Interfacing of dc motor with 8051 micro controller. How the dc motor is interfacing with microcontroller by using L293D driver IC

1. PRESENTED BY,
MANIKANDAN K
18EIR041
MPMC LABOURATORY
09.12.2020
INTERFACING OF DC MOTOR

2. INTERFACING OF DC MOTOR
AIM:
To develop Embedded C programming to interface 8051 microcontroller with DC motor
APPARATUS REQUIRED
S.No Item Specification Quantity
1 Microcontroller 8051 1
2 L293D motor driver - 1
3 DC Motor 12V 1
4 Oscillator crystal 12MHz 1
5 Power supply 5V 1
6 Capacitors 33pF, 10μF 2,1
7 Resistor 330kΩ 2
8 Software: Keil μ Vision 5 - -
9 Software: Proteus 8 - -

3. DC MOTOR
• A motor translates electrical pulses into
mechanical motion
• DC motor works on DC power
Magnitude F=B*l*v
• It follows Lorentz law and Faradays law of
electromagnetic induction principle
• Typical Operating voltages are 6V, 12V or 24V
• DC motors are bidirectional. We can control DC
motor diection by using H-Bridge concept
Principle: “When a current carrying conductor is placed in a
magnetic and electric field, the conductor experiences force”
and the force is the Lorentz force.

4. H-BRIDGE CONFIGURATION :
High Left High Right Low Left Low Right Description
ON OFF OFF ON Motor runs clockwise
OFF ON ON OFF0 Motor runs anti-clockwise
ON ON OFF OFF Motor stops
OFF OFF ON ON Motor stops
TRUTH TABLE OF
H-BRIDGE
CONFIGURATION

5. NEED OF DRIVER CIRCUITRY
 The power requirements of most of DC motor is higher
 Back emf produced by the motor may damage the microcontroller
 L293D is a motor driver IC. Supply voltage between 4.5 to 36V with maximum current
of 600mA
 16 pin H-Bridge driver IC
 Can drive two DC motors
 IN1,IN2- Control signals for M1, OUT1,OUT2-M1 connected
 EN1- enables M1
 IN3,IN4- Control signals for M2, OUT3,OUT4-M2 connected
 EN2- enables M2
 VSS- Supply of IC
 VS- Supply of motor
L293D PIN CONFIGURE

6. CIRCUIT DIAGRAM:

7. EMBEDDED C CODE:
#include<reg52.h>
#include<stdio.h>
void delay(void);
sbit motor_pin_1 = P2^0;
sbit motor_pin_2 = P2^1;
void main()
{
do
{
motor_pin_1 = 1;
motor_pin_2 = 0; //Rotates Motor Anti Clockwise
delay();
motor_pin_1 = 1;
motor_pin_2 = 1; //Stops Motor
delay();
motor_pin_1 = 0;
motor_pin_2 = 1; //Rotates Motor Clockwise
delay();
motor_pin_1 = 0;
motor_pin_2 = 0; //Stops Motor
delay();
}while(1);
}
void delay()
{
int i,j;
for(i=0;i<1000;i++)
{
for(j=0;j<1000;j++)
{
}
}
}

8. PROCEDURE

9. RESULT
Thus, Embedded C programming to interface 8051 microcontroller with
DC motor was developed and output was verified successfully