UP AND DOWN CONTROLLED SPEED OF DC MOTOR IN EMBEDDED SYSTEM

1. UP AND DOWN CONTROLLED SPEED OF DC MOTOR IN EMBEDDED SYSTEM SUBMITTED BY EDGEFX TEAM

2. ABSTRACT • The speed of motor is directly proportional to the DC voltage applied across its terminals. • PWM (Pulse Width Modulation) wave can be used to control the speed of the motor • the average voltage given or the average current flowing through the motor will change depending on the ON and OFF time of the pulses • The duty cycle of the wave controls its speed . On changing the duty cycle (ON time), we can change the speed

3. BLOCK DIAGRAM

4. HARD WARE EQUIPMENTS • POWER SUPPLY • MICROCONTROLLER (AT89S52/AT89C51) • MOTOR DRIVER • DC MOTOR • PWM • PUSH BUTTONS • LCD • 1N4007 • LED • RESISTORS & CAPACITORS

6. EMBEDDED SYSTEMS Definition for :- EMBEDDED SYSTEMS • A combination of hardware and software which together form a component of a larger machine. • An example of an embedded system is a microprocessor that controls an automobile engine. • An embedded system is designed to run on its own without human intervention, and may be required to respond to events in real time.

7. EMBEDDED SYSTEMS

8. MICRO CONTROLLER AT89S52 • Compatible with MCS®-51 Products • 8K Bytes of In-System Programmable (ISP) Flash Memory • 4.0V to 5.5V Operating Range • Crystal Frequency 11.0592MHZ • Three-level Program Memory Lock • 256 x 8-bit Internal RAM • 32 Programmable I/O Lines • Three 16-bit Timer/Counters • Eight Interrupt Sources • Full Duplex UART Serial Channel • Watchdog Timer

9. PIN DIAGRAM OF AT89S52

10. PWM • The PWM switching frequency has to be much faster than what would affect the load, which is to say the device that uses the power. • The term duty cycle describes the proportion of on time to the regular interval or period of time; • a low duty cycle corresponds to low power, because the power is off for most of the time. Duty cycle is expressed in percent, 100% being fully on.

11. PWM APPLICATIONS • Telecommunications • Power delivery • Voltage regulation • Audio effects and amplification.

12. LED LEDs are semiconductor devices are made out of silicon When current passes through the LED, it emits photons as a byproduct. Normal light bulbs produce light by heating a metal filament until its white hot LEDs present many advantages over traditional light sources including lower energy consumption, longer lifetime, improved robustness, smaller size and faster switching

13. DC- MOTOR • A DC motor is an electric motor that runs on direct current (DC) electricity. In any electric motor, operation is based on simple electromagnetism. • A simple 2-pole DC electric motor (here red represents a magnet or winding with a "North" polarization, while green represents a magnet or winding with a "South" polarization). • Every DC motor has six basic parts -- axle, rotor (a.k.a., armature), stator, commutator, field magnet(s), and brushes.

14. MOTOR DRIVER (L293D) • Features: • Wide supply-voltage range: 4.5V to 36V • Separate input- logic supply • Internal ESD protection • Thermal shutdown • High-Noise-Immunity input • Functional Replacements for SGS L293 and SGS L293D • Output current 1A per channel (600 mA for L293D) • Peak output current 2 A per channel (1.2 A for L293D) • Output clamp diodes for Inductive Transient suppression(L293D)

15. DESCRIPTION • L293D is a dual H-bridge motor driver integrated circuit (IC). • In its common mode of operation, two DC motors can be driven simultaneously, both in forward and reverse direction. • The motor operations of two motors can be controlled by input logic at pins 2 & 7 and 10 & 15. • Input logic 00 or 11 will stop the corresponding motor. Logic 01 and 10 will rotate it in clockwise and anticlockwise directions, respectively. • Enable pins 1 and 9 (corresponding to the two motors) must be high for motors to start operating. When an enable input is high, the associated driver gets enabled

16. LIQUID CRYSTAL DISPLAY (LCD) • Most common LCDs connected to the microcontrollers are 16x2 and • 20x2 displays. • This means 16 characters per line by 2 lines and 20 characters per line • by 2 lines, respectively. • The standard is referred to as HD44780U, which refers to the controller • chip which receives data from an external source (and communicates • directly with the LCD.

17. LCD BACKGROUND • If an 8-bit data bus is used the LCD will require 11 data lines • (3 control lines plus the 8 lines for the data bus) • The three control lines are referred to as EN, RS, and RW • EN=Enable (used to tell the LCD that you are sending it data) • RS=Register Select (When RS is low (0), data is treated as a command) • (When RS is High(1), data being sent is text data ) • R/W=Read/Write (When RW is low (0), the data written to the LCD) • (When RW is low (0), the data reading to the LCD)

18. BIBILOGRAPHY • The 8051 Microcontroller and Embedded systems” by Muhammad Ali Mazidi and Janice Gillispie Mazidi , Pearson Education. • ATMEL 89S52 Data Sheets. • www.atmel.com • www.beyondlogic.org • www.wikipedia.org • www.howstuffworks.com • www.alldatasheets.com

19. THANK ‘Q’