Posts with «seeedstudio» label

Digital Rain Cloud

 
 

Description

This is a very simple project that turns a Rainbow Cube Kit from Seeedstudio, into a digital rain cloud. It features a relaxing rain animation which is ruined by a not-so-relaxing yet somewhat realistic lightning effect. The animation has a very random pattern, and is quite satisfying to watch. The strategically placed cotton wool on the top of the cube makes all the difference to the project, and is sure to impress all of your friends. Luckily, I have done all of the hard work for you. You will find the full source code for the animation sequence below. You just have to provide the Rainbow Cube Kit and the cotton wool. Have fun !!

 
 

Visual report from Maker Faire Shenzhen

Arduino/Genuino team were in China last month to be part of Shenzhen Maker Faire and present to local makers the new Genuino boards, together with Seeedstudio. They  also had the pleasure to meet with Arduino users, teachers, students and makers of all ages with great skills.
Here’s a selection of pictures form those amazing days (all the pictures are on our Flickr).

Thanks to all the people visiting our booth and warmly welcoming us in China!

Watch Makezine’s interview with Massimo Banzi and Eric Pan

According to Make, the biggest news coming out of Maker Faire Shenzhen, outside the size and intensity of the event itself, was the partnership involving our team at Arduino and SeeedStudio.  Massimo Banzi during his talk presented Arduino boards using the new sister brand Genuino which will be made in China by Seeedstudio.

Dale Dougherty was in Shenzhen with them and did this video interview and article:

Arduino and Seeedstudio announce partnership in Shenzhen

Today, June 20th, 2015, Massimo Banzi, Co-founder of Arduino, and Eric Pan, founder and CEO of Seeedstudio announced at Maker Faire Shenzhen 2015 a strategic partnership between Arduino LLC and Seeedstudio.

Seeedstudio will manufacture and distribute Arduino LLC products using the new Genuino brand in China and other Asian markets.

The new Genuino name certifies the authenticity of boards, in line with the open hardware and open source philosophy that has always characterized Arduino. Genuino is Arduino LLC new sister-brand created by co-founders Massimo Banzi, David Cuartielles, Tom Igoe and David Mellis for markets outside of the USA.

“We are very excited to partner with SeeedStudio to manufacture our products in China. We’ve known and appreciated Seeed for years, we share the same values and I think they are one of the most forward looking companies in China” said Massimo Banzi.

And he also explained about Genuino: “Arduino is very popular in China but the brand is used heavily without permission. Genuino allows the market to clearly identify which products are contributing to the Open Source Hardware process. With Genuino, the Arduino.cc community will easily be able to recognize the partners who are contributing to support the development of the platform.”

Eric Pan, founder of Seeedstudio, explained: “Arduino is becoming a global language of making, we are proud to help provide Genuino branded localized products to carry on the conversation in China. Here we already have a huge Arduino user base and growing, it’s time to get us involved deeper with global ecosystem. “

Genuino-branded products will be sold on Seeed’s store on Taobao and soon on http://www.genuino.cc.

The partnership between Arduino LLC and Seeedstudio is a bold new step of a global development plan by Arduino LLC. Arduino LLC has recently launched the Genuino brand and is already working with market-leading, innovative manufacturers/distributors in Asia, Europe, South America, Canada and Africa.

Arduino and Seeedstudio announce partnership in Shenzhen

Today, June 20th, 2015, Massimo Banzi, Co-founder of Arduino, and Eric Pan, founder and CEO of Seeedstudio announced at Maker Faire Shenzhen 2015 a strategic partnership between Arduino LLC and Seeedstudio.

Seeedstudio will manufacture and distribute Arduino LLC products using the new Genuino brand in China and other Asian markets.

The new Genuino name certifies the authenticity of boards, in line with the open hardware and open source philosophy that has always characterized Arduino. Genuino is Arduino LLC new sister-brand created by co-founders Massimo Banzi, David Cuartielles, Tom Igoe and David Mellis for markets outside of the USA.

“We are very excited to partner with SeeedStudio to manufacture our products in China. We’ve known and appreciated Seeed for years, we share the same values and I think they are one of the most forward looking companies in China” said Massimo Banzi.

And he also explained about Genuino: “Arduino is very popular in China but the brand is used heavily without permission. Genuino allows the market to clearly identify which products are contributing to the Open Source Hardware process. With Genuino, the Arduino.cc community will easily be able to recognize the partners who are contributing to support the development of the platform.”

Eric Pan, founder of Seeedstudio, explained: “Arduino is becoming a global language of making, we are proud to help provide Genuino branded localized products to carry on the conversation in China. Here we already have a huge Arduino user base and growing, it’s time to get us involved deeper with global ecosystem. “

Genuino-branded products will be sold on Seeed’s store on Taobao and soon on http://www.genuino.cc.

The partnership between Arduino LLC and Seeedstudio is a bold new step of a global development plan by Arduino LLC. Arduino LLC has recently launched the Genuino brand and is already working with market-leading, innovative manufacturers/distributors in Asia, Europe, South America, Canada and Africa.

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 :)

 
 



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.


 
 

 
 
 



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Arduino Boombox

Add sound or music to your project using the "Grove Serial MP3 Player".

An Arduino UNO will be used to control the Grove Serial MP3 player by sending it specific serial commands. The Grove Base Shield allows for the easy connection of Grove sensor modules to an Arduino UNO without the need for a breadboard. A sliding potentiometer, switch and button will be connected to the Base shield along with the Serial MP3 player. A specific function will be assigned to each of the connected sensor modules to provide a useful interface:

  • Sliding Potentiometer – Volume control
  • Button – Next Song
  • Switch – On/Off (toggle)
Once the MP3 module is working the way we want, we can then build a simple enclosure for it. Grab a shoe-box, print out your favourite design, and make your very own Arduino BOOMBOX!


 

Video

Watch the following video to see the project in action
 


 
 

Parts Required:

Optional components (for the BoomBox Enclosure):
  • Empty Shoe Box
  • Paper
  • Printer
  • Glue
If I had a 3D printer - I would have printed my own enclosure, but a shoebox seems to work just fine.


 

Putting it Together

Place the Grove Base shield onto the Arduino UNO,
and then connect each of the Grove Modules as per the table below.
 


 

If you do not have a Grove Base shield,
you can still connect the modules directly to the Arduino as per the table below:
 


 

When you are finished connecting the modules, it should look something like this:
  (ignore the battery pack):
 

As you can see from the picture above. You can cut holes out of the shoebox and stick the modules in place. Please ignore the battery pack, because you won't use it until after you have uploaded the Arduino code.


 
 

Arduino Sketch


 
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/* ===============================================================================
      Project: Grove Serial MP3 Player overview
       Author: Scott C
      Created: 9th March 2015
  Arduino IDE: 1.6.0
      Website: http://arduinobasics.blogspot.com/p/arduino-basics-projects-page.html

  Description: The following Arduino sketch will allow you to control a Grove Serial MP3 player
               with a Grove Sliding Potentiometer (volume), a Grove button (next song), 
               and a Grove Switch (on/off). It will also show you how to retrieve some useful information from the player. 
               Some functions are not used in this sketch,but have been included for your benefit. 
               
               Additional features and functionality can be found on the WT5001 voice chip datasheet 
               which I retrieved from here: http://goo.gl/ai6oQ9
               
               The Seeedstudio wiki was a very useful resource for getting started with the various Grove modules:
               http://goo.gl/xOiSCl
=============================================================================== */

#include <SoftwareSerial.h>
SoftwareSerial mp3(2, 3); // The Grove MP3 Player is connected to Arduino digital Pin 2 and 3 (Serial communication)
int potPin = A0; // The Sliding Potentiometer is connected to AnalogPin 0
int potVal = 0; // This is used to hold the value of the Sliding Potentiometer
byte mp3Vol = 0; // mp3Vol is used to calculate the Current volume of the Grove MP3 player
byte oldVol = 0; // oldVol is used to remember the previous volume level
int ledPin = A1; // The Grove sliding potentiometer has an onboard LED attached to Analog pin 1.

int switchPin = 12; // The Grove Switch(P) is connected to digital Pin 12
int switchStatus = 0; // This is used to hold the status of the switch
int switchChangeStatus = 0; // Used to identify when the switch status has changed

int buttonPin = 5; // The Grove Button is connected to digital pin 5
int buttonStatus = 0; // This is used to hold the status of the button



void setup(){
  //Initialise the Grove MP3 Module
  delay(2500);
  mp3.begin(9600);
  
        
  // initialize the pushbutton and switch pin as an input:
  pinMode(buttonPin, INPUT);
  pinMode(switchPin, INPUT);
  
  // set ledPin on the sliding potentiometer to OUTPUT
  pinMode(ledPin, OUTPUT);
  
  //You can view the following demostration output in the Serial Monitor
  demonstrate_GET_FUNCTIONS();     
}


void loop(){
  switchStatus = digitalRead(switchPin);
  if(switchStatus==HIGH){
    if(switchChangeStatus==LOW){ // When Arduino detects a change in the switchStatus (from LOW to HIGH) - play song
      setPlayMode(0x02);                     // Automatically cycle to the next song when the current song ends
      playSong(00,01);                       // Play the 1st song when you switch it on
      switchChangeStatus=HIGH;
    }
    
    potVal = analogRead(potPin); // Analog read values from the sliding potentiometer range from 0 to 1023
    analogWrite(ledPin, potVal/4); // Analog write values range from 0 to 255, and will turn LED ON once potentiometer reaches about half way (or more).
    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
    }

    buttonStatus = digitalRead(buttonPin);
    if(buttonStatus==HIGH){ // When a button press is detected - play the next song
      playNextSong();
      delay(200); // This delay aims to prevent a "skipped" song due to slow button presses - can modify to suit.
    }
  } else {
    if(switchChangeStatus==HIGH){ // When switchStatus changes from HIGH to LOW - stop Song.
      stopSong();
      switchChangeStatus=LOW;
    }
  } 
}


// demonstrate_GET_FUNCTIONS  will show you how to retrieve some useful information from the Grove MP3 Player (using the Serial Monitor).
void demonstrate_GET_FUNCTIONS(){
        Serial.begin(9600);
        Serial.print("Volume: ");
        Serial.println(getVolume());
        Serial.print("Playing State: ");
        Serial.println(getPlayingState());
        Serial.print("# of Files in SD Card:");
        Serial.println(getNumberOfFiles());
        Serial.println("------------------------------");
}


// writeToMP3: is a generic function that aims to simplify all of the methods that 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
  }
}


/* The Following functions control the Grove MP3 Player : see datasheet for additional functions--------------------------------------------*/

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);  
}


void playSong(byte songHbyte, byte songLbyte){ // Plays the selected song
  writeToMP3(0x04, 0xA0, songHbyte, songLbyte, 0x7E, 0x00, 0x00);            
}


void pauseSong(){ // Pauses the current song
  writeToMP3(0x02, 0xA3, 0x7E, 0x00, 0x00, 0x00, 0x00);
}


void stopSong(){ // Stops the current song
  writeToMP3(0x02, 0xA4, 0x7E, 0x00, 0x00, 0x00, 0x00);
}


void playNextSong(){ // Play the next song
  writeToMP3(0x02, 0xA5, 0x7E, 0x00, 0x00, 0x00, 0x00);
}


void playPreviousSong(){ // Play the previous song
  writeToMP3(0x02, 0xA6, 0x7E, 0x00, 0x00, 0x00, 0x00);
}


void addSongToPlayList(byte songHbyte, byte songLbyte){
  //Repeat this function for every song you wish to stack onto the playlist (max = 10 songs)
  writeToMP3(0x04, 0xA8, songHbyte, songLbyte, 0x7E, 0x00, 0x00);
}


void setVolume(byte Volume){ // Set the volume
  byte tempVol = constrain(Volume, 0, 31);
  //Volume range = 00 (muted) to 31 (max volume)
  writeToMP3(0x03, 0xA7, tempVol, 0x7E, 0x00, 0x00, 0x00); 
}



/* The following functions retrieve information from the Grove MP3 player : see data sheet for additional functions--------------*/

// getData: is a generic function to simplifly the other functions for retieving information from the Grove Serial MP3 player
byte getData(byte queryVal, int dataPosition){
  byte returnVal = 0x00;
  writeToMP3(0x02, queryVal, 0x7E, 0x00, 0x00, 0x00, 0x00);
  delay(50);
  for(int x = 0; x<dataPosition; x++){
    if(mp3.available()){
      returnVal = mp3.read();
      delay(50);
    }
  }
  return(returnVal);
}

byte getVolume(){ //Get the volume of the Grove Serial MP3 player
  //returns value from 0 - 31
  return(getData(0xC1, 4));
}

byte getPlayingState(){ //Get the playing state : Play / Stopped / Paused
  //returns 1: Play, 2: Stop, 3:Paused
  return(getData(0xC2, 2));
}


byte getNumberOfFiles(){ //Find out how many songs are on the SD card
  //returns the number of MP3 files on SD card
  return(getData(0xC4, 3));
}

You will notice from the code, that I did not utilise every function. I decided to include them for your benifit. 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.
 
IMPORTANT: You need to load your MP3 sounds or songs onto the SDHC card before you install it onto the Serial MP3 player.
 
Once the SDHC card is installed, and your code is uploaded to the Arduino, all you have to do now is connect the MP3 player to some headphones or a powered speaker. You can then power the Arduino and modules with a battery pack or some other portable power supply.
 
You can design and decorate the shoebox in any way you like. Just print out your picture, glue them on, and before you know it, you will have your very own Arduino Boombox.
 


Comments

I was very surprised by the quality of the sound that came from the MP3 module. It is actually quite good.

This tutorial was an introduction to the Grove Serial MP3 module in it's most basic form. You could just as easily use some other sensor to trigger the MP3 module. For example, you could get it to play an alert if a water leak was detected, or if a door was opened, or if the temperature got too high or too low. You could get it to play a reminder when you walk into your room. The possibilities are endless.

I really liked this module, and I am sure it will appear in a future tutorial.


 



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 Tutorials – Chapter 15 – RFID

Learn how to use RFID readers with your Arduino. In this instalment we use an RDM630 or RDM6300 RFID reader. If you have an Innovations ID-12 or ID-20 RFID reader, we have a different tutorial for you.

This is chapter fifteen of our huge Arduino tutorial seriesUpdated 19/11/2013

Introduction

RFID – radio frequency identification. Some of us have already used these things, and they have become part of everyday life. For example, with electronic vehicle tolling, door access control, public transport fare systems and so on. It sounds complex – but isn’t.

To explain RFID for the layperson, we can use a key and lock analogy. Instead of the key having a unique pattern, RFID keys hold a series of unique numbers which are read by the lock. It is up to our Arduino sketch to determine what happens when the number is read by the lock.  The key is the tag, card or other small device we carry around or have in our vehicles. We will be using a passive key, which is an integrated circuit and a small aerial. This uses power from a magnetic field associated with the lock. Here are some key or tag examples:

In this tutorial we’ll be using 125 kHz tags – for example. To continue with the analogy our lock is a small circuit board and a loop aerial. This has the capability to read the data on the IC of our key, and some locks can even write data to keys. Here is our reader (lock) example:

These readers are quite small and inexpensive – however the catch is that the loop aerial is somewhat fragile. If you need something much sturdier, consider the ID20 tags used in the other RFID tutorial.

Setting up the RFID reader

This is a short exercise to check the reader works and communicates with the Arduino. You will need:

Simply insert the RFID reader main board into a solderless breadboard as shown below. Then use jumper wires to connect the second and third pins at the top-left of the RFID board to Arduino 5V and GND respectively. The RFID coil connects to the two pins on the top-right (they can go either way). Finally, connect a jumper wire from the bottom-left pin of the RFID board to Arduino digital pin 2:

Next, upload the following sketch to your Arduino and open the serial monitor window in the IDE:

#include <SoftwareSerial.h>
SoftwareSerial RFID(2, 3); // RX and TX

int i;

void setup()
{
  RFID.begin(9600);    // start serial to RFID reader
  Serial.begin(9600);  // start serial to PC 
}

void loop()
{
  if (RFID.available() > 0) 
  {
     i = RFID.read();
     Serial.print(i, DEC);
     Serial.print(" ");
  }
}

If you’re wondering why we used SoftwareSerial – if you connect the data line from the RFID board to the Arduino’s RX pin – you need to remove it when updating sketches, so this is more convenient.

Now start waving RFID cards or tags over the coil. You will find that they need to be parallel over the coil, and not too far away. You can experiment with covering the coil to simulate it being installed behind protective surfaces and so on. Watch this short video which shows the resulting RFID card or tag data being displayed in the Arduino IDE serial monitor.

As you can see from the example video, the reader returns the card’s unique ID number which starts with a 2 and ends with a 3. While you have the sketch operating, read the numbers from your RFID tags and note them down, you will need them for future sketches.

To do anything with the card data, we need to create some functions to retrieve the card number when it is read and place in an array for comparison against existing card data (e.g. a list of accepted cards) so your systems will know who to accept and who to deny. Using those functions, you can then make your own access system, time-logging device and so on.

Let’s demonstrate an example of this. It will check if a card presented to the reader is on an “accepted” list, and if so light a green LED, otherwise light a red LED. Use the hardware from the previous sketch, but add a typical green and red LED with 560 ohm resistor to digital pins 13 and 12 respectively. Then upload the following sketch:

#include <SoftwareSerial.h>
SoftwareSerial RFID(2, 3); // RX and TX

int data1 = 0;
int ok = -1;
int yes = 13;
int no = 12;

// use first sketch in http://wp.me/p3LK05-3Gk to get your tag numbers
int tag1[14] = {2,52,48,48,48,56,54,66,49,52,70,51,56,3};
int tag2[14] = {2,52,48,48,48,56,54,67,54,54,66,54,66,3};
int newtag[14] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0}; // used for read comparisons

void setup()
{
  RFID.begin(9600);    // start serial to RFID reader
  Serial.begin(9600);  // start serial to PC 
  pinMode(yes, OUTPUT); // for status LEDs
  pinMode(no, OUTPUT);
}

boolean comparetag(int aa[14], int bb[14])
{
  boolean ff = false;
  int fg = 0;
  for (int cc = 0 ; cc < 14 ; cc++)
  {
    if (aa[cc] == bb[cc])
    {
      fg++;
    }
  }
  if (fg == 14)
  {
    ff = true;
  }
  return ff;
}

void checkmytags() // compares each tag against the tag just read
{
  ok = 0; // this variable helps decision-making,
  // if it is 1 we have a match, zero is a read but no match,
  // -1 is no read attempt made
  if (comparetag(newtag, tag1) == true)
  {
    ok++;
  }
  if (comparetag(newtag, tag2) == true)
  {
    ok++;
  }
}

void readTags()
{
  ok = -1;

  if (RFID.available() > 0) 
  {
    // read tag numbers
    delay(100); // needed to allow time for the data to come in from the serial buffer.

    for (int z = 0 ; z < 14 ; z++) // read the rest of the tag
    {
      data1 = RFID.read();
      newtag[z] = data1;
    }
    RFID.flush(); // stops multiple reads

    // do the tags match up?
    checkmytags();
  }

  // now do something based on tag type
  if (ok > 0) // if we had a match
  {
    Serial.println("Accepted");
    digitalWrite(yes, HIGH);
    delay(1000);
    digitalWrite(yes, LOW);

    ok = -1;
  }
  else if (ok == 0) // if we didn't have a match
  {
    Serial.println("Rejected");
    digitalWrite(no, HIGH);
    delay(1000);
    digitalWrite(no, LOW);

    ok = -1;
  }
}

void loop()
{
  readTags();
}

In the sketch we have a few functions that take care of reading and comparing RFID tags. Notice that the allowed tag numbers are listed at the top of the sketch, you can always add your own and more – as long as you add them to the list in the function checkmytags() which determines if the card being read is allowed or to be denied.

The function readTags() takes care of the actual reading of the tags/cards, by placing the currently-read tag number into an array which is them used in the comparison function checkmytags(). Then the LEDs are illuminated depending on the status of the tag at the reader. You can watch a quick demonstration of this example in this short video.

Conclusion

After working through this chapter you should now have a good foundation of knowledge on using the inexpensive RFID readers and how to call functions when a card is successfully read. For example, use some extra hardware (such as an N-MOSFET) to control a door strike, buzzer, etc. Now it’s up to you to use them as a form of input with various access systems, tracking the movement of people or things and much more.

And if you enjoyed the tutorial, or want to introduce someone else to the interesting world of Arduino – check out my book (now in a third printing!) “Arduino Workshop” from No Starch Press.

In the meanwhile have fun and keep checking into tronixstuff.com. Why not follow things on twitterGoogle+, subscribe  for email updates or RSS using the links on the right-hand column? And join our friendly Google Group – dedicated to the projects and related items on this website. Sign up – it’s free, helpful to each other –  and we can all learn something.

The post Arduino Tutorials – Chapter 15 – RFID appeared first on tronixstuff.

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