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/* =================================================================================================
      Project: Arduino Heart rate monitor
       Author: Scott C
      Created: 21st April 2015
  Arduino IDE: 1.6.2
      Website: http://arduinobasics.blogspot.com/p/arduino-basics-projects-page.html
  Description: This is a simple sketch that uses a Grove Ear-clip Heart Rate sensor attached to an Arduino UNO,
               which sends heart rate data to the computer via Serial communication. You can see the raw data
               using the Serial monitor on the Arduino IDE, however, this sketch was specifically
               designed to interface with the matching Processing sketch for a much nicer graphical display.
               NO LIBRARIES REQUIRED.
=================================================================================================== */

#define Heart 2                            //Attach the Grove Ear-clip sensor to digital pin 2.
#define LED 4                              //Attach an LED to digital pin 4

boolean beat = false;                      /* This "beat" variable is used to control the timing of the Serial communication
                                           so that data is only sent when there is a "change" in digital readings. */

//==SETUP==========================================================================================
void setup() {
  Serial.begin(9600);                     //Initialise serial communication
  pinMode(Heart, INPUT);                  //Set digital pin 2 (heart rate sensor pin) as an INPUT
  pinMode(LED, OUTPUT);                   //Set digital pin 4 (LED) to an OUTPUT
}


//==LOOP============================================================================================
void loop() {
  if(digitalRead(Heart)>0){               //The heart rate sensor will trigger HIGH when there is a heart beat
    if<!beat){><span>//Only send data when it first discovers a heart beat - otherwise it will send a high value multiple times</span><br  />      beat=<span>true</span>;                          <span>//By changing the beat variable to true, it stops further transmissions of the high signal</span><br  />      <span>digitalWrite</span>(LED, <span>HIGH</span>);            <span>//Turn the LED on </span><br  />      <span><b>Serial</b></span>.<span>println</span>(1023);               <span>//Send the high value to the computer via Serial communication.</span><br  />    }<br  />  } <span>else</span> {                                <span>//If the reading is LOW, </span><br  />    <span>if</span>(beat){                             <span>//and if this has just changed from HIGH to LOW (first low reading)</span><br  />      beat=<span>false</span>;                         <span>//change the beat variable to false (to stop multiple transmissions)</span><br  />      <span>digitalWrite</span>(LED, <span>LOW</span>);             <span>//Turn the LED off.</span><br  />      <span><b>Serial</b></span>.<span>println</span>(0);                  <span>//then send a low value to the computer via Serial communication.</span><br  />    }<br  />  }<br  />}</pre> </td> </tr> </table></div></p> <br  />   <br  />   <br  />   <br  />   <p> <h4><a href="https://processing.org/download/?processing">Processing Sketch</a></h4> <br  />    <div> <table> <tr> <td> <pre>  1<br  />  2<br  />  3<br  />  4<br  />  5<br  />  6<br  />  7<br  />  8<br  />  9<br  /> 10<br  /> 11<br  /> 12<br  /> 13<br  /> 14<br  /> 15<br  /> 16<br  /> 17<br  /> 18<br  /> 19<br  /> 20<br  /> 21<br  /> 22<br  /> 23<br  /> 24<br  /> 25<br  /> 26<br  /> 27<br  /> 28<br  /> 29<br  /> 30<br  /> 31<br  /> 32<br  /> 33<br  /> 34<br  /> 35<br  /> 36<br  /> 37<br  /> 38<br  /> 39<br  /> 40<br  /> 41<br  /> 42<br  /> 43<br  /> 44<br  /> 45<br  /> 46<br  /> 47<br  /> 48<br  /> 49<br  /> 50<br  /> 51<br  /> 52<br  /> 53<br  /> 54<br  /> 55<br  /> 56<br  /> 57<br  /> 58<br  /> 59<br  /> 60<br  /> 61<br  /> 62<br  /> 63<br  /> 64<br  /> 65<br  /> 66<br  /> 67<br  /> 68<br  /> 69<br  /> 70<br  /> 71<br  /> 72<br  /> 73<br  /> 74<br  /> 75<br  /> 76<br  /> 77<br  /> 78<br  /> 79<br  /> 80<br  /> 81<br  /> 82<br  /> 83<br  /> 84<br  /> 85<br  /> 86<br  /> 87<br  /> 88<br  /> 89<br  /> 90<br  /> 91<br  /> 92<br  /> 93<br  /> 94<br  /> 95<br  /> 96<br  /> 97<br  /> 98<br  /> 99<br  />100<br  />101<br  />102<br  />103<br  />104<br  />105<br  />106<br  />107<br  />108<br  />109<br  />110<br  />111<br  />112<br  />113<br  />114<br  />115<br  />116<br  />117<br  />118<br  />119<br  />120<br  />121<br  />122<br  />123<br  />124<br  />125<br  />126<br  />127<br  />128<br  />129<br  />130<br  />131<br  />132<br  />133<br  />134<br  />135<br  />136<br  />137<br  />138<br  />139<br  />140<br  />141<br  />142<br  />143<br  />144<br  />145<br  />146<br  />147<br  />148<br  />149<br  />150<br  />151<br  />152<br  />153<br  />154<br  />155<br  />156<br  />157<br  />158<br  />159<br  />160<br  />161<br  />162<br  />163<br  />164<br  />165<br  />166<br  />167<br  />168<br  />169<br  />170<br  />171<br  />172<br  />173<br  />174<br  />175<br  />176<br  />177<br  />178<br  />179<br  />180<br  />181<br  />182<br  />183<br  />184<br  />185<br  />186<br  />187<br  />188<br  />189<br  />190<br  />191<br  />192<br  />193<br  />194<br  />195<br  />196<br  />197<br  />198<br  />199<br  />200<br  />201<br  />202<br  />203<br  />204<br  />205<br  />206<br  />207<br  />208<br  />209<br  />210<br  />211<br  />212<br  />213<br  />214<br  /></pre> </td> <td> <pre><br  /><span>/* =================================================================================================</span><br  /><span>       Project: Arduino Heart rate monitor</span><br  /><span>        Author: Scott C</span><br  /><span>       Created: 21st April 2015</span><br  /><span>Processing IDE: 2.2.1</span><br  /><span>       Website: http://arduinobasics.blogspot.com/p/arduino-basics-projects-page.html</span><br  /><span>   Description: A Grove Ear-clip heart rate sensor allows an Arduino UNO to sense your pulse.</span><br  /><span>                The data obtained by the Arduino can then be sent to the computer via Serial communication</span><br  /><span>                which is then displayed graphically using this Processing sketch.</span><br  /><span>                </span><br  /><span>=================================================================================================== */</span><br  /><br  /><span>import</span> processing.serial.*;                             <span>// Import the serial library to allow Serial communication with the Arduino</span><br  /><br  /><span>int</span> numOfRecs = 45;                                     <span>//   numOfRecs: The number of rectangles to display across the screen</span><br  />Rectangle[] myRecs = <span>new</span> Rectangle[numOfRecs];          <span>//    myRecs[]: Is the array of Rectangles.  Rectangle is a custom class (programmed within this sketch)</span><br  /><br  />Serial myPort;                                         <br  /><span>String</span> comPortString=<span>"0"</span>;                              <span>//comPortString: Is used to hold the string received from the Arduino</span><br  /><span>float</span> arduinoValue = 0;                                 <span>//arduinoValue: Is the float variable converted from comPortString</span><br  /><span>boolean</span> beat = <span>false</span>;                                   <span>//        beat: Used to control for multiple high/low signals coming from the Arduino</span><br  /><br  /><span>int</span> totalTime = 0;                                      <span>//   totalTime: Is the variable used to identify the total time between beats</span><br  /><span>int</span> lastTime = 0;                                       <span>//    lastTime: Is the variable used to remember when the last beat took place</span><br  /><span>int</span> beatCounter = 0;                                    <span>// beatCounter: Is used to keep track of the number of beats (in order to calculate the average BPM)</span><br  /><span>int</span> totalBeats = 10;                                    <span>//  totalBeats: Tells the computer that we want to calculate the average BPM using 10 beats.</span><br  /><span>int</span>[] BPM = <span>new</span> <span>int</span>[totalBeats];                        <span>//       BPM[]: Is the Beat Per Minute (BPM) array - to hold 10 BPM calculations</span><br  /><span>int</span> sumBPM = 0;                                         <span>//      sumBPM: Is used to sum the BPM[] array values, and is then used to calculate the average BPM.</span><br  /><span>int</span> avgBPM = 0;                                         <span>//      avgBPM: Is the variable used to hold the average BPM calculated value.</span><br  /><br  /><span>PFont</span> f, f2;                                            <span>//     f & f2 : Are font related variables. Used to store font properties. </span><br  /><br  /><br  /><span>//==SETUP==============================================================================================</span><br  /><span>void</span> <span><b>setup</b></span>(){<br  />  <span>size</span>(<span>displayWidth</span>,<span>displayHeight</span>);                     <span>// Set the size of the display to match the monitor width and height</span><br  />  <span>smooth</span>();                                             <span>// Draw all shapes with smooth edges.</span><br  />  f = <span>createFont</span>(<span>"Arial"</span>,24);                           <span>// Initialise the "f" font variable    - used for the "calibrating" text displayed at the beginning</span><br  />  f2 = <span>createFont</span>(<span>"Arial"</span>,96);                          <span>// Initialise the "f2" font variable   - used for the avgBPM display on screen</span><br  />  <br  />  <span>for</span>(<span>int</span> i=0; i<numOfRecs; i++){                       <span>// Initialise the array of rectangles</span><br  />    myRecs[i] = <span>new</span> Rectangle(i, numOfRecs);<br  />  }<br  />  <br  />  <span>for</span>(<span>int</span> i=0; i<totalBeats; i++){                      <span>// Initialise the BPM array</span><br  />    BPM[i] = 0;<br  />  }<br  />  <br  />  myPort = <span>new</span> Serial(<span>this</span>, Serial.<span>list</span>()[0], 9600);    <span>// Start Serial communication with the Arduino using a baud rate of 9600</span><br  />  myPort.bufferUntil(<span>'\n'</span>);                             <span>// Trigger a SerialEvent on new line</span><br  />}<br  /><br  /><br  /><span>//==DRAW==============================================================================================</span><br  /><span>void</span> <span><b>draw</b></span>(){<br  />  <span>background</span>(0);                                        <span>// Set the background to BLACK (this clears the screen each time)</span><br  />  drawRecs();                                           <span>// Method call to draw the rectangles on the screen</span><br  />  drawBPM();                                            <span>// Method call to draw the avgBPM value to the top right of the screen</span><br  />}<br  /><br  /><br  /><span>//==drawRecs==========================================================================================</span><br  /><span>void</span> drawRecs(){                                        <span>// This custom method will draw the rectangles on the screen                                </span><br  />  myRecs[0].setSize(arduinoValue);                      <span>// Set the first rectangle to match arduinoValue; any positive value will start the animation.</span><br  />  <span>for</span>(<span>int</span> i=numOfRecs-1; i>0; i--){                     <span>// The loop counts backwards for coding efficiency - and is used to draw all of the rectangles to screen</span><br  />    myRecs[i].setMult(i);                               <span>// setMulti creates the specific curve pattern. </span><br  />    myRecs[i].setRed(avgBPM);                           <span>// The rectangles become more "Red" with higher avgBPM values</span><br  />    myRecs[i].setSize(myRecs[i-1].getH());              <span>// The current rectangle size is determined by the height of the rectangle immediately to it's left</span><br  />    <span>fill</span>(myRecs[i].getR(),myRecs[i].getG(), myRecs[i].getB());                     <span>// Set the colour of this rectangle</span><br  />    <span>rect</span>(myRecs[i].getX(), myRecs[i].getY(), myRecs[i].getW(), myRecs[i].getH());  <span>// Draw this rectangle</span><br  />  }<br  />}<br  /><br  /><br  /><span>//==drawBPM===========================================================================================</span><br  /><span>void</span> drawBPM(){                                         <span>// This custom method is used to calculate the avgBPM and draw it to screen.</span><br  />  sumBPM = 0;                                           <span>// Reset the sumBPM variable</span><br  />  avgBPM = 0;                                           <span>// Reset the avgBPM variable</span><br  />  <span>boolean</span> calibrating = <span>false</span>;                          <span>// calibrating: this boolean variable is used to control when the avgBPM is displayed to screen</span><br  />  <br  />  <span>for</span>(<span>int</span> i=1; i<totalBeats; i++){<br  />    sumBPM = sumBPM + BPM[i-1];                         <span>// Sum all of the BPM values in the BPM array.</span><br  />    <span>if</span>(BPM[i-1]<1){                                     <span>// If any BPM values are equal to 0, then set the calibrating variable to true. </span><br  />      calibrating = <span>true</span>;                               <span>// This will be used later to display "calibrating" on the screen.</span><br  />    }<br  />  }<br  />  avgBPM = sumBPM/(totalBeats-1);                       <span>// Calculate the average BPM from all BPM values</span><br  />                                                        <br  />  <span>fill</span>(255);                                            <span>// The text will be displayed as WHITE text</span><br  />  <span>if</span>(calibrating){<br  />    <span>textFont</span>(f);<br  />    <span>text</span>(<span>"Calibrating"</span>, (4*<span>width</span>)/5, (<span>height</span>/5));      <span>// If the calibrating variable is TRUE, then display the word "Calibrating" on screen</span><br  />    <span>fill</span>(0);                                           <span>// Change the fill and stroke to black (0) so that other text is "hidden" while calibrating variable is TRUE</span><br  />    <span>stroke</span>(0);<br  />  } <span>else</span> {<br  />    <span>textFont</span>(f2);<br  />    <span>text</span>(avgBPM, (4*<span>width</span>)/5, (<span>height</span>/5));             <span>// If the calibrating variable is FALSE, then display the avgBPM variable on screen</span><br  />    <span>stroke</span>(255);                                       <span>// Change the stroke to white (255) to show the white line underlying the word BPM.</span><br  />  }<br  />  <br  />   <span>textFont</span>(f);<br  />   <span>text</span>(<span>"BPM"</span>, (82*<span>width</span>)/100, (<span>height</span>/11));           <span>// This will display the underlined word "BPM" when calibrating variable is FALSE.</span><br  />   <span>line</span>((80*<span>width</span>)/100, (<span>height</span>/10),(88*<span>width</span>)/100, (<span>height</span>/10));<br  />   <span>stroke</span>(0);<br  />}<br  /><br  /><br  /><span>//==serialEvent===========================================================================================</span><br  /><span>void</span> serialEvent(Serial cPort){                        <span>// This will be triggered every time a "new line" of data is received from the Arduino</span><br  /> comPortString = cPort.readStringUntil(<span>'\n'</span>);          <span>// Read this data into the comPortString variable.</span><br  /> <span>if</span>(comPortString != <span>null</span>) {                           <span>// If the comPortString variable is not NULL then</span><br  />   comPortString=<span>trim</span>(comPortString);                  <span>// trim any white space around the text.</span><br  />   <span>int</span> i = <span>int</span>(<span>map</span>(<span>Integer</span>.<span>parseInt</span>(comPortString),1,1023,1,<span>height</span>));  <span>// convert the string to an integer, and map the value so that the rectangle will fit within the screen.</span><br  />   arduinoValue = <span>float</span>(i);                            <span>// Convert the integer into a float value.</span><br  />   <span>if</span> (!beat){<br  />     <span>if</span>(arduinoValue>0){                               <span>// When a beat is detected, the "trigger" method is called.</span><br  />       trigger(<span>millis</span>());                              <span>// millis() creates a timeStamp of when the beat occured.</span><br  />       beat=<span>true</span>;                                      <span>// The beat variable is changed to TRUE to register that a beat has been detected.</span><br  />     }<br  />   }<br  />   <span>if</span> (arduinoValue<1){                                <span>// When the Arduino value returns back to zero, we will need to change the beat status to FALSE.</span><br  />     beat = <span>false</span>;<br  />   }<br  /> }<br  />} <br  /><br  /><br  /><span>//==trigger===========================================================================================</span><br  /><span>void</span> trigger(<span>int</span> time){                                <span>// This method is used to calculate the Beats per Minute (BPM) and to store the last 10 BPMs into the BPM[] array.</span><br  />  totalTime = time - lastTime;                         <span>// totalTime = the current beat time minus the last time there was a beat.</span><br  />  lastTime = time;                                     <span>// Set the lastTime variable to the current "time" for the next round of calculations.</span><br  />  BPM[beatCounter] = 60000/totalTime;                  <span>// Calculate BPM from the totalTime. 60000 = 1 minute.</span><br  />  beatCounter++;                                       <span>// Increment the beatCounter </span><br  />  <span>if</span> (beatCounter>totalBeats-1){                       <span>// Reset the beatCounter when the total number of BPMs have been stored into the BPM[] array.</span><br  />    beatCounter=0;                                     <span>// This allows us to keep the last 10 BPM calculations at all times.</span><br  />  }<br  />}<br  /><br  /><br  /><span>//==sketchFullScreen==========================================================================================</span><br  /><span>boolean</span> sketchFullScreen() {                           <span>// This puts Processing into Full Screen Mode</span><br  /> <span>return</span> <span>true</span>;<br  />}<br  /><br  /><br  /><span>//==Rectangle CLASS==================================================================================*********</span><br  /><span>class</span> Rectangle{<br  />  <span>float</span> xPos, defaultY, yPos, myWidth, myHeight, myMultiplier;    <span>// Variables used for drawing rectangles</span><br  />  <span>int</span> blueVal, greenVal, redVal;                                  <span>// Variables used for the rectangle colour</span><br  />  <br  />  Rectangle(<span>int</span> recNum, <span>int</span> nRecs){                               <span>// The rectangles are constructed using two variables. The total number of rectangles to be displayed, and the identification of this rectangle (recNum)</span><br  />    myWidth = <span>displayWidth</span>/nRecs;                                 <span>// The width of the rectangle is determined by the screen width and the total number of rectangles.</span><br  />    xPos = recNum * myWidth;                                      <span>// The x Position of this rectangle is determined by the width of the rectangles (all same) and the rectangle identifier.</span><br  />    defaultY=<span>displayHeight</span>/2;                                     <span>// The default Y position of the rectangle is half way down the screen.</span><br  />    yPos = defaultY;                                              <span>// yPos is used to adjust the position of the rectangle as the size changes.</span><br  />    myHeight = 1;                                                 <span>// The height of the rectangle starts at 1 pixel</span><br  />    myMultiplier = 1;                                             <span>// The myMultiplier variable will be used to create the funnel shaped path for the rectangles.</span><br  />    redVal = 0;                                                   <span>// The red Value starts off being 0 - but changes with avgBPM. Higher avgBPM means higher redVal</span><br  />    <br  />    <span>if</span> (recNum>0){                                                <span>// The blue Value progressively increases with every rectangle (moving to the right of the screen)</span><br  />      blueVal = (recNum*255)/nRecs;<br  />    } <span>else</span> {<br  />      blueVal = 0;<br  />    }<br  />    greenVal = 255-blueVal;                                       <span>// Initially, the green value is at the opposite end of the spectrum to the blue value.</span><br  />  }<br  />  <br  />  <span>void</span> setSize(<span>float</span> newSize){                                    <span>// This is used to set the new size of each rectangle </span><br  />    myHeight=newSize*myMultiplier;<br  />    yPos=defaultY-(newSize/2);<br  />  }<br  />  <br  />  <span>void</span> setMult(<span>int</span> i){                                            <span>// The multiplier is a function of COS, which means that it varies from 1 to 0.</span><br  />    myMultiplier = <span>cos</span>(<span>radians</span>(i));                               <span>// You can try other functions to experience different effects.</span><br  />  }<br  />  <br  />  <span>void</span> setRed(<span>int</span> r){<br  />    redVal = <span>int</span>(<span>constrain</span>(<span>map</span>(<span>float</span>(r), 60, 100, 0, 255),0,255)); <span>// setRed is used to change the redValue based on the "normal" value for resting BPM (60-100). </span><br  />    greenVal = 255 - redVal;                                       <span>// When the avgBPM > 100, redVal will equal 255, and the greenVal will equal 0.</span><br  />  }                                                                <span>// When the avgBPM < 60, redVal will equal 0, and greenVal will equal 255.</span><br  />  <br  />  <span>float</span>  getX(){                                                   <span>// get the x Position of the rectangle</span><br  />    <span>return</span> xPos;<br  />  }<br  /> <br  />  <span>float</span> getY(){                                                    <span>// get the y Position of the rectangle</span><br  />    <span>return</span> yPos;<br  />  }<br  />  <br  />  <span>float</span> getW(){                                                    <span>// get the width of the rectangle</span><br  />    <span>return</span> myWidth;<br  />  }<br  />  <br  />  <span>float</span> getH(){                                                    <span>// get the height of the rectangle</span><br  />    <span>return</span> myHeight;<br  />  }<br  />  <br  />  <span>float</span> getM(){                                                    <span>// get the Multiplier of the rectangle</span><br  />    <span>return</span> myMultiplier;<br  />  }<br  />  <br  />  <span>int</span> getB(){                                                      <span>// get the "blue" component of the rectangle colour</span><br  />    <span>return</span> blueVal;<br  />  }<br  />  <br  />  <span>int</span> getR(){                                                      <span>// get the "red" component of the rectangle colour</span><br  />    <span>return</span> redVal;<br  />  }<br  />  <br  />  <span>int</span> getG(){                                                      <span>// get the "green" component of the rectangle colour</span><br  />    <span>return</span> greenVal;<br  />  }<br  />}<br  /><br  /></pre> </td> </tr> </table></div></p> <br  />   <br  /> <p> <h4>Processing Code Discussion:</h4><br  /> </p><p>       The Rectangle class was created to store relevant information about each rectangle.        By using a custom class, we were able to design our rectangles any way we wanted.        These rectangles have properties and methods which allow us to easily control their        position, size and colour. By adding some smart functionality to each rectangle, we were able to get the rectangle to automatically        position and colour itself based on key values. </p> <p>        The Serial library is used to allow communication with the Arduino. In this Processing sketch, the values obtained from the Arduino         were converted to floats to allow easy calulations of the beats per minute (BPM).         I am aware that I have over-engineered the serialEvent method somewhat, because the Arduino         is only really sending two values. I didn't really need to convert the String. But I am happy with         the end result, and it does the job I needed it to...        </p> <div> <p> <div> <a href="http://4.bp.blogspot.com/-EVTCQ3vkgGc/VTnOarlOWSI/AAAAAAAABdc/MslEU5oirAY/s1600/Complete%2BWorkstation2.jpg"><img src="http://4.bp.blogspot.com/-EVTCQ3vkgGc/VTnOarlOWSI/AAAAAAAABdc/MslEU5oirAY/s1600/Complete%2BWorkstation2.jpg"  /> </a> </div> </p> </div> </div><!--separator --><img src="https://images-blogger-opensocial.googleusercontent.com/gadgets/proxy?url=http%3A%2F%2F1.bp.blogspot.com%2F-XQiwNpdqOxk%2FT_rKCzDh4nI%2FAAAAAAAAAQY%2FOfYBljhU6Lk%2Fs1600%2FSeparator.jpg&container=blogger&gadget=a&rewriteMime=image%2F*"  /><br  /><p> <div>     This project is quite simple. I designed it so that you could omit the Processing code if you wanted to.      In that scenario, you would only be left with a blinking LED that blinks in time with your pulse.      The Processing code takes this project to the next level. It provides a nice animation and calculates         the beats per minute (BPM). <br  />           <br  />        I hope you liked this tutorial. Please feel free to share it, comment or give it a plus one.         If you didn't like it, I would still appreciate your constructive feedback.  </div> <br  />   <div> <p> <!--separator --> <img src="https://images-blogger-opensocial.googleusercontent.com/gadgets/proxy?url=http%3A%2F%2F1.bp.blogspot.com%2F-XQiwNpdqOxk%2FT_rKCzDh4nI%2FAAAAAAAAAQY%2FOfYBljhU6Lk%2Fs1600%2FSeparator.jpg&container=blogger&gadget=a&rewriteMime=image%2F*"  /><br  /> <br  /> </p> </div> </p><p> <div>   If you like this page, please do me a favour and show your appreciation : <br  /> <br  />     <br  />   Visit my <a href="https://plus.google.com/u/0/b/107402020974762902161/107402020974762902161/posts">ArduinoBasics Google + page</a>.<br  />   Follow me on Twitter by looking for <a href="https://twitter.com/ArduinoBasics">ScottC @ArduinoBasics</a>.<br  />   I can also be found on <a href="https://www.pinterest.com/ArduinoBasics/">Pinterest</a> and <a href="https://instagram.com/arduinobasics">Instagram</a>. <br  />   Have a look at my videos on my <a href="https://www.youtube.com/user/ScottCMe/videos">YouTube channel</a>.<br  /> </div> </p> <br  />   <br  />   <p> <div> <a href="http://3.bp.blogspot.com/-x_TA-qhOCzM/VTnULXoWhQI/AAAAAAAABds/quh02BWGsec/s1600/Slide1.JPG"><img src="http://3.bp.blogspot.com/-x_TA-qhOCzM/VTnULXoWhQI/AAAAAAAABds/quh02BWGsec/s1600/Slide1.JPG"  /></a></div><br  /> </p> <br  />   <br  />   <br  />   <div> <p> <!--separator --> <img src="https://images-blogger-opensocial.googleusercontent.com/gadgets/proxy?url=http%3A%2F%2F1.bp.blogspot.com%2F-XQiwNpdqOxk%2FT_rKCzDh4nI%2FAAAAAAAAAQY%2FOfYBljhU6Lk%2Fs1600%2FSeparator.jpg&container=blogger&gadget=a&rewriteMime=image%2F*"  /><br  /> <br  /> </p> </div> <p>  However, if you do not have a google profile... <br  />Feel free to share this page with your friends in any way you see fit.  </p>

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/* =================================================================================================
      Project: Arduino Heart rate monitor
       Author: Scott C
      Created: 21st April 2015
  Arduino IDE: 1.6.2
      Website: http://arduinobasics.blogspot.com/p/arduino-basics-projects-page.html
  Description: This is a simple sketch that uses a Grove Ear-clip Heart Rate sensor attached to an Arduino UNO,
               which sends heart rate data to the computer via Serial communication. You can see the raw data
               using the Serial monitor on the Arduino IDE, however, this sketch was specifically
               designed to interface with the matching Processing sketch for a much nicer graphical display.
               NO LIBRARIES REQUIRED.
=================================================================================================== */

#define Heart 2                            //Attach the Grove Ear-clip sensor to digital pin 2.
#define LED 4                              //Attach an LED to digital pin 4

boolean beat = false;                      /* This "beat" variable is used to control the timing of the Serial communication
                                           so that data is only sent when there is a "change" in digital readings. */

//==SETUP==========================================================================================
void setup() {
  Serial.begin(9600);                     //Initialise serial communication
  pinMode(Heart, INPUT);                  //Set digital pin 2 (heart rate sensor pin) as an INPUT
  pinMode(LED, OUTPUT);                   //Set digital pin 4 (LED) to an OUTPUT
}


//==LOOP============================================================================================
void loop() {
  if(digitalRead(Heart)>0){               //The heart rate sensor will trigger HIGH when there is a heart beat
    if<!beat){><span>//Only send data when it first discovers a heart beat - otherwise it will send a high value multiple times</span><br  />      beat=<span>true</span>;                          <span>//By changing the beat variable to true, it stops further transmissions of the high signal</span><br  />      <span>digitalWrite</span>(LED, <span>HIGH</span>);            <span>//Turn the LED on </span><br  />      <span><b>Serial</b></span>.<span>println</span>(1023);               <span>//Send the high value to the computer via Serial communication.</span><br  />    }<br  />  } <span>else</span> {                                <span>//If the reading is LOW, </span><br  />    <span>if</span>(beat){                             <span>//and if this has just changed from HIGH to LOW (first low reading)</span><br  />      beat=<span>false</span>;                         <span>//change the beat variable to false (to stop multiple transmissions)</span><br  />      <span>digitalWrite</span>(LED, <span>LOW</span>);             <span>//Turn the LED off.</span><br  />      <span><b>Serial</b></span>.<span>println</span>(0);                  <span>//then send a low value to the computer via Serial communication.</span><br  />    }<br  />  }<br  />}</pre> </td> </tr> </table></div></p> <br  />   <br  />   <br  />   <br  />   <p> <h4><a href="https://processing.org/download/?processing">Processing Sketch</a></h4> <br  />    <div> <table> <tr> <td> <pre>  1<br  />  2<br  />  3<br  />  4<br  />  5<br  />  6<br  />  7<br  />  8<br  />  9<br  /> 10<br  /> 11<br  /> 12<br  /> 13<br  /> 14<br  /> 15<br  /> 16<br  /> 17<br  /> 18<br  /> 19<br  /> 20<br  /> 21<br  /> 22<br  /> 23<br  /> 24<br  /> 25<br  /> 26<br  /> 27<br  /> 28<br  /> 29<br  /> 30<br  /> 31<br  /> 32<br  /> 33<br  /> 34<br  /> 35<br  /> 36<br  /> 37<br  /> 38<br  /> 39<br  /> 40<br  /> 41<br  /> 42<br  /> 43<br  /> 44<br  /> 45<br  /> 46<br  /> 47<br  /> 48<br  /> 49<br  /> 50<br  /> 51<br  /> 52<br  /> 53<br  /> 54<br  /> 55<br  /> 56<br  /> 57<br  /> 58<br  /> 59<br  /> 60<br  /> 61<br  /> 62<br  /> 63<br  /> 64<br  /> 65<br  /> 66<br  /> 67<br  /> 68<br  /> 69<br  /> 70<br  /> 71<br  /> 72<br  /> 73<br  /> 74<br  /> 75<br  /> 76<br  /> 77<br  /> 78<br  /> 79<br  /> 80<br  /> 81<br  /> 82<br  /> 83<br  /> 84<br  /> 85<br  /> 86<br  /> 87<br  /> 88<br  /> 89<br  /> 90<br  /> 91<br  /> 92<br  /> 93<br  /> 94<br  /> 95<br  /> 96<br  /> 97<br  /> 98<br  /> 99<br  />100<br  />101<br  />102<br  />103<br  />104<br  />105<br  />106<br  />107<br  />108<br  />109<br  />110<br  />111<br  />112<br  />113<br  />114<br  />115<br  />116<br  />117<br  />118<br  />119<br  />120<br  />121<br  />122<br  />123<br  />124<br  />125<br  />126<br  />127<br  />128<br  />129<br  />130<br  />131<br  />132<br  />133<br  />134<br  />135<br  />136<br  />137<br  />138<br  />139<br  />140<br  />141<br  />142<br  />143<br  />144<br  />145<br  />146<br  />147<br  />148<br  />149<br  />150<br  />151<br  />152<br  />153<br  />154<br  />155<br  />156<br  />157<br  />158<br  />159<br  />160<br  />161<br  />162<br  />163<br  />164<br  />165<br  />166<br  />167<br  />168<br  />169<br  />170<br  />171<br  />172<br  />173<br  />174<br  />175<br  />176<br  />177<br  />178<br  />179<br  />180<br  />181<br  />182<br  />183<br  />184<br  />185<br  />186<br  />187<br  />188<br  />189<br  />190<br  />191<br  />192<br  />193<br  />194<br  />195<br  />196<br  />197<br  />198<br  />199<br  />200<br  />201<br  />202<br  />203<br  />204<br  />205<br  />206<br  />207<br  />208<br  />209<br  />210<br  />211<br  />212<br  />213<br  />214<br  /></pre> </td> <td> <pre><br  /><span>/* =================================================================================================</span><br  /><span>       Project: Arduino Heart rate monitor</span><br  /><span>        Author: Scott C</span><br  /><span>       Created: 21st April 2015</span><br  /><span>Processing IDE: 2.2.1</span><br  /><span>       Website: http://arduinobasics.blogspot.com/p/arduino-basics-projects-page.html</span><br  /><span>   Description: A Grove Ear-clip heart rate sensor allows an Arduino UNO to sense your pulse.</span><br  /><span>                The data obtained by the Arduino can then be sent to the computer via Serial communication</span><br  /><span>                which is then displayed graphically using this Processing sketch.</span><br  /><span>                </span><br  /><span>=================================================================================================== */</span><br  /><br  /><span>import</span> processing.serial.*;                             <span>// Import the serial library to allow Serial communication with the Arduino</span><br  /><br  /><span>int</span> numOfRecs = 45;                                     <span>//   numOfRecs: The number of rectangles to display across the screen</span><br  />Rectangle[] myRecs = <span>new</span> Rectangle[numOfRecs];          <span>//    myRecs[]: Is the array of Rectangles.  Rectangle is a custom class (programmed within this sketch)</span><br  /><br  />Serial myPort;                                         <br  /><span>String</span> comPortString=<span>"0"</span>;                              <span>//comPortString: Is used to hold the string received from the Arduino</span><br  /><span>float</span> arduinoValue = 0;                                 <span>//arduinoValue: Is the float variable converted from comPortString</span><br  /><span>boolean</span> beat = <span>false</span>;                                   <span>//        beat: Used to control for multiple high/low signals coming from the Arduino</span><br  /><br  /><span>int</span> totalTime = 0;                                      <span>//   totalTime: Is the variable used to identify the total time between beats</span><br  /><span>int</span> lastTime = 0;                                       <span>//    lastTime: Is the variable used to remember when the last beat took place</span><br  /><span>int</span> beatCounter = 0;                                    <span>// beatCounter: Is used to keep track of the number of beats (in order to calculate the average BPM)</span><br  /><span>int</span> totalBeats = 10;                                    <span>//  totalBeats: Tells the computer that we want to calculate the average BPM using 10 beats.</span><br  /><span>int</span>[] BPM = <span>new</span> <span>int</span>[totalBeats];                        <span>//       BPM[]: Is the Beat Per Minute (BPM) array - to hold 10 BPM calculations</span><br  /><span>int</span> sumBPM = 0;                                         <span>//      sumBPM: Is used to sum the BPM[] array values, and is then used to calculate the average BPM.</span><br  /><span>int</span> avgBPM = 0;                                         <span>//      avgBPM: Is the variable used to hold the average BPM calculated value.</span><br  /><br  /><span>PFont</span> f, f2;                                            <span>//     f & f2 : Are font related variables. Used to store font properties. </span><br  /><br  /><br  /><span>//==SETUP==============================================================================================</span><br  /><span>void</span> <span><b>setup</b></span>(){<br  />  <span>size</span>(<span>displayWidth</span>,<span>displayHeight</span>);                     <span>// Set the size of the display to match the monitor width and height</span><br  />  <span>smooth</span>();                                             <span>// Draw all shapes with smooth edges.</span><br  />  f = <span>createFont</span>(<span>"Arial"</span>,24);                           <span>// Initialise the "f" font variable    - used for the "calibrating" text displayed at the beginning</span><br  />  f2 = <span>createFont</span>(<span>"Arial"</span>,96);                          <span>// Initialise the "f2" font variable   - used for the avgBPM display on screen</span><br  />  <br  />  <span>for</span>(<span>int</span> i=0; i<numOfRecs; i++){                       <span>// Initialise the array of rectangles</span><br  />    myRecs[i] = <span>new</span> Rectangle(i, numOfRecs);<br  />  }<br  />  <br  />  <span>for</span>(<span>int</span> i=0; i<totalBeats; i++){                      <span>// Initialise the BPM array</span><br  />    BPM[i] = 0;<br  />  }<br  />  <br  />  myPort = <span>new</span> Serial(<span>this</span>, Serial.<span>list</span>()[0], 9600);    <span>// Start Serial communication with the Arduino using a baud rate of 9600</span><br  />  myPort.bufferUntil(<span>'\n'</span>);                             <span>// Trigger a SerialEvent on new line</span><br  />}<br  /><br  /><br  /><span>//==DRAW==============================================================================================</span><br  /><span>void</span> <span><b>draw</b></span>(){<br  />  <span>background</span>(0);                                        <span>// Set the background to BLACK (this clears the screen each time)</span><br  />  drawRecs();                                           <span>// Method call to draw the rectangles on the screen</span><br  />  drawBPM();                                            <span>// Method call to draw the avgBPM value to the top right of the screen</span><br  />}<br  /><br  /><br  /><span>//==drawRecs==========================================================================================</span><br  /><span>void</span> drawRecs(){                                        <span>// This custom method will draw the rectangles on the screen                                </span><br  />  myRecs[0].setSize(arduinoValue);                      <span>// Set the first rectangle to match arduinoValue; any positive value will start the animation.</span><br  />  <span>for</span>(<span>int</span> i=numOfRecs-1; i>0; i--){                     <span>// The loop counts backwards for coding efficiency - and is used to draw all of the rectangles to screen</span><br  />    myRecs[i].setMult(i);                               <span>// setMulti creates the specific curve pattern. </span><br  />    myRecs[i].setRed(avgBPM);                           <span>// The rectangles become more "Red" with higher avgBPM values</span><br  />    myRecs[i].setSize(myRecs[i-1].getH());              <span>// The current rectangle size is determined by the height of the rectangle immediately to it's left</span><br  />    <span>fill</span>(myRecs[i].getR(),myRecs[i].getG(), myRecs[i].getB());                     <span>// Set the colour of this rectangle</span><br  />    <span>rect</span>(myRecs[i].getX(), myRecs[i].getY(), myRecs[i].getW(), myRecs[i].getH());  <span>// Draw this rectangle</span><br  />  }<br  />}<br  /><br  /><br  /><span>//==drawBPM===========================================================================================</span><br  /><span>void</span> drawBPM(){                                         <span>// This custom method is used to calculate the avgBPM and draw it to screen.</span><br  />  sumBPM = 0;                                           <span>// Reset the sumBPM variable</span><br  />  avgBPM = 0;                                           <span>// Reset the avgBPM variable</span><br  />  <span>boolean</span> calibrating = <span>false</span>;                          <span>// calibrating: this boolean variable is used to control when the avgBPM is displayed to screen</span><br  />  <br  />  <span>for</span>(<span>int</span> i=1; i<totalBeats; i++){<br  />    sumBPM = sumBPM + BPM[i-1];                         <span>// Sum all of the BPM values in the BPM array.</span><br  />    <span>if</span>(BPM[i-1]<1){                                     <span>// If any BPM values are equal to 0, then set the calibrating variable to true. </span><br  />      calibrating = <span>true</span>;                               <span>// This will be used later to display "calibrating" on the screen.</span><br  />    }<br  />  }<br  />  avgBPM = sumBPM/(totalBeats-1);                       <span>// Calculate the average BPM from all BPM values</span><br  />                                                        <br  />  <span>fill</span>(255);                                            <span>// The text will be displayed as WHITE text</span><br  />  <span>if</span>(calibrating){<br  />    <span>textFont</span>(f);<br  />    <span>text</span>(<span>"Calibrating"</span>, (4*<span>width</span>)/5, (<span>height</span>/5));      <span>// If the calibrating variable is TRUE, then display the word "Calibrating" on screen</span><br  />    <span>fill</span>(0);                                           <span>// Change the fill and stroke to black (0) so that other text is "hidden" while calibrating variable is TRUE</span><br  />    <span>stroke</span>(0);<br  />  } <span>else</span> {<br  />    <span>textFont</span>(f2);<br  />    <span>text</span>(avgBPM, (4*<span>width</span>)/5, (<span>height</span>/5));             <span>// If the calibrating variable is FALSE, then display the avgBPM variable on screen</span><br  />    <span>stroke</span>(255);                                       <span>// Change the stroke to white (255) to show the white line underlying the word BPM.</span><br  />  }<br  />  <br  />   <span>textFont</span>(f);<br  />   <span>text</span>(<span>"BPM"</span>, (82*<span>width</span>)/100, (<span>height</span>/11));           <span>// This will display the underlined word "BPM" when calibrating variable is FALSE.</span><br  />   <span>line</span>((80*<span>width</span>)/100, (<span>height</span>/10),(88*<span>width</span>)/100, (<span>height</span>/10));<br  />   <span>stroke</span>(0);<br  />}<br  /><br  /><br  /><span>//==serialEvent===========================================================================================</span><br  /><span>void</span> serialEvent(Serial cPort){                        <span>// This will be triggered every time a "new line" of data is received from the Arduino</span><br  /> comPortString = cPort.readStringUntil(<span>'\n'</span>);          <span>// Read this data into the comPortString variable.</span><br  /> <span>if</span>(comPortString != <span>null</span>) {                           <span>// If the comPortString variable is not NULL then</span><br  />   comPortString=<span>trim</span>(comPortString);                  <span>// trim any white space around the text.</span><br  />   <span>int</span> i = <span>int</span>(<span>map</span>(<span>Integer</span>.<span>parseInt</span>(comPortString),1,1023,1,<span>height</span>));  <span>// convert the string to an integer, and map the value so that the rectangle will fit within the screen.</span><br  />   arduinoValue = <span>float</span>(i);                            <span>// Convert the integer into a float value.</span><br  />   <span>if</span> (!beat){<br  />     <span>if</span>(arduinoValue>0){                               <span>// When a beat is detected, the "trigger" method is called.</span><br  />       trigger(<span>millis</span>());                              <span>// millis() creates a timeStamp of when the beat occured.</span><br  />       beat=<span>true</span>;                                      <span>// The beat variable is changed to TRUE to register that a beat has been detected.</span><br  />     }<br  />   }<br  />   <span>if</span> (arduinoValue<1){                                <span>// When the Arduino value returns back to zero, we will need to change the beat status to FALSE.</span><br  />     beat = <span>false</span>;<br  />   }<br  /> }<br  />} <br  /><br  /><br  /><span>//==trigger===========================================================================================</span><br  /><span>void</span> trigger(<span>int</span> time){                                <span>// This method is used to calculate the Beats per Minute (BPM) and to store the last 10 BPMs into the BPM[] array.</span><br  />  totalTime = time - lastTime;                         <span>// totalTime = the current beat time minus the last time there was a beat.</span><br  />  lastTime = time;                                     <span>// Set the lastTime variable to the current "time" for the next round of calculations.</span><br  />  BPM[beatCounter] = 60000/totalTime;                  <span>// Calculate BPM from the totalTime. 60000 = 1 minute.</span><br  />  beatCounter++;                                       <span>// Increment the beatCounter </span><br  />  <span>if</span> (beatCounter>totalBeats-1){                       <span>// Reset the beatCounter when the total number of BPMs have been stored into the BPM[] array.</span><br  />    beatCounter=0;                                     <span>// This allows us to keep the last 10 BPM calculations at all times.</span><br  />  }<br  />}<br  /><br  /><br  /><span>//==sketchFullScreen==========================================================================================</span><br  /><span>boolean</span> sketchFullScreen() {                           <span>// This puts Processing into Full Screen Mode</span><br  /> <span>return</span> <span>true</span>;<br  />}<br  /><br  /><br  /><span>//==Rectangle CLASS==================================================================================*********</span><br  /><span>class</span> Rectangle{<br  />  <span>float</span> xPos, defaultY, yPos, myWidth, myHeight, myMultiplier;    <span>// Variables used for drawing rectangles</span><br  />  <span>int</span> blueVal, greenVal, redVal;                                  <span>// Variables used for the rectangle colour</span><br  />  <br  />  Rectangle(<span>int</span> recNum, <span>int</span> nRecs){                               <span>// The rectangles are constructed using two variables. The total number of rectangles to be displayed, and the identification of this rectangle (recNum)</span><br  />    myWidth = <span>displayWidth</span>/nRecs;                                 <span>// The width of the rectangle is determined by the screen width and the total number of rectangles.</span><br  />    xPos = recNum * myWidth;                                      <span>// The x Position of this rectangle is determined by the width of the rectangles (all same) and the rectangle identifier.</span><br  />    defaultY=<span>displayHeight</span>/2;                                     <span>// The default Y position of the rectangle is half way down the screen.</span><br  />    yPos = defaultY;                                              <span>// yPos is used to adjust the position of the rectangle as the size changes.</span><br  />    myHeight = 1;                                                 <span>// The height of the rectangle starts at 1 pixel</span><br  />    myMultiplier = 1;                                             <span>// The myMultiplier variable will be used to create the funnel shaped path for the rectangles.</span><br  />    redVal = 0;                                                   <span>// The red Value starts off being 0 - but changes with avgBPM. Higher avgBPM means higher redVal</span><br  />    <br  />    <span>if</span> (recNum>0){                                                <span>// The blue Value progressively increases with every rectangle (moving to the right of the screen)</span><br  />      blueVal = (recNum*255)/nRecs;<br  />    } <span>else</span> {<br  />      blueVal = 0;<br  />    }<br  />    greenVal = 255-blueVal;                                       <span>// Initially, the green value is at the opposite end of the spectrum to the blue value.</span><br  />  }<br  />  <br  />  <span>void</span> setSize(<span>float</span> newSize){                                    <span>// This is used to set the new size of each rectangle </span><br  />    myHeight=newSize*myMultiplier;<br  />    yPos=defaultY-(newSize/2);<br  />  }<br  />  <br  />  <span>void</span> setMult(<span>int</span> i){                                            <span>// The multiplier is a function of COS, which means that it varies from 1 to 0.</span><br  />    myMultiplier = <span>cos</span>(<span>radians</span>(i));                               <span>// You can try other functions to experience different effects.</span><br  />  }<br  />  <br  />  <span>void</span> setRed(<span>int</span> r){<br  />    redVal = <span>int</span>(<span>constrain</span>(<span>map</span>(<span>float</span>(r), 60, 100, 0, 255),0,255)); <span>// setRed is used to change the redValue based on the "normal" value for resting BPM (60-100). </span><br  />    greenVal = 255 - redVal;                                       <span>// When the avgBPM > 100, redVal will equal 255, and the greenVal will equal 0.</span><br  />  }                                                                <span>// When the avgBPM < 60, redVal will equal 0, and greenVal will equal 255.</span><br  />  <br  />  <span>float</span>  getX(){                                                   <span>// get the x Position of the rectangle</span><br  />    <span>return</span> xPos;<br  />  }<br  /> <br  />  <span>float</span> getY(){                                                    <span>// get the y Position of the rectangle</span><br  />    <span>return</span> yPos;<br  />  }<br  />  <br  />  <span>float</span> getW(){                                                    <span>// get the width of the rectangle</span><br  />    <span>return</span> myWidth;<br  />  }<br  />  <br  />  <span>float</span> getH(){                                                    <span>// get the height of the rectangle</span><br  />    <span>return</span> myHeight;<br  />  }<br  />  <br  />  <span>float</span> getM(){                                                    <span>// get the Multiplier of the rectangle</span><br  />    <span>return</span> myMultiplier;<br  />  }<br  />  <br  />  <span>int</span> getB(){                                                      <span>// get the "blue" component of the rectangle colour</span><br  />    <span>return</span> blueVal;<br  />  }<br  />  <br  />  <span>int</span> getR(){                                                      <span>// get the "red" component of the rectangle colour</span><br  />    <span>return</span> redVal;<br  />  }<br  />  <br  />  <span>int</span> getG(){                                                      <span>// get the "green" component of the rectangle colour</span><br  />    <span>return</span> greenVal;<br  />  }<br  />}<br  /><br  /></pre> </td> </tr> </table></div></p> <br  />   <br  /> <p> <h4>Processing Code Discussion:</h4><br  /> </p><p>       The Rectangle class was created to store relevant information about each rectangle.        By using a custom class, we were able to design our rectangles any way we wanted.        These rectangles have properties and methods which allow us to easily control their        position, size and colour. By adding some smart functionality to each rectangle, we were able to get the rectangle to automatically        position and colour itself based on key values. </p> <p>        The Serial library is used to allow communication with the Arduino. In this Processing sketch, the values obtained from the Arduino         were converted to floats to allow easy calulations of the beats per minute (BPM).         I am aware that I have over-engineered the serialEvent method somewhat, because the Arduino         is only really sending two values. I didn't really need to convert the String. But I am happy with         the end result, and it does the job I needed it to...        </p> <div> <p> <div> <a href="http://4.bp.blogspot.com/-EVTCQ3vkgGc/VTnOarlOWSI/AAAAAAAABdc/MslEU5oirAY/s1600/Complete%2BWorkstation2.jpg"><img src="http://4.bp.blogspot.com/-EVTCQ3vkgGc/VTnOarlOWSI/AAAAAAAABdc/MslEU5oirAY/s1600/Complete%2BWorkstation2.jpg"  /> </a> </div> </p> </div> </div><!--separator --><img src="https://images-blogger-opensocial.googleusercontent.com/gadgets/proxy?url=http%3A%2F%2F1.bp.blogspot.com%2F-XQiwNpdqOxk%2FT_rKCzDh4nI%2FAAAAAAAAAQY%2FOfYBljhU6Lk%2Fs1600%2FSeparator.jpg&container=blogger&gadget=a&rewriteMime=image%2F*"  /><br  /><p> <div>     This project is quite simple. I designed it so that you could omit the Processing code if you wanted to.      In that scenario, you would only be left with a blinking LED that blinks in time with your pulse.      The Processing code takes this project to the next level. It provides a nice animation and calculates         the beats per minute (BPM). <br  />           <br  />        I hope you liked this tutorial. Please feel free to share it, comment or give it a plus one.         If you didn't like it, I would still appreciate your constructive feedback.  </div> <br  />   <div> <p> <!--separator --> <img src="https://images-blogger-opensocial.googleusercontent.com/gadgets/proxy?url=http%3A%2F%2F1.bp.blogspot.com%2F-XQiwNpdqOxk%2FT_rKCzDh4nI%2FAAAAAAAAAQY%2FOfYBljhU6Lk%2Fs1600%2FSeparator.jpg&container=blogger&gadget=a&rewriteMime=image%2F*"  /><br  /> <br  /> </p> </div> </p><p> <div>   If you like this page, please do me a favour and show your appreciation : <br  /> <br  />     <br  />   Visit my <a href="https://plus.google.com/u/0/b/107402020974762902161/107402020974762902161/posts">ArduinoBasics Google + page</a>.<br  />   Follow me on Twitter by looking for <a href="https://twitter.com/ArduinoBasics">ScottC @ArduinoBasics</a>.<br  />   I can also be found on <a href="https://www.pinterest.com/ArduinoBasics/">Pinterest</a> and <a href="https://instagram.com/arduinobasics">Instagram</a>. <br  />   Have a look at my videos on my <a href="https://www.youtube.com/user/ScottCMe/videos">YouTube channel</a>.<br  /> </div> </p> <br  />   <br  />   <p> <div> <a href="http://3.bp.blogspot.com/-x_TA-qhOCzM/VTnULXoWhQI/AAAAAAAABds/quh02BWGsec/s1600/Slide1.JPG"><img src="http://3.bp.blogspot.com/-x_TA-qhOCzM/VTnULXoWhQI/AAAAAAAABds/quh02BWGsec/s1600/Slide1.JPG"  /></a></div><br  /> </p> <br  />   <br  />   <br  />   <div> <p> <!--separator --> <img src="https://images-blogger-opensocial.googleusercontent.com/gadgets/proxy?url=http%3A%2F%2F1.bp.blogspot.com%2F-XQiwNpdqOxk%2FT_rKCzDh4nI%2FAAAAAAAAAQY%2FOfYBljhU6Lk%2Fs1600%2FSeparator.jpg&container=blogger&gadget=a&rewriteMime=image%2F*"  /><br  /> <br  /> </p> </div> <p>  However, if you do not have a google profile... <br  />Feel free to share this page with your friends in any way you see fit.  </p>

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/* =================================================================================================
      Project: Arduino Beatbox
       Author: Scott C
      Created: 9th April 2015
  Arduino IDE: 1.6.2
      Website: http://arduinobasics.blogspot.com/p/arduino-basics-projects-page.html
  Description: This project uses home made capacitive sensors to trigger over 130 MP3 sounds
               on the Grove Serial MP3 player. 
               
               The ADCTouch library is used to eliminate the resistors from the Capacitive sensing circuit. 
               The code used for capacitive sensing was adapted from the ADCTouch library example sketches. 
               You can find the ADCTouch library and relevant example code here:
               http://playground.arduino.cc/Code/ADCTouch
               
               "Advanced Arduino ADC" is used to improve the analogRead() speed, and enhance the
               drum pad or capacitive sensor response time. The Advanced Arduino ADC code 
               was adapted from this site:
               http://www.microsmart.co.za/technical/2014/03/01/advanced-arduino-adc/
               
               
=================================================================================================== */
  #include <ADCTouch.h>
  #include <SoftwareSerial.h>
  
  
  //Global variables
  //===================================================================================================
  int potPin = A4;                           //Grove Sliding potentiometer is connected to Analog Pin 4
  int potVal = 0;
  byte mp3Vol = 0;                           //Variable used to control the volume of the MP3 player
  byte oldVol = 0;
  
  int buttonPin = 5;                         //Grove Button is connected to Digital Pin 5
  int buttonStatus = 0;
  
  byte SongNum[4] = {0x01,0x02,0x03,0x04};  //The first 4 songs will be assigned to the drum pads upon initialisation
  byte numOfSongs = 130;                    //Total number of MP3 songs/sounds loaded onto the SDHC card
  
  long randNumber;                          //Variable used to hold the random number - used to randomise the sounds.
  
  int ledState[4];                          //Used to keep track of the status of all LEDs (on or off)
  int counter = 0;
  
  SoftwareSerial mp3(3, 4);                 // The Grove MP3 Player is connected to Arduino digital Pin 3 and 4 (Serial communication)
       
  int ref0, ref1, ref2, ref3;               //reference values to remove offset
  int threshold = 100;
      
  // Define the ADC prescalers
  const unsigned char PS_64 = (1 << ADPS2) | (1 << ADPS1);
  const unsigned char PS_128 = (1 << ADPS2) | (1 << ADPS1) | (1 << ADPS0);
  
  
  
  //Setup()
  //===================================================================================================
  void setup(){
    //Initialise the Grove MP3 Module
    delay(2500);                              //Allow the MP3 module to power up        
    mp3.begin(9600);                          //Begin Serial communication with the MP3 module
    setPlayMode(0x00);                        //0x00 = Single song - played once ie. not repeated.  (default)
    
    //Define the Grove Button as an INPUT
    pinMode(buttonPin, INPUT);
    
    //Define the 4 LED Pins as OUTPUTs
    pinMode(8, OUTPUT);                       //Green LED
    pinMode(9, OUTPUT);                       //Blue LED
    pinMode(10, OUTPUT);                      //Red LED
    pinMode(11, OUTPUT);                      //Yellow LED
    
    //Make sure each LED is OFF, and store the state of the LED into a variable.
    for(int i=8;i<12;i++){
      digitalWrite(i, LOW);
      ledState[i-8]=0;
    } 
    
    //Double our clock speed from 125 kHz to 250 kHz
    ADCSRA &= ~PS_128;   // set up the ADC
    ADCSRA |= PS_64;    // set our own prescaler to 64 
    
    //Create reference values to account for the capacitance of each pad.
    ref0 = ADCTouch.read(A0, 500);
    ref1 = ADCTouch.read(A1, 500);      //Take 500 readings
    ref2 = ADCTouch.read(A2, 500);
    ref3 = ADCTouch.read(A3, 500);
    
     //This helps to randomise the drum pads.
     randomSeed(analogRead(0));
  }
  
  
  
  // Loop()
  //===================================================================================================     
  void loop(){
     
    //Take a reading from the Grove Sliding Potentiometer, and set volume accordingly
    potVal = analogRead(potPin);
    mp3Vol = map(potVal, 0, 1023, 0,31);              // Convert the potentometer reading (0 - 1023) to fit within the MP3 player's Volume range (0 - 31)
    if((mp3Vol>(oldVol+1))|(mp3Vol<(oldVol-1))){      // Only make a change to the Volume on the Grove MP3 player when the potentiometer value changes
      oldVol = mp3Vol;
      setVolume(mp3Vol);
      delay(10);                                      // This delay is necessary with Serial communication to MP3 player
    }
    
    //Take a reading from the Pin attached to the Grove Button. If pressed, randomise the MP3 songs/sounds for each drum pad, and make the LEDs blink randomly.
    buttonStatus = digitalRead(buttonPin);
    if(buttonStatus==HIGH){
      SongNum[0]=randomSongChooser(1, 30);
      SongNum[1]=randomSongChooser(31, 60);
      SongNum[2]=randomSongChooser(61, 86);
      SongNum[3]=randomSongChooser(87, (int)numOfSongs);
      randomLEDBlink();
    }
    
    //Get the capacitive readings from each drum pad: 50 readings are taken from each pad. (default is 100) 
    int value0 = ADCTouch.read(A0,50);        //  Green drum pad
    int value1 = ADCTouch.read(A1,50);        //   Blue drum pad
    int value2 = ADCTouch.read(A2,50);        //    Red drum pad
    int value3 = ADCTouch.read(A3,50);        // Yellow drum pad
    
    //Remove the offset to account for the baseline capacitance of each pad.
    value0 -= ref0;       
    value1 -= ref1;
    value2 -= ref2;
    value3 -= ref3;
    
    
    //If any of the values exceed the designated threshold, then play the song/sound associated with that drum pad.
    //The associated LED will stay on for the whole time the drum pad is pressed, providing the value remains above the threshold. 
    //The LED will turn off when the pad is not being touched or pressed.
    if(value0>threshold){
      digitalWrite(8, HIGH);
      playSong(00,SongNum[0]);
    }else{
      digitalWrite(8,LOW);
    }
    
    if(value1>threshold){
      digitalWrite(9, HIGH);
      playSong(00,SongNum[1]);
    }else{
      digitalWrite(9,LOW);
    }
    
    if(value2>threshold){
      digitalWrite(10, HIGH);
      playSong(00,SongNum[2]);
    }else{
      digitalWrite(10,LOW);
    }
    
    if(value3>threshold){
      digitalWrite(11, HIGH);
      playSong(00,SongNum[3]);
    }else{
      digitalWrite(11,LOW);
    }
  }
      
   
  // writeToMP3: 
  // a generic function that simplifies each of the methods used to control the Grove MP3 Player
  //===================================================================================================
  void writeToMP3(byte MsgLEN, byte A, byte B, byte C, byte D, byte E, byte F){
    byte codeMsg[] = {MsgLEN, A,B,C,D,E,F};
    mp3.write(0x7E);                        //Start Code for every command = 0x7E
    for(byte i = 0; i<MsgLEN+1; i++){
      mp3.write(codeMsg[i]);                //Send the rest of the command to the GROVE MP3 player
    }
  }
  
  
  //setPlayMode: defines how each song is to be played
  //===================================================================================================
  void setPlayMode(byte playMode){
    /* playMode options:
          0x00 = Single song - played only once ie. not repeated.  (default)
          0x01 = Single song - cycled ie. repeats over and over.
          0x02 = All songs - cycled 
          0x03 = play songs randomly                                           */
    writeToMP3(0x03, 0xA9, playMode, 0x7E, 0x00, 0x00, 0x00);  
  }
  
  
  //playSong: tells the Grove MP3 player to play the song/sound, and also which song/sound to play
  //===================================================================================================
  void playSong(byte songHbyte, byte songLbyte){
    writeToMP3(0x04, 0xA0, songHbyte, songLbyte, 0x7E, 0x00, 0x00);            
    delay(100);
  }
  
  
  //setVolume: changes the Grove MP3 player's volume to the designated level (0 to 31)
  //===================================================================================================
  void setVolume(byte Volume){
    byte tempVol = constrain(Volume, 0, 31);             //Volume range = 00 (muted) to 31 (max volume)
    writeToMP3(0x03, 0xA7, tempVol, 0x7E, 0x00, 0x00, 0x00); 
  }
  
  
  //randomSongChooser: chooses a random song to play. The range of songs to choose from
  //is limited and defined by the startSong and endSong parameters.
  //===================================================================================================
  byte randomSongChooser(int startSong, int endSong){
    randNumber = random(startSong, endSong);
    return((byte) randNumber);
  }
  
  
  //randomLEDBlink: makes each LED blink randomly. The LEDs are attached to digital pins 8 to 12.
  //===================================================================================================
  void randomLEDBlink(){
   counter=8;
   for(int i=0; i<40; i++){
     int x = constrain((int)random(8,12),8,12);
     toggleLED(x);
     delay(random(50,100-i));
   }
     
    for(int i=8;i<12;i++){
      digitalWrite(i, HIGH);
    }
    delay(1000);
    for(int i=8;i<12;i++){
      digitalWrite(i, LOW);
      ledState[i-8]=0;
    }
  }
  
  
  //toggleLED: is used by the randomLEDBlink method to turn each LED on and off (randomly).
  //===================================================================================================
  void toggleLED(int pinNum){
    ledState[pinNum-8]= !ledState[pinNum-8];
    digitalWrite(pinNum, ledState[pinNum-8]);
  }
    

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/* =================================================================================================
      Project: Arduino Beatbox
       Author: Scott C
      Created: 9th April 2015
  Arduino IDE: 1.6.2
      Website: http://arduinobasics.blogspot.com/p/arduino-basics-projects-page.html
  Description: This project uses home made capacitive sensors to trigger over 130 MP3 sounds
               on the Grove Serial MP3 player. 
               
               The ADCTouch library is used to eliminate the resistors from the Capacitive sensing circuit. 
               The code used for capacitive sensing was adapted from the ADCTouch library example sketches. 
               You can find the ADCTouch library and relevant example code here:
               http://playground.arduino.cc/Code/ADCTouch
               
               "Advanced Arduino ADC" is used to improve the analogRead() speed, and enhance the
               drum pad or capacitive sensor response time. The Advanced Arduino ADC code 
               was adapted from this site:
               http://www.microsmart.co.za/technical/2014/03/01/advanced-arduino-adc/
               
               
=================================================================================================== */
  #include <ADCTouch.h>
  #include <SoftwareSerial.h>
  
  
  //Global variables
  //===================================================================================================
  int potPin = A4;                           //Grove Sliding potentiometer is connected to Analog Pin 4
  int potVal = 0;
  byte mp3Vol = 0;                           //Variable used to control the volume of the MP3 player
  byte oldVol = 0;
  
  int buttonPin = 5;                         //Grove Button is connected to Digital Pin 5
  int buttonStatus = 0;
  
  byte SongNum[4] = {0x01,0x02,0x03,0x04};  //The first 4 songs will be assigned to the drum pads upon initialisation
  byte numOfSongs = 130;                    //Total number of MP3 songs/sounds loaded onto the SDHC card
  
  long randNumber;                          //Variable used to hold the random number - used to randomise the sounds.
  
  int ledState[4];                          //Used to keep track of the status of all LEDs (on or off)
  int counter = 0;
  
  SoftwareSerial mp3(3, 4);                 // The Grove MP3 Player is connected to Arduino digital Pin 3 and 4 (Serial communication)
       
  int ref0, ref1, ref2, ref3;               //reference values to remove offset
  int threshold = 100;
      
  // Define the ADC prescalers
  const unsigned char PS_64 = (1 << ADPS2) | (1 << ADPS1);
  const unsigned char PS_128 = (1 << ADPS2) | (1 << ADPS1) | (1 << ADPS0);
  
  
  
  //Setup()
  //===================================================================================================
  void setup(){
    //Initialise the Grove MP3 Module
    delay(2500);                              //Allow the MP3 module to power up        
    mp3.begin(9600);                          //Begin Serial communication with the MP3 module
    setPlayMode(0x00);                        //0x00 = Single song - played once ie. not repeated.  (default)
    
    //Define the Grove Button as an INPUT
    pinMode(buttonPin, INPUT);
    
    //Define the 4 LED Pins as OUTPUTs
    pinMode(8, OUTPUT);                       //Green LED
    pinMode(9, OUTPUT);                       //Blue LED
    pinMode(10, OUTPUT);                      //Red LED
    pinMode(11, OUTPUT);                      //Yellow LED
    
    //Make sure each LED is OFF, and store the state of the LED into a variable.
    for(int i=8;i<12;i++){
      digitalWrite(i, LOW);
      ledState[i-8]=0;
    } 
    
    //Double our clock speed from 125 kHz to 250 kHz
    ADCSRA &= ~PS_128;   // set up the ADC
    ADCSRA |= PS_64;    // set our own prescaler to 64 
    
    //Create reference values to account for the capacitance of each pad.
    ref0 = ADCTouch.read(A0, 500);
    ref1 = ADCTouch.read(A1, 500);      //Take 500 readings
    ref2 = ADCTouch.read(A2, 500);
    ref3 = ADCTouch.read(A3, 500);
    
     //This helps to randomise the drum pads.
     randomSeed(analogRead(0));
  }
  
  
  
  // Loop()
  //===================================================================================================     
  void loop(){
     
    //Take a reading from the Grove Sliding Potentiometer, and set volume accordingly
    potVal = analogRead(potPin);
    mp3Vol = map(potVal, 0, 1023, 0,31);              // Convert the potentometer reading (0 - 1023) to fit within the MP3 player's Volume range (0 - 31)
    if((mp3Vol>(oldVol+1))|(mp3Vol<(oldVol-1))){      // Only make a change to the Volume on the Grove MP3 player when the potentiometer value changes
      oldVol = mp3Vol;
      setVolume(mp3Vol);
      delay(10);                                      // This delay is necessary with Serial communication to MP3 player
    }
    
    //Take a reading from the Pin attached to the Grove Button. If pressed, randomise the MP3 songs/sounds for each drum pad, and make the LEDs blink randomly.
    buttonStatus = digitalRead(buttonPin);
    if(buttonStatus==HIGH){
      SongNum[0]=randomSongChooser(1, 30);
      SongNum[1]=randomSongChooser(31, 60);
      SongNum[2]=randomSongChooser(61, 86);
      SongNum[3]=randomSongChooser(87, (int)numOfSongs);
      randomLEDBlink();
    }
    
    //Get the capacitive readings from each drum pad: 50 readings are taken from each pad. (default is 100) 
    int value0 = ADCTouch.read(A0,50);        //  Green drum pad
    int value1 = ADCTouch.read(A1,50);        //   Blue drum pad
    int value2 = ADCTouch.read(A2,50);        //    Red drum pad
    int value3 = ADCTouch.read(A3,50);        // Yellow drum pad
    
    //Remove the offset to account for the baseline capacitance of each pad.
    value0 -= ref0;       
    value1 -= ref1;
    value2 -= ref2;
    value3 -= ref3;
    
    
    //If any of the values exceed the designated threshold, then play the song/sound associated with that drum pad.
    //The associated LED will stay on for the whole time the drum pad is pressed, providing the value remains above the threshold. 
    //The LED will turn off when the pad is not being touched or pressed.
    if(value0>threshold){
      digitalWrite(8, HIGH);
      playSong(00,SongNum[0]);
    }else{
      digitalWrite(8,LOW);
    }
    
    if(value1>threshold){
      digitalWrite(9, HIGH);
      playSong(00,SongNum[1]);
    }else{
      digitalWrite(9,LOW);
    }
    
    if(value2>threshold){
      digitalWrite(10, HIGH);
      playSong(00,SongNum[2]);
    }else{
      digitalWrite(10,LOW);
    }
    
    if(value3>threshold){
      digitalWrite(11, HIGH);
      playSong(00,SongNum[3]);
    }else{
      digitalWrite(11,LOW);
    }
  }
      
   
  // writeToMP3: 
  // a generic function that simplifies each of the methods used to control the Grove MP3 Player
  //===================================================================================================
  void writeToMP3(byte MsgLEN, byte A, byte B, byte C, byte D, byte E, byte F){
    byte codeMsg[] = {MsgLEN, A,B,C,D,E,F};
    mp3.write(0x7E);                        //Start Code for every command = 0x7E
    for(byte i = 0; i<MsgLEN+1; i++){
      mp3.write(codeMsg[i]);                //Send the rest of the command to the GROVE MP3 player
    }
  }
  
  
  //setPlayMode: defines how each song is to be played
  //===================================================================================================
  void setPlayMode(byte playMode){
    /* playMode options:
          0x00 = Single song - played only once ie. not repeated.  (default)
          0x01 = Single song - cycled ie. repeats over and over.
          0x02 = All songs - cycled 
          0x03 = play songs randomly                                           */
    writeToMP3(0x03, 0xA9, playMode, 0x7E, 0x00, 0x00, 0x00);  
  }
  
  
  //playSong: tells the Grove MP3 player to play the song/sound, and also which song/sound to play
  //===================================================================================================
  void playSong(byte songHbyte, byte songLbyte){
    writeToMP3(0x04, 0xA0, songHbyte, songLbyte, 0x7E, 0x00, 0x00);            
    delay(100);
  }
  
  
  //setVolume: changes the Grove MP3 player's volume to the designated level (0 to 31)
  //===================================================================================================
  void setVolume(byte Volume){
    byte tempVol = constrain(Volume, 0, 31);             //Volume range = 00 (muted) to 31 (max volume)
    writeToMP3(0x03, 0xA7, tempVol, 0x7E, 0x00, 0x00, 0x00); 
  }
  
  
  //randomSongChooser: chooses a random song to play. The range of songs to choose from
  //is limited and defined by the startSong and endSong parameters.
  //===================================================================================================
  byte randomSongChooser(int startSong, int endSong){
    randNumber = random(startSong, endSong);
    return((byte) randNumber);
  }
  
  
  //randomLEDBlink: makes each LED blink randomly. The LEDs are attached to digital pins 8 to 12.
  //===================================================================================================
  void randomLEDBlink(){
   counter=8;
   for(int i=0; i<40; i++){
     int x = constrain((int)random(8,12),8,12);
     toggleLED(x);
     delay(random(50,100-i));
   }
     
    for(int i=8;i<12;i++){
      digitalWrite(i, HIGH);
    }
    delay(1000);
    for(int i=8;i<12;i++){
      digitalWrite(i, LOW);
      ledState[i-8]=0;
    }
  }
  
  
  //toggleLED: is used by the randomLEDBlink method to turn each LED on and off (randomly).
  //===================================================================================================
  void toggleLED(int pinNum){
    ledState[pinNum-8]= !ledState[pinNum-8];
    digitalWrite(pinNum, ledState[pinNum-8]);
  }