Posts with «slide potentiometer» label

Arduino BeatBox

Create your very own Arduino BeatBox !

Home-made capacitive touch sensors are used to trigger the MP3 drum sounds stored on the Grove Serial MP3 player. I have used a number of tricks to get the most out of this module, and I was quite impressed on how well it did. Over 130 sounds were loaded onto the SDHC card. Most were drum sounds, but I added some farm animal noises to provide an extra element of surprise and entertainment. You can put any sounds you want on the module and play them back quickly. We'll put the Grove Serial MP3 module through it's paces and make it into a neat little BeatBox !!


Key learning objectives

  • How to make your own beatbox
  • How to make capacitive drum pad sensors without using resistors
  • How to speed up Arduino's Analog readings for better performance
  • How to generate random numbers on your Arduino


Parts Required:

Making the drum pads


 
 

Fritzing Sketch


 


 
 

Grove Connections


 


 
 

Grove Connections (without base shield)


 


 
 

Arduino Sketch


 
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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]);
  }


 

Arduino Code Discussion

You can see from the Arduino code above, that it uses the ADCTouch library. This library was chosen over the Capacitive Sensing Library to eliminate the need for a high value resistor which are commonly found in Capacitive Sensing projects).
 
To increase the speed of the Analog readings, I utilised one of the "Advanced Arduino ADC" techniques described by Guy van den Berg on this Microsmart website.
 
The readings are increased by modifying the Arduino's ADC clock speed from 125kHz to 250 kHz. I did notice an overall better response time with this modification. However, the Grove Serial MP3 player is limited by it's inability to play more than one song or sound at a time. This means that if you hit another drum pad while the current sound is playing, it will stop playing the current sound, and then play the selected sound. The speed at which it can perform this task was quite impressive. In fact it was much better than I thought it would be. But if you are looking for polyphonic playability, you will be dissapointed.
 
This Serial MP3 module makes use of a high quality MP3 audio chip known as the "WT5001". Therefore, you should be able to get some additional features and functionality from this document. Plus you may find some extra useful info from the Seeedstudio wiki. I have re-used some code from the Arduino Boombox tutorial... you will find extra Grove Serial MP3 functions on that page.
 
I will warn you... the Grove Serial MP3 player can play WAV files, however for some reason it would not play many of the sound files in this format. Once the sounds were converted to the MP3 format, I did not look back. So if you decide to take on this project, make sure your sound files are in MP3 format, you'll have a much better outcome.
 
I decided to introduce a random sound selection for each drum pad to extend the novelty of this instrument, which meant that I had to come up with a fancy way to illuminate the LEDs. I demonstrated some of my other LED sequences on my instagram account. I sometimes use instagram to show my work in progress.
 
Have a look at the video below to see this project in action, and putting the Grove Serial MP3 player through it's paces.
 

The Video


 


First there was the Arduino Boombox, and now we have the Arduino Beatbox..... who knows what will come next !
 
Whenever I create a new project, I like to improve my Arduino knowledge. Sometimes it takes me into some rather complicated topics. There is a lot I do not know about Arduino, but I am enjoying the journey. I hope you are too !! Please Google plus one this post if it helped you in any way. These tutorials are free, which means I survive on feedback and plus ones... all you have to do is just scroll a little bit more and click that button :)

 
 



If you like this page, please do me a favour and show your appreciation :

 
Visit my ArduinoBasics Google + page.
Follow me on Twitter by looking for ScottC @ArduinoBasics.
I can also be found on Pinterest and Instagram.
Have a look at my videos on my YouTube channel.


 
 

 
 
 



However, if you do not have a google profile...
Feel free to share this page with your friends in any way you see fit.

Arduino BeatBox

Create your very own Arduino BeatBox !

Home-made capacitive touch sensors are used to trigger the MP3 drum sounds stored on the Grove Serial MP3 player. I have used a number of tricks to get the most out of this module, and I was quite impressed on how well it did. Over 130 sounds were loaded onto the SDHC card. Most were drum sounds, but I added some farm animal noises to provide an extra element of surprise and entertainment. You can put any sounds you want on the module and play them back quickly. We'll put the Grove Serial MP3 module through it's paces and make it into a neat little BeatBox !!


Key learning objectives

  • How to make your own beatbox
  • How to make capacitive drum pad sensors without using resistors
  • How to speed up Arduino's Analog readings for better performance
  • How to generate random numbers on your Arduino


Parts Required:

Making the drum pads


 
 

Fritzing Sketch


 


 
 

Grove Connections


 


 
 

Grove Connections (without base shield)


 


 
 

Arduino Sketch


 
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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]);
  }


 

Arduino Code Discussion

You can see from the Arduino code above, that it uses the ADCTouch library. This library was chosen over the Capacitive Sensing Library to eliminate the need for a high value resistor which are commonly found in Capacitive Sensing projects).
 
To increase the speed of the Analog readings, I utilised one of the "Advanced Arduino ADC" techniques described by Guy van den Berg on this Microsmart website.
 
The readings are increased by modifying the Arduino's ADC clock speed from 125kHz to 250 kHz. I did notice an overall better response time with this modification. However, the Grove Serial MP3 player is limited by it's inability to play more than one song or sound at a time. This means that if you hit another drum pad while the current sound is playing, it will stop playing the current sound, and then play the selected sound. The speed at which it can perform this task was quite impressive. In fact it was much better than I thought it would be. But if you are looking for polyphonic playability, you will be dissapointed.
 
This Serial MP3 module makes use of a high quality MP3 audio chip known as the "WT5001". Therefore, you should be able to get some additional features and functionality from this document. Plus you may find some extra useful info from the Seeedstudio wiki. I have re-used some code from the Arduino Boombox tutorial... you will find extra Grove Serial MP3 functions on that page.
 
I will warn you... the Grove Serial MP3 player can play WAV files, however for some reason it would not play many of the sound files in this format. Once the sounds were converted to the MP3 format, I did not look back. So if you decide to take on this project, make sure your sound files are in MP3 format, you'll have a much better outcome.
 
I decided to introduce a random sound selection for each drum pad to extend the novelty of this instrument, which meant that I had to come up with a fancy way to illuminate the LEDs. I demonstrated some of my other LED sequences on my instagram account. I sometimes use instagram to show my work in progress.
 
Have a look at the video below to see this project in action, and putting the Grove Serial MP3 player through it's paces.
 

The Video


 


First there was the Arduino Boombox, and now we have the Arduino Beatbox..... who knows what will come next !
 
Whenever I create a new project, I like to improve my Arduino knowledge. Sometimes it takes me into some rather complicated topics. There is a lot I do not know about Arduino, but I am enjoying the journey. I hope you are too !! Please Google plus one this post if it helped you in any way. These tutorials are free, which means I survive on feedback and plus ones... all you have to do is just scroll a little bit more and click that button :)

 
 



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Have a look at my videos on my YouTube channel.


 
 

 
 
 



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DIY Canon Intervalometer using Arduino



An intervalometer allows you to take photos at set intervals to view a slow process in super fast speed. Watching paint dry is just as boring in fast motion as it is at normal speed, however, when you point your camera to the clouds in the sky, you can get some amazing effects.
 
By taking a picture every 3 seconds, and then playing the sequence back at 30 frames a second, you will get to see a 10 minute event in just 7 seconds.To get a nice flowing motion picture, you need to get a good balance between the recording frame rate, and the play-back frame rate.
 


 
The recording frame rate is limited by the amount of memory you have in your camera, the length of the captured event, battery charge, and the camera's general capabilities. The playback frame rate needs to be fast enough to prevent jittering, but not so fast that you lose the event in a blink of an eye. The more you practice with different subject matters, the more you get a feel for how long you need to keep the camera running and how long to leave between shots.
 
When taking pictures of the clouds, you can generally use a 3-5 second frame rate, depending on their speed across the sky. To capture the flow of traffic, I would recommend a picture every 1-2 seconds. However, for really slow events like a plant growing, you may need to extend the frame capture rate significantly. You will get a better idea once you try it for yourself.
 
 

 
This tutorial follows on from the Arduino selfie tutorial, so you might notice some similarities. However, in this tutorial, we will have more control over the intervalometer by using a sliding potentiometer and an LED bar. The pin layout is slightly different from the Arduino Selfie tutorial - so best to start from scratch to avoid pin misconfigurations.
 

Warning : Any circuit you build for your camera (including this one) is at your own risk. I will not take responsibility for any damage caused to any of your equipment.
 
I found out that my Canon Powershot SX50 HS camera has a port on the side for a remote switch. In the "Optional Accessories" section of the camera brochure, it identifies the remote switch model as RS-60E3. I then looked up the model number on this website to find out the size of the jack (3 core, 2.5mm), and the pinout (Ground, focus and shutter) required to emulate the remote switch. Once I had this information, I was able to solder some really long wires to the jack and connect up the circuit (as described below).
 
I use Time-Lapse tool to stitch all of the pictures together to create a movie/animation.
 
You will need to download and install the LED_Bar library from Seeedstudio into your Arduino IDE libraries folder in order to use the LED Bar in this tutorial. For more information about the LED Bar - visit the LED Bar Seeed-Studio wiki.
 

Parts Required:





 

Fritzing Sketch


 

 

 

 


 
 

Connection Tables


 
Arduino to Relay Module:
 

 
 
Relay Module to Camera:
 

 
 
Arduino to Slide Potentiometer:
 

 
 
Arduino to LED Bar:
 


 
 

Arduino Sketch


 
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/* ===============================================================
      Project: DIY Canon Intervalometer using Arduino
       Author: Scott C
      Created: 9th October 2014
  Arduino IDE: 1.0.5
      Website: http://arduinobasics.blogspot.com/p/arduino-basics-projects-page.html
  Description: Use Arduino as an intervalometer for Canon PowerShot SX50 HS
               A slide potentiometer is used to control the time between photos.
               The LED Bar is used to display the delay between photos.
               A 3 core 2.5mm jack is used to connect the Arduino and Relay module to the Camera.
================================================================== */

 /* You will need to download and install the LED_Bar library from here: https://github.com/Seeed-Studio/Grove_LED_Bar */
 #include <LED_Bar.h>

 /* Connect 5V on Arduino to VCC on Relay Module
    Connect GND on Arduino to GND on Relay Module */

 #define CH1 7   // Connect Digital Pin 7 on Arduino to CH1 on Relay Module
 #define CH3 6   // Connect Digital Pin 6 on Arduino to CH3 on Relay Module
 
 int potPin=A0; //Connect Slide potentiometer to Analog Pin 0 on Grove Base Shield
 int potValue=0; //The variable used to hold the value of the potentiometer

 LED_Bar bar1(9,8); //Connect LED Bar to Digital I/O 8 on Grove base shield.
                   //The LED Bar actually uses digital pin 8 and 9.

 void setup(){
   pinMode(CH1, OUTPUT);
   pinMode(CH3, OUTPUT);
   
   //Turn OFF any power to the Relay channels
   digitalWrite(CH1,LOW);
   digitalWrite(CH3,LOW);
   delay(2000); //Wait 2 seconds before starting sequence
   
   //Focus camera by switching Relay 1
   digitalWrite(CH1, HIGH);
   delay(2000);
   digitalWrite(CH1, LOW); //Stop focus
   delay(3000);
 }

 void loop(){
      // Read the slide potentiometer and convert the reading to a value between 0 and 10.
      potValue=constrain(map(analogRead(potPin),0,1000,0,10),0,10);
      
      //Use the pot value to create a visual count-down display on the LED bar.
      for(int i = potValue; i>0; i--){
        bar1.setLevel(i);
        delay(1000);
      }
      
      //If the pot value is less than 1, then delay for 30 seconds.
      if(potValue<1){
        delay(30000);
      }
      
      //Turn LED Bar off when taking photo
      bar1.setLevelReverse(0);
      
      //Press shutter button for 0.1 seconds. Modify delay if required.
      digitalWrite(CH3, HIGH);
      delay(100);
      digitalWrite(CH3,LOW); //Release shutter button
 }



 


The Video


 



This project shows how to make your Canon Powershot SX50 HS a whole lot smarter using an Arduino. There are so many things that look so different with an intervalometer. While I connected a slide potentiometer to the Arduino to provide extra flexibility, and an LED Bar for visual feedback, there are many other sensors out there that can be combined with the camera. For example, you could use a PIR sensor to take a picture when movement is detected. Or take a picture when a laser trip-wire is broken. What about sound activation, light activation, leak detection.... the options are limitless.
 
This has been one of my favorite projects, it was a lot of fun, and very interesting.
I highly recommend that you try it out!



If you like this page, please do me a favour and show your appreciation :

 
 
Visit my ArduinoBasics Google + page.
Follow me on Twitter by looking for ScottC @ArduinoBasics.
Have a look at my videos on my YouTube channel.


 
 

 
 
 


However, if you do not have a google profile...
Feel free to share this page with your friends in any way you see fit.