Microchip Technology Inc – MCP4131

Features:

-7-bit: 128 Resistors with 129 Taps to VSS and VDD
-SPI compatible interface
-Automatic Recall of Potentiometer Wiper Settings Resistance Values: 5k Ohm, 10k Ohm, 50k Ohm, 100k Ohm
-Absolute (Rheostat): <100 ppm (typ.) -Ratiometric (Potentiometer): <10 ppm (typ.) Device Overview – Summary

The MCP41/423X devices are volatile, 7-bit (129 wiper steps) digital potentiometers with an SPI compatible interface. The MCP41/42XX family is available with end-to-end resistor values of 5K Ohm, 10K Ohm, 50k Ohm and 100K Ohm. These devices offer a variety of configurations simplifying design while minimizing cost, package size and pin count.

Additional Features

-7-bit: 128 Resistors with 129 Taps to VSS and VDD
-SPI compatible interface
-Automatic Recall of Potentiometer Wiper Settings Resistance Values: 5k Ohm, 10k Ohm, 50k Ohm, 100k Ohm
-Low Tempco: Absolute (Rheostat): <100 ppm (typ.) -Ratiometric (Potentiometer): <10 ppm (typ.) -Low Wiper Resistance: 100 Ohm (typ.) -Low-Power Operation: 1µA Max Static Current -Wide Operating Voltage: 1.8V to 5.5V -Extended Temperature Range: -40°C to +125°C MCP4131 – Digital Potentiometer – 10K

Potentiometers are incredibly useful, whether you’re controlling the volume on your stereo or the ‘mood lighting’ in your room. The problem with traditional potentiometers is the fact that your microcontroller doesn’t have an easy way to interface with them. Digital potentiometers solve that problem by allowing you to control a voltage splitter with digital signals.

Wire it up just like a potentiometer and use serial signals to ‘turn the knob’. Another handy feature of digital potentiometers is that because they aren’t controlled mechanically, they don’t have a pre-determined sweep profile. In other words, depending on the way you write your code the potentiometer can ‘sweep’ in a linear fashion, a logarithmic fashion, or according to any other profile you like. Digital potentiometers can also be used in conjunction with rotary encoders to consolidate large banks of potentiometers into one ‘smart’ rotary control.

Digital Potentiometer MCP41131 and Arduino

We know the analog potentiometer, is a three-terminal resistor with a sliding contact that forms an adjustable voltage divider. Potentiometers many application such like:

1- Volume controls on audio equipment
2- Control the amplifier gain and offset
3- Transducer displacement transducers

Many other application, but did you want to control the resistance value by Arduino instead of using analog one. Analog potentiometers have some problem with Arduino doesn’t have an easy way to interface with them. The digital potentiometer, give you an ability to adjust the resistance, allowing you to control a voltage splitter with digital signals. This IC using SPI Protocol to communicate with Arduino.

DonLuc1808Mk03

1 x RGB LCD Shield 16×2 Character Display
1 x Arduino UNO – R3
1 x ProtoScrewShield
1 x MCP4131
1 x LED Green
1 x 270 Ohm Resistance
1 x NeoPixel Stick – 8 x 5050 RGB LED
1 x 100K Potentiometer
1 x Black Knob
7 x Jumper Wires 3″ M/M
12 x Jumper Wires 6″ M/M
1 x Full-Size Breadboard
1 x USB Cable A to B

Arduino UNO

MC1 – Digital 13
MC2 – Digital 11
MC3 – Digital 10
LR1 – Digital 3
POT – Analog 1
GND – GND
VIN – +5V

DonLuc1808Mk03p.ino

// ***** Don Luc Electronics *****
// Software Version Information
// Project #7: RGB LCD Shield – MCP4131 – Mk10
// 8-03
// DonLuc1808Mk03p 8-03
// RGB LCD Shield
// MCP4131

// Include Library Code
#include <Adafruit_MCP23017.h>
#include <Adafruit_RGBLCDShield.h>
#include <Adafruit_NeoPixel.h>
#include <SPI.h>

// RGB LCD Shield
Adafruit_RGBLCDShield RGBLCDShield = Adafruit_RGBLCDShield();
#define GREEN 0x2

// NeoPixels
#define PIN 3                             // On digital pin 3
#define NUMPIXELS 8                       // NeoPixels NUMPIXELS = 8
Adafruit_NeoPixel pixels = Adafruit_NeoPixel(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);
int red = 0;                              // Red
int green = 0;                            // Green
int blue = 0;                             // Blue
int iNeo = 0;                             // Neopix
const int iBriPin = A1;                   // Panel Mount 1K potentiometer Brightneed
int iBri = 0;                             // Neopix Brightness
int iBriMin = 1023;                       // Brightneed minimum sensor value
int iBriMax = 0;                          // Brightneed maximun sensor value
int z = 0;                                // Value

// MCP4131
int pinCS = 10;                           // MCP4131
byte address = 0x00;                      // Address
int i = 0;                                // Value

void loop() 
{

  // MCP4131
  isMCP4131();

  delay(1000);
  
  // Clear
  RGBLCDShield.clear();
  
}

getMCP4131.ino

// MCP4131
void isMCP4131()
{

  // NeoPixels
  isNUMPIXELSoff();                             // isNUMPIXELSoff
  
  // Display
  // Set the cursor to column 0, line 0  
  RGBLCDShield.setCursor(0,0);
  RGBLCDShield.print("MCP4131");                // MCP4131

  // MCP4131
  // Move the potentiometer in one direction
  for ( i = 0; i <= 128; i++) 
  {

    isNUMPIXELSoff();                           // isNUMPIXELSoff
    
    MCP4131PotWrite(i);

    isNUMPIXELS();                              // isNUMPIXELS
        
    delay(100);
    
    // Set the cursor to column 0, line 1
    RGBLCDShield.setCursor(0, 1); 
    RGBLCDShield.print("Level = ");             // MCP4131
    RGBLCDShield.print(i);                      // MCP4131 

  }
  
  delay(2000);  // wait a couple seconds
  
  // Now mover potentiometer in other directions  
  for ( i = 128; i >= 0; i--) 
  {

    isNUMPIXELSoff();                            // isNUMPIXELSoff
    
    MCP4131PotWrite(i);

    isNUMPIXELS();                               // isNUMPIXELS
        
    delay(100);
    
    RGBLCDShield.setCursor(0, 1);
    RGBLCDShield.print("                ");
    RGBLCDShield.setCursor(0, 1); 
    RGBLCDShield.print("Level =  ");             // MCP4131    
    RGBLCDShield.print(i);                       // MCP4131 

  }
  
  delay(2000);

}
// MCP4131PotWrite
int MCP4131PotWrite(int value)
{
  
  digitalWrite(pinCS, LOW);                      // pinCS Off
  SPI.transfer(address);                         // SPI Address
  SPI.transfer(value);                           // SPI Value
  digitalWrite(pinCS, HIGH);                     // pinCS On
  
}

neopix.ino

// NeoPixels
void neopix() 
{ 
    
    // Brightness
    iBri = analogRead(iBriPin);

    // iBri apply the calibration to the sensor reading
    iBri = map(iBri, iBriMin, iBriMax, 0, 255);

    // iBri in case the sensor value is outside the range seen during calibration
    iBri = constrain(iBri, 0, 255);
    
    pixels.setBrightness( iBri );
    // Pixels.Color takes RGB values, from 0,0,0 up to 255,255,255
    pixels.setPixelColor( iNeo, pixels.Color(red,green,blue) ); 
    // This sends the updated pixel color to the hardware
    pixels.show(); 
    // Delay for a period of time (in milliseconds)
    delay(50);     
  
}
// isNUMPIXELS
void isNUMPIXELS()
{

  // Neopix Value
  z = ( i / 16 );                             // Value
  
  // Neopix Value
  switch ( z ) {  
    case 0:
      // NeoPixels
      // Green
      for(int y=0; y<=0; y++)
      { 
         red = 0;                             // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      break;  
    case 1:
      // Green
      // NeoPixels
      for(int y=0; y<=1; y++){ 
         red = 0;                             // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      break;
    case 2:
      // NeoPixels
      // Green
      for(int y=0; y<=2; y++){ 
         red = 0;                             // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      break;
    case 3:
      // NeoPixels
      // Green
      for(int y=0; y<=2; y++){ 
         red = 0;                             // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      // Yellow
      for(int y=3; y<=3; y++){ 
         red = 255;                           // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      break;
    case 4:
      // NeoPixels
      // Green
      for(int y=0; y<=2; y++){ 
         red = 0;                             // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      // Yellow
      for(int y=3; y<=4; y++){ 
         red = 255;                           // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      break;
    case 5:
      // NeoPixels
      // Green
      for(int y=0; y<=2; y++){ 
         red = 0;                             // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      // Yellow
      for(int y=3; y<=5; y++){ 
         red = 255;                           // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      break;
    case 6:
      // NeoPixels
      // Green
      for(int y=0; y<=2; y++){ 
         red = 0;                             // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      // Yellow
      for(int y=3; y<=5; y++){ 
         red = 255;                           // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      // Red
      for(int y=6; y<=6; y++){ 
         red = 255;                           // Red
         green = 0;                           // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }      
      break;
    case 7:
      // NeoPixels
      // Green
      for(int y=0; y<=2; y++){ 
         red = 0;                             // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      // Yellow
      for(int y=3; y<=5; y++){ 
         red = 255;                           // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      // Red
      for(int y=6; y<=7; y++){ 
         red = 255;                           // Red
         green = 0;                           // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }      
      break;
    case 8:
      // NeoPixels
      // Green
      for(int y=0; y<=2; y++){ 
         red = 0;                             // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      // Yellow
      for(int y=3; y<=5; y++){ 
         red = 255;                           // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      // Red
      for(int y=6; y<=7; y++){ 
         red = 255;                           // Red
         green = 0;                           // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }      
      break; 
  }
      
}
// isNUMPIXELSoff
void isNUMPIXELSoff()
{

   // Black
   // NeoPixels
   for(int y=0; y < NUMPIXELS; y++)
   { 
      red = 0;                                 // Red
      green = 0;                               // Green
      blue = 0;                                // Blue
      iNeo = y;                                // Neopix  
      neopix();    
   }
   
}

setup.ino

// Setup
void setup() 
{

  // set up the LCD's number of columns and rows: 
  RGBLCDShield.begin(16, 2);
  RGBLCDShield.setBacklight(GREEN);
  
  // Display
  // Set the cursor to column 0, line 0  
  RGBLCDShield.setCursor(0,0);  
  RGBLCDShield.print("Don Luc");           // Don luc
  // Set the cursor to column 0, line 1
  RGBLCDShield.setCursor(0, 1);
  RGBLCDShield.print("MCP4131");           // MCP4131
  delay(5000);

  // Clear
  RGBLCDShield.clear();

  // NeoPixels
  pixels.begin();                          // This initializes the NeoPixel library
  // NeoPixels
  isNUMPIXELSoff();                        // isNUMPIXELSoff
  
  // MCP4131
  pinMode(pinCS, OUTPUT);                  // MCP4131 OUTPUT
  
  SPI.begin();                             // SPI
    
}

Don Luc

Rotary Switch – 10 Position

This is a single pole, 10 position rotary switch able to select up to 10 different states in a durable package. Unlike our other rotary switch, this model is much more robust and capable of handling larger currents and voltages.

With a max voltage rating of 125VAC at 0.3A and a dielectric strength of 250VAC for 1 minute this is a serious little rotary switch capable of working with some of your bigger projects. Though this switch requires you to use 11 pins and is not breadboard friendly we do offer a breakout board (found in the Recommended Products section below) to provide easier access to its capabilities.

1 x Rotary Switch – 10 Position
1 x Hex Nut
2 x Washer

Rating: 0.3A/125VAC
Contact Resistance: 50M Ohm max
Insulation Resistance: 100M Ohm @ 500VDC min
Dielectric Strength: 250VAC for 1 minute
Rotation torque: 1.0+0.5KG/cm
Shaft: 3/8″

Rotary Switch Breakout

This is the SparkFun Rotary Switch Breakout, a very simple board designed to easily provide you access to each pin on our 10-position rotary switches. This breakout allows you to easily add a rotary switch to your next project without having to worry about attaching its unique footprint to a custom board or solderless breadboard. All you need to do is solder the 10-position rotary switch into the breakout (using the silkscreen on the board as a guide) and each pin will become available for breadboard or hookup wire compatibility.

Each one of these boards breaks out the common ( C ), 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 positions on the board into 0.1″ spaced pins.

NeoPixel Stick – 8 x 5050 RGB LED

Make your own little LED strip arrangement with this stick of NeoPixel LEDs. We crammed 8 of the tiny 5050 (5mm x 5mm) smart RGB LEDs onto a PCB with mounting holes and a chainable design. Use only one microcontroller pin to control as many as you can chain together! Each LED is addressable as the driver chip is inside the LED. Each one has ~18mA constant current drive so the color will be very consistent even if the voltage varies, and no external choke resistors are required making the design slim. Power the whole thing with 5VDC (4-7V works) and you’re ready to rock.

DonLuc1808Mk01

1 x RGB LCD Shield 16×2 Character Display
1 x Arduino UNO – R3
1 x ProtoScrewShield
1 x Rotary Switch – 10 Position
1 x Rotary Switch Breakout
1 x Black Knob
1 x NeoPixel Stick – 8 x 5050 RGB LED
1 x 100K Potentiometer
1 x Black Knob
11 x 1K Ohm Resistance
17 x Jumper Wires 3″ M/M
6 x Jumper Wires 6″ M/M
1 x Size Breadboard
1 x USB Cable A to B

Arduino UNO

NEO – Digital 0
ROT – Analog 1
POT – Analog 0
GND – GND
VIN – +5V

DonLuc1808Mk01p.ino

// ***** Don Luc *****
// Software Version Information
// Project #7: RGB LCD Shield – Rotary Switch – Mk08
// 8-01
// DonLuc1808Mk01p 8-01
// RGB LCD Shield
// Rotary Switch

// Include Library Code
#include <Adafruit_MCP23017.h>
#include <Adafruit_RGBLCDShield.h>
#include <Adafruit_NeoPixel.h>

// RGB LCD Shield
Adafruit_RGBLCDShield RGBLCDShield = Adafruit_RGBLCDShield();
#define GREEN 0x2

// NeoPixels
#define PIN 0                             // On digital pin 3
#define NUMPIXELS 8                       // NeoPixels NUMPIXELS = 8
Adafruit_NeoPixel pixels = Adafruit_NeoPixel(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);
int red = 0;                              // Red
int green = 0;                            // Green
int blue = 0;                             // Blue
int iNeo = 0;                             // Neopix
const int iBriPin = A0;                   // Panel Mount 1K potentiometer Brightneed
int iBri = 0;                             // Neopix Brightness
int iBriMin = 1023;                       // Brightneed minimum sensor value
int iBriMax = 0;                          // Brightneed maximun sensor value

// Rotary Switch
// Rotary Switch - 10 Position
// Number = 1 => 10
int iRotNum = A1;                         // Rotary Switch
int iVal = 0;                             // iVal - Value            
int z = 0;                                // Number

void loop() 
{

  // Rotary Switch
  isRot();

  delay(1000);
  
  // Clear
  RGBLCDShield.clear();
  
}

getRot.ino

// Rotary Switch
void isRot()
{

  // NeoPixels
  for(int y=0; y < NUMPIXELS; y++)
  { 
     // Black
     red = 0;                                 // Red
     green = 0;                               // Green
     blue = 0;                                // Blue
     iNeo = y;                                // Neopix  
     neopix();    
  }
   
  // Display
  // Set the cursor to column 0, line 0  
  RGBLCDShield.setCursor(0,0);
  RGBLCDShield.print("Rotary Switch");        // Rotary Switch

  // Rotary Switch
  z = analogRead( iRotNum );                  // Rotary Switch
  iVal = ( z / 100 );                         // Rotary Value
   
  // Set the cursor to column 0, line 1
  RGBLCDShield.setCursor(0, 1); 
  RGBLCDShield.print("iVal = ");              // Rotary Value
  RGBLCDShield.print( iVal + 1 );

  // Range Value
  switch ( iVal ) {
    case  0:
      // Red
      // NeoPixels
      for(int y=0; y<NUMPIXELS; y++){ 
         red = 255;                           // Red
         green = 0;                           // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }        
      break;
    case 1:
      // Green
      // NeoPixels
      for(int y=0; y<NUMPIXELS; y++){ 
         red = 0;                             // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      break;
    case 2:
      // Blue
      // NeoPixels
      for(int y=0; y<NUMPIXELS; y++){ 
         red = 0;                             // Red
         green = 0;                           // Green
         blue = 255;                          // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      break;
    case 3:
      // White
      // NeoPixels
      for(int y=0; y<NUMPIXELS; y++){ 
         red = 255;                           // Red
         green = 255;                         // Green
         blue = 255;                          // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      break;  
    case 4:
      // NeoPixels
      // Red
      for(int y=0; y<NUMPIXELS; y++){ 
         red = 255;                           // Red
         green = 0;                           // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      delay( 2000 );
      // Green
      for(int y=0; y<NUMPIXELS; y++){ 
         red = 0;                             // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      delay( 2000 );
      // Blue
      for(int y=0; y<NUMPIXELS; y++){ 
         red = 0;                             // Red
         green = 0;                           // Green
         blue = 255;                          // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }          
      break;
    case 5:
      // NeoPixels
      // Yellow
      for(int y=0; y<NUMPIXELS; y++){ 
         red = 255;                           // Red
         green = 255;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      } 
      break;
    case 6:
      // NeoPixels
      // Orange
      for(int y=0; y<NUMPIXELS; y++){ 
         red = 255;                           // Red
         green = 102;                         // Green
         blue = 0;                            // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      break;       
    case 7:
      // NeoPixels
      // Violet
      for(int y=0; y<NUMPIXELS; y++){ 
         red = 204;                           // Red
         green = 102;                         // Green
         blue = 204;                          // Blue
         iNeo = y;                            // Neopix      
         neopix(); 
      }
      break; 
    case 8:
      // NeoPixels
      // Red
      red = 255;                           // Red
      green = 0;                           // Green
      blue = 0;                            // Blue
      iNeo = 0;                            // Neopix      
      neopix();
      delay( 1000 );
      // Green
      red = 0;                             // Red
      green = 255;                         // Green
      blue = 0;                            // Blue
      iNeo = 1;                            // Neopix      
      neopix();
      delay( 1000 ); 
      // Blue
      red = 0;                             // Red
      green = 0;                           // Green
      blue = 255;                          // Blue
      iNeo = 2;                            // Neopix      
      neopix();
      delay( 1000 );
      // White
      red = 255;                           // Red
      green = 255;                         // Green
      blue = 255;                          // Blue
      iNeo = 3;                            // Neopix      
      neopix();
      delay( 1000 );
      // Pink
      red = 255;                           // Red
      green = 153;                         // Green
      blue = 203;                          // Blue
      iNeo = 4;                            // Neopix      
      neopix();
      delay( 1000 );
      // Orange
      red = 255;                           // Red
      green = 102;                         // Green
      blue = 0;                            // Blue
      iNeo = 5;                            // Neopix      
      neopix();
      delay( 1000 ); 
      // Violet
      red = 204;                           // Red
      green = 102;                         // Green
      blue = 204;                          // Blue
      iNeo = 6;                            // Neopix      
      neopix();
      delay( 1000 ); 
      // Yellow
      red = 255;                           // Red
      green = 255;                         // Green
      blue = 0;                            // Blue
      iNeo = 7;                            // Neopix      
      neopix();
      delay( 1000 );         
      break; 
    case 9:
      // NeoPixels
      // Red
      red = 255;                           // Red
      green = 0;                           // Green
      blue = 0;                            // Blue
      iNeo = 7;                            // Neopix      
      neopix();
      delay( 1000 );
      // Green
      red = 0;                             // Red
      green = 255;                         // Green
      blue = 0;                            // Blue
      iNeo = 6;                            // Neopix      
      neopix();
      delay( 1000 ); 
      // Blue
      red = 0;                             // Red
      green = 0;                           // Green
      blue = 255;                          // Blue
      iNeo = 5;                            // Neopix      
      neopix();
      delay( 1000 );
      // White
      red = 255;                           // Red
      green = 255;                         // Green
      blue = 255;                          // Blue
      iNeo = 4;                            // Neopix      
      neopix();
      delay( 1000 );
      // Pink
      red = 255;                           // Red
      green = 153;                         // Green
      blue = 203;                          // Blue
      iNeo = 3;                            // Neopix      
      neopix();
      delay( 1000 );
      // Orange
      red = 255;                           // Red
      green = 102;                         // Green
      blue = 0;                            // Blue
      iNeo = 2;                            // Neopix      
      neopix();
      delay( 1000 ); 
      // Violet
      red = 204;                           // Red
      green = 102;                         // Green
      blue = 204;                          // Blue
      iNeo = 1;                            // Neopix      
      neopix();
      delay( 1000 ); 
      // Yellow
      red = 255;                           // Red
      green = 255;                         // Green
      blue = 0;                            // Blue
      iNeo = 0;                            // Neopix      
      neopix();
      delay( 1000 );
      break;
  }

}

neopix.ino

// NeoPixels
void neopix() { 
    
    // Brightness
    iBri = analogRead(iBriPin);

    // iBri apply the calibration to the sensor reading
    iBri = map(iBri, iBriMin, iBriMax, 0, 255);

    // iBri in case the sensor value is outside the range seen during calibration
    iBri = constrain(iBri, 0, 255);
    
    pixels.setBrightness( iBri );
    // Pixels.Color takes RGB values, from 0,0,0 up to 255,255,255
    pixels.setPixelColor( iNeo, pixels.Color(red,green,blue) ); 
    // This sends the updated pixel color to the hardware
    pixels.show(); 
    // Delay for a period of time (in milliseconds)
    delay(50);     
  
}

setup.ino

// Setup
void setup() 
{

  // set up the LCD's number of columns and rows: 
  RGBLCDShield.begin(16, 2);
  RGBLCDShield.setBacklight(GREEN);
  
  // Display
  // Set the cursor to column 0, line 0  
  RGBLCDShield.setCursor(0,0);  
  RGBLCDShield.print("Don Luc");           // Don luc
  // Set the cursor to column 0, line 1
  RGBLCDShield.setCursor(0, 1);
  RGBLCDShield.print("Rotary Switch");     // Rotary Switch
  delay(5000);

  // Clear
  RGBLCDShield.clear();

  // NeoPixels
  pixels.begin();          // This initializes the NeoPixel library
  // NeoPixels
  
  for(int y=0; y < NUMPIXELS; y++)
  { 
     // Black
     red = 0;                                 // Red
     green = 0;                               // Green
     blue = 0;                                // Blue
     iNeo = y;                                // Neopix  
     neopix();    
  }

}

Don Luc

Line Sensor Breakout – QRE1113 (Analog)

Description

This version of the QRE1113 breakout board features an easy-to-use analog output, which will vary depending on the amount of IR light reflected back to the sensor. This tiny board is perfect for line sensing applications and can be used in both 3.3V and 5V systems.

The board’s QRE1113 IR reflectance sensor is comprised of two parts – an IR emitting LED and an IR sensitive phototransistor. When you apply power to the VCC and GND pins the IR LED inside the sensor will illuminate. A 100 Ohm resistor is on-board and placed in series with the LED to limit current. A 10k Ohm resistor pulls the output pin high, but when the light from the LED is reflected back onto the phototransistor the output will begin to go lower. The more IR light sensed by the phototransistor, the lower the output voltage of the breakout board.

These sensors are widely used in line following robots – white surfaces reflect much more light than black, so, when directed towards a white surface, the voltage output will be lower than that on a black surface.

The power input and analog output pins are brought out to a 3-pin, 0.1″ pitch header. The board also has a single mounting hole if you want to screw the board onto something.

Features

* 5VDC operating voltage
* 25mA supply current
* Optimal sensing distance: 0.125″ (3mm)
* 0.30 x 0.55 “ (7.62 x 13.97 mm)

Common Reflectance Sensor

The QRE1113 is a common reflectance sensor often used in robotic line followers. The sensor works by shining an IR LED down and seeing how much of that light bounces back using a phototransistor. Because dark colors will bounce back less of the light, the sensor can be used to tell the difference between white and black areas. So an array of these can be used to help a robot determine where a dark line is on the ground so it can follow it. But they can also be used to determine proximity under an inch.

The an analog input on your microcontroller but still need an analog reading of how much light was reflected. It does this by allowing you to charge a capacitor on the board, and then timing how long it takes to discharge. The more light that is reflected, the less time it takes to discharge the capacitor. Hooking the QRE1113 to your Arduino is very simple. It just needs power (5V), ground, and an analog pin.

DonLuc1807Mk11

1 x RGB LCD Shield 16×2 Character Display
1 x Arduino UNO – R3
1 x ProtoScrewShield
1 x Line Sensor Breakout – QRE1113 (Analog)
3 x Jumper Wires 6″ M/M
1 x Half-Size Breadboard

Arduino UNO

CRS – Analog 0
GND – GND
VIN – +5V

DonLuc1807Mk11p.ino

// ***** Don Luc *****
// Software Version Information
// Project #7: RGB LCD Shield – Line Sensor Breakout – Mk07
// 7-11
// DonLuc1807Mk10p 7-11
// RGB LCD Shield
// QRE1113 (Analog)

// include the library code:
#include <Adafruit_MCP23017.h>
#include <Adafruit_RGBLCDShield.h>

Adafruit_RGBLCDShield RGBLCDShield = Adafruit_RGBLCDShield();
#define GREEN 0x2

// Seven-Segment Display
int iQRE1113 = A0;       // iQRE1113
int iQRE1113Value = 0;   // iQRE1113Value

void loop() 
{

  // QRE1113 (Analog)
  isCRS();

  delay(2000);
  
  // Clear
  RGBLCDShield.clear();
  
}

getSeven.ino

// Line Sensor Breakout - QRE1113
void isCRS()
{

  // Display
  // Set the cursor to column 0, line 0  
  RGBLCDShield.setCursor(0,0);
  RGBLCDShield.print("QRE1113 (Analog)");       // Line Sensor Breakout - QRE1113

  iQRE1113Value = analogRead(iQRE1113);
  
  // Set the cursor to column 0, line 1
  RGBLCDShield.setCursor(0, 1); 
  RGBLCDShield.print("iQRE1113 = ");            // iQRE1113
  RGBLCDShield.print( iQRE1113Value );          // iQRE1113Value

}

setup.ino

// Setup
void setup() 
{

  // set up the LCD's number of columns and rows: 
  RGBLCDShield.begin(16, 2);
  RGBLCDShield.setBacklight(GREEN);
  
  // Display
  // Set the cursor to column 0, line 0  
  RGBLCDShield.setCursor(0,0);  
  RGBLCDShield.print("Don Luc");           // Don luc
  // Set the cursor to column 0, line 1
  RGBLCDShield.setCursor(0, 1);
  RGBLCDShield.print("QRE1113 (Analog)");  // Seven-Segment Display
  delay(5000);

  // Clear
  RGBLCDShield.clear();
 
}

Don Luc