Step Sequencer

Made by ArtisLab / Art / Music / Retro Tech

About the project

Step Sequencer is a small expansion board for Arduino Uno that realizes a six-stage step sequencer producing 8-bit tone sequences.

Project info

Difficulty: Easy

Platforms: Arduino

Estimated time: 2 hours

License: GNU General Public License, version 3 or later (GPL3+)

Items used in this project

Hardware components

	2.54mm 0.1" 20-pin Dual Row Male Header	x 1
	Rotary Potentiometer Module	x 6
	Resistor Network - 10k Ohm (6-pin Bussed)	x 1
	This Is A Simple Spdt Slide Switch - Great For Use As An On/off Button Or Just As A General Control Switch. The Pins Are Spaced By 0.1" However They Are Incredibly Thin Making Breadboard Use Not Recommended. The Switch Is Rated For 0.3a At 50vdc.	x 1
	Genuino Uno Rev3	x 1

Hand tools and fabrication machines

Soldering iron (generic)

x 1

Story

The Step Sequencer shield is the first project made by Artis Lab in the spring 2016. The board is an expansion for Arduino Uno that realizes a six-stage step sequencer producing 8-bit tone sequences.

This small device has been specially created to be used inside Oracolo a sound object by Costantino Rizzuti.

Oracolo

The code to program the step sequencer is available in our tutorial: How to program a step sequencer with Arduino.

Here our project's main page

Some videos showing how to make sounds with Oracolo:

Schematics, diagrams and documents

StepSequencer Skematic

The circuit schematic for the step sequencer

StepSequencer Circuit

The circuit diagram for the step sequencer

Code

StepSequencer-ShieldOracolo.ino

This code allows to realize a step sequencer using an Arduino Uno board.

/*
  ++ 6 STEP SEQUENCER ++
 
  DESCRIPTION:
  Reads values from 6 potentiometers to change the pitch of any step of the sequencer tone generator.
  Change the pitch of each step with a potentiometer.
    
  CIRCUIT:
  Connect a speaker or piezo to pin number 13 and to ground;
  Connect the first lead of a potentiometer to 5v and the last to ground, the one in the middle to Analog Input pin 0;
  (Repeat for all the four potentiometers connecting the middle lead to Analog Input pins 0, 1, 2, 3, 4, 5);
  Connect a switch from digital port 3 and ground, put a 220 Ohm Resistor between the digital port 3 and 5V;

  For more information follow this link: http://www.artislab.it/it/step-sequencer/
 
  This example code is for educational purpose and it is in the public domain.
  Author: Costantino Rizzuti 2016
  Derived by a previous sketch made by Alessandro Contini & Paolo Cavagnolo
  
*/

// Tones table definition
#define NOTE_B0  31
#define NOTE_C1  33
#define NOTE_CS1 35
#define NOTE_D1  37
#define NOTE_DS1 39
#define NOTE_E1  41
#define NOTE_F1  44
#define NOTE_FS1 46
#define NOTE_G1  49
#define NOTE_GS1 52
#define NOTE_A1  55
#define NOTE_AS1 58
#define NOTE_B1  62
#define NOTE_C2  65
#define NOTE_CS2 69
#define NOTE_D2  73
#define NOTE_DS2 78
#define NOTE_E2  82
#define NOTE_F2  87
#define NOTE_FS2 93
#define NOTE_G2  98
#define NOTE_GS2 104
#define NOTE_A2  110
#define NOTE_AS2 117
#define NOTE_B2  123
#define NOTE_C3  131
#define NOTE_CS3 139
#define NOTE_D3  147
#define NOTE_DS3 156
#define NOTE_E3  165
#define NOTE_F3  175
#define NOTE_FS3 185
#define NOTE_G3  196
#define NOTE_GS3 208
#define NOTE_A3  220
#define NOTE_AS3 233
#define NOTE_B3  247
#define NOTE_C4  262
#define NOTE_CS4 277
#define NOTE_D4  294
#define NOTE_DS4 311
#define NOTE_E4  330
#define NOTE_F4  349
#define NOTE_FS4 370
#define NOTE_G4  392
#define NOTE_GS4 415
#define NOTE_A4  440
#define NOTE_AS4 466
#define NOTE_B4  494
#define NOTE_C5  523
#define NOTE_CS5 554
#define NOTE_D5  587
#define NOTE_DS5 622
#define NOTE_E5  659
#define NOTE_F5  698
#define NOTE_FS5 740
#define NOTE_G5  784
#define NOTE_GS5 831
#define NOTE_A5  880
#define NOTE_AS5 932
#define NOTE_B5  988
#define NOTE_C6  1047
#define NOTE_CS6 1109
#define NOTE_D6  1175
#define NOTE_DS6 1245
#define NOTE_E6  1319
#define NOTE_F6  1397
#define NOTE_FS6 1480
#define NOTE_G6  1568
#define NOTE_GS6 1661
#define NOTE_A6  1760
#define NOTE_AS6 1865
#define NOTE_B6  1976
#define NOTE_C7  2093
#define NOTE_CS7 2217
#define NOTE_D7  2349
#define NOTE_DS7 2489
#define NOTE_E7  2637
#define NOTE_F7  2794
#define NOTE_FS7 2960
#define NOTE_G7  3136
#define NOTE_GS7 3322
#define NOTE_A7  3520
#define NOTE_AS7 3729
#define NOTE_B7  3951
#define NOTE_C8  4186
#define NOTE_CS8 4435
#define NOTE_D8  4699
#define NOTE_DS8 4978


// Declaration of tones used in the sequencer
// Define here the note you want to play.
// The first notes are mapped to the lowest position of the pots
int pitch[] = { 
                NOTE_C3,
                NOTE_GS3,
                NOTE_CS3,
                NOTE_AS3,
                NOTE_A3,
                NOTE_B3,
                NOTE_F4,
                NOTE_DS4,
                NOTE_E4,
                NOTE_G3,
                NOTE_D4,
                NOTE_FS4};
                
                
// Declaration of variables               
int speaker = 9;                          // Speaker output pin
int k=0;                                     // Variable to store the value of the loop   
int POT1 = A0;                              // POT1 pin
int POT2 = A1;                              // POT2 pin
int POT3 = A2;                              // POT3 pin
int POT4 = A3;                              // POT4 pin
int POT5 = A4;                              // POT5 pin
int POT6 = A5;                              // POT6 pin
int ReadPot1,ReadPot2,ReadPot3,ReadPot4,ReadPot5,ReadPot6;                            // Variable to store the value of the pots
// Variables used to calculate tempo
// set BPM
int bpm=180;
// set Subdivision 1=quarter note; 0.5 ->eight note, ....
float subdivision=1;
//Define here the sequence of durations
//-> 1->quarter note; 0.5 ->eight note, ....
float D[] = {1, 0.5, 0.5, 0.333, 0.333, 0.333}; //3/4 pattern
//float D[] = {1, 0.5, 0.5, 1,0.5, 0.5}; //4/4 pattern
// The lenght of the D array
int NDuration=6;  
int DurCount=0;                               
int value[] = {0, 0, 0, 0, 0, 0};              // value to define the discrete interval of tune using the pot
int note[] = {0, 0, 0, 0, 0, 0};  
int interval; 

void setup() {
    pinMode(3, INPUT);
    //Period computed according bpm and subdivision
    interval = 60000/(subdivision*bpm);  
}


void loop() { 
   if(digitalRead(3)==HIGH){
    for (k = 0; k <= 5; k++) {                                 // Cycle on each pot
      value[k] = map(analogRead(k), 0, 1023, 0, 2500);         // Mapping the value of the Potentiometer to have a wider range of values
      
      if ((value[k]>=0) && (value[k]<100))                     // Discretization of the pot intervals - in order to assign the note
        note[k] = 0;    
      if ((value[k]>=100) && (value[k]<300))
        note[k] = pitch[0];
      if ((value[k]>=300) && (value[k]<500))
        note[k] = pitch[1];
      if ((value[k]>=500) && (value[k]<700))
        note[k] = pitch[2];
      if ((value[k]>=700) && (value[k]<900))
        note[k] = pitch[3];
      if ((value[k]>=900) && (value[k]<1100))
        note[k] = pitch[4];
      if ((value[k]>=1100) && (value[k]<1300))
        note[k] = pitch[5];
      if ((value[k]>=1300) && (value[k]<1500))
        note[k] = pitch[6];
      if ((value[k]>=1500) && (value[k]<1700))
        note[k] = pitch[7];
      if ((value[k]>=1700) && (value[k]<=1900))
        note[k] = pitch[8];
      if ((value[k]>=1900) && (value[k]<=2100))
        note[k] = pitch[9];
      if ((value[k]>=2100) && (value[k]<=2300))
        note[k] = pitch[10];  
      if ((value[k]>=2300) && (value[k]<=2500))
        note[k] = pitch[11];       

      float Duration=D[DurCount]*interval;
      tone(speaker, note[k], Duration);           // Play the note
      DurCount++;
      if(DurCount>=NDuration)DurCount=0;    
      
      delay(Duration);
    }
   }
}

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