 USB cable
1 Breadboard
1 Easy-to-assemble wooden base
1 9v battery snap
70 Solid core jumper wires
2 Stranded jumper wires
6 Photoresistor [VT90N2 LDR]
3 Potentiometer 10kilohm
10 Pushbuttons
1 Temperature sensor [TMP36]
1 Tilt sensor
1 alphanumeric LCD (16x2 characters)
1 LED (bright white)
1 LED (RGB)
8 LEDs (red)
8 LEDs (green)
8 LEDs (yellow)
3 LEDs (blue)
1 Small DC motor 6/9V
1 Small servo motor
1 Piezo capsule [PKM17EPP-4001-B0]
1 H-bridge motor driver [L293D]
2 Optocouplers [4N35]
5 Transistor [BC547]
2 Mosfet transistors [IRF520]
5 Capacitors 100nF
3 Capacitors 100uF
5 Capacitor 100pF
5 Diodes [1N4007]
3 Transparent gels (red, green, blue)
1 Male pins strip (40x1)
20 Resistors 220 ohm
5 Resistors 560 ohm
5 Resistors 1 kilohm
5 Resistors 4.7 kilohm
20 Resistors 10 kilohm
5 Resistors 1 megohm
5 Resistors 10 megohm

Today I only built the wooden base, in which you must screw the arduino board to it, and there is immediately a problem: they do not include in the box the 3 screws needed for this passage.
Luckily I used to built all my PCs, so I have a lot of little screw and screw pins and I used some of it for the Arduino board but they don't fit perfectly: as you can see in the next photos, I don't put a screw in the hole close to power input, this because the screw simply do not enter without touching the power input, so I decide to not put this screw. I hope to not burn everything on the first lighting, but I'm pretty sure there will be no problem because no internal connection was even close to the screw hole.

EDIT: I found the lost screw (they was in the box of electrical component, my fault), so I mount the wooden base with the screw included in the kit.


This is my first try in this world, and while I believe this is only the beginning of a series of post every time more complexes (I have in mind some project, that i will document here when I can begin to do it), don't blame me for the stupid thing that I post in this first series of article in the Arduino World, more smarts and complexes things come early... or not, I don't know and I can't see the future, maybe tomorrow I'll die in this case no more post i think.

Let's go, it's time to start to hack my world...
Ygy Freezone.