Difference between revisions of "Lesson 40--Microduino DC Motor Drive (Potentiometer PWM control speed)"

Objective

This tutorial will teach you how to control the speed of a DB motor via the potentiometer.

Equipment

• Microduino-Core
• Microduino-FT232R
• Other equipment
  • Breadboard Jumper one box
  • Breadboard one piece
  • DC motor one
  • Potentiometer one
  • NPN transistor one
  • 2.2k resistor one
  • Diode one
  • USB cable one

Schematic

Description:

When connect the NPN transistor, Base (B) connects with 2.2K resistor, emitter (E) connects the GND and collector (C) connects to motor. As follows:

Program

int potPin = A0; //Potentiometer input pin
int motorPin = 9;//Motor pin
int potValue = 0;//Define the value of potentiometer
int motorValue = 0;//Define the value of motor
void setup() {
 Serial.begin(9600);
}
void loop() {
 potValue = analogRead(potPin);  //Read the value of potentiometer
 motorValue = map(potValue, 0, 1023, 0, 255);//Map to a value among 0~255
 analogWrite(motorPin, motorValue);//Output PWM to motor
 //Display
 Serial.print("potentiometer = " );     
 Serial.print(potValue);
 Serial.print("\t motor = ");
 Serial.println(motorValue);
 delay(2);    
}

Debug

Step 1: Copy the code to IDE and compile it

Step 2: Set up circuit, as follows:

Step 3: Run program

Step 4: Adjust potentiometer, and check the speed of the motor

Result

Twist potentiometer to adjust the motor's speed

Video