PWM Motor Drive

CODE FOR PWM DRIVE

int motor = 9;
int speed = 0;

void setup() {
  pinMode(motor, OUTPUT);
}

void loop() {
  analogWrite(motor, speed);

  speed = speed + 31;
 
  if (speed > 250)
  {
    speed = 255;
  }

  delay(4000);
 
  if (speed > 250)
  {
    speed = 0;
  }

}

Seven Segment Display Numbers

Code for driving segment display. To drive a common cathode the NOT operator ! must be removed from the front of the array in the highlighted part of the code.

// make an array to save Sev Seg pin configuration of numbers

int num_array[10][7] = {  { 1,1,1,1,1,1,0 },    // 0

                          { 0,1,1,0,0,0,0 },    // 1

                          { 1,1,0,1,1,0,1 },    // 2

                          { 1,1,1,1,0,0,1 },    // 3

                          { 0,1,1,0,0,1,1 },    // 4

                          { 1,0,1,1,0,1,1 },    // 5

                          { 1,0,1,1,1,1,1 },    // 6

                          { 1,1,1,0,0,0,0 },    // 7

                          { 1,1,1,1,1,1,1 },    // 8

                          { 1,1,1,0,0,1,1 }};   // 9

                                      

//function header

void Num_Write(int);

void setup()

{

  // set pin modes

  pinMode(6, OUTPUT);  

  pinMode(7, OUTPUT);

  pinMode(8, OUTPUT);

  pinMode(9, OUTPUT);

  pinMode(10, OUTPUT);

  pinMode(11, OUTPUT);

 pinMode(12, OUTPUT);

 

 }

void loop()

{

  for (int counter = 10; counter > 0; --counter)

  {

   delay(1000);

   Num_Write(counter-1);

  }

  delay(5000);

}

// this functions writes values to the sev seg pins 

void Num_Write(int number)

{

  int pin= 6;

  for (int j=0; j < 7; j++) {

   digitalWrite(pin, !num_array[number][j]); //Inverted array value due to Common Anode display

   pin++;

  }

}

Common Anode Seven-Segment Display Test

// 7 Segment test

void setup()
{
  // define pin modes
 
 pinMode(6,OUTPUT);
 pinMode(7,OUTPUT);
 pinMode(8,OUTPUT);
 pinMode(9,OUTPUT);
 pinMode(10,OUTPUT);
 pinMode(11,OUTPUT);
 pinMode(12,OUTPUT);

}

void loop()
{
 
  for(int i=6;i<13;i++) //Clear LEDs since the outputs start LOW (LED ON)
  {
    digitalWrite(i,HIGH);
    delay(1);
  }
  // loop to turn leds segments ON by sinking them (taking pins to GND)
 
  for(int i=6;i<13;i++)
  {
    digitalWrite(i,LOW);
    delay(600);
  }
 
  // loop to turn leds segnemts OFF by taking the pins to V+
  for(int i=6;i<13;i++)
  {
    digitalWrite(i,HIGH);
    delay(600);
  }
 
 
  delay(1000);

}

PWM Motor Control

PWM Motor Code

This code makes the motor speed up until it reaches the highest speed possible and then it resets to low speed again.

------------------------

int motor = 9;
int speed = 0;

void setup() {
  pinMode(motor, OUTPUT);
}

void loop() {
  analogWrite(motor, speed);

  speed = speed + 31;
  
  if (speed > 250)
  { 
    speed = 255;
  }

  delay(4000);
  
  if (speed > 250)
  { 
    speed = 0;
  }

}

Target Game

Hook up the following circuit starting with the servo first.

int sensorPin = A0;
int ledPin = 13;
int sensorValue;
#include <Servo.h>
Servo myservo;
void setup()
{
  myservo.attach(9);
  pinMode(ledPin, OUTPUT);
  //Serial.begin(9600);
}
void loop()
{
  sensorValue = analogRead(sensorPin);
  //Serial.println(sensorValue); // Print value to monitor
  analogWrite(ledPin, sensorValue);
  if (sensorValue < 100)
  {
  myservo.write(180);              // tell servo to go to position in variable 'pos'
  delay(15);
  }
  else
  {
  myservo.write(90);    
  delay(2000);
  }
}

LED class with blink method

Below is a class I created to blink multiple LEDs at independent blink rates. This code below is the initial test of the class and shows you how to go about building a class of your own but you can save a lot of typing by downloading the library from Github using the following link:

led class code library

Just download led.cpp and led.h and put them in a library folder (call it led) where the Arduino libraries are located.

The code sample program is self explanintory. Just create an LED object using the following:

LED LED1 = LED(3); where 3 is the pin number you want to hook to the LED.

LED1.blink(100); Sets the blink rate of the LED to 100 milliseconds.

LED1.on(); Turns on the LED

LED1.off(); Turns off the LED

LED1.status(); Returns the status of the LED on or off

Have fun.


LED class and test of class ----------------------------------------------------------

class LED
{
public:
LED(int pin);
void on();
void off();
bool status();
void blink(int delayTime);

private:
int _pin;
bool _status;
int _delayTime;
int _rate;
unsigned long previousMillis = millis();
};


LED::LED(int pin)
{
  _pin = pin;
  pinMode(_pin,OUTPUT);
}

 void LED::on()
{
  digitalWrite(_pin, HIGH);
_status = 1;
}

 void LED::off()
{
  digitalWrite(_pin, LOW);
 _status = 0;}

 bool LED::status()
{
  return _status;
}

 void LED::blink(int delayTime)
{
  _delayTime = delayTime;

  if (millis() - previousMillis >= _delayTime) //if current system time - last time is greater then desired delay then make last system
  // equal to current system time
  {
    previousMillis = millis();

    if (_status == 0)
    {
      on();
    }
    else
    {
      off();
    }

  }
 }

//Test of class --------------------

LED LED1 = LED(3);
LED LED2 = LED(4);
LED LED3 = LED(2);


void setup()
{

}

void loop()
{
LED1.blink(100);
LED2.blink(1000);
LED3.blink(500);
}

Ultrasonic Sensor

Moving Dot Ultrasonic Sensor

This circuit lights up dots successively as objects move further away from the ultrasonic sensor.

Modify the sensitivity and increments by changing the numbers in the "if" statement.

The 5 LED in the circuit can be used to indicate the values from a wide variety of sensors.