SUMMER TRAINING REPORTON

INTERFACING OF A STEPPER MOTOR WITH AN 8051 MICROCONTROLLER

TO

NORTHERN INDIA ENGINEERING COLLEGE, NEW DELHI for the degree

OfBachelor in Technology

In Electronics & Communication

Department of Electronics & Communication Engg.NORTHERN INDIA ENGINEERING COLLEGE,

FC-26, SHASTRI PARK, NEW DELHI-53 MAY 2010

SUBMITTED BY:

YOGENDER KUMAR ARYA – 0931562808 (ECE-S3)

ANUJ SIROHI – 0961562808 (ECE-S3)

AMIT KUMAR - 1071562808(ECE-S3)

CERTIFICATE

This is to certify that Project Report titled “INTERFACING OF A STEPPER MOTOR WITH AN 8051 MICROCONTROLLER”, which is submitted by following students of Bachelors in Technology in Electronics and Communication Engg. Of NORTHERN INDIA ENGINEERING COLLEGE, NEW DELHI, under my supervision.

Projectee:

YOGENDER KUMAR ARYA – 0931562808

ANUJ SIROHI – 0961562808

AMIT KUMAR - 1071562808

Head of the department Supervisor/Guide

ACKNOWLEDGEMENT

We feel highly privileged to express our deep sense of gratitude to all those who helped us during our project work. We would like to express our grateful thanks for the help and advice given to us by ………… , HOD ECE Dept., for their valuable guidance in our project.

We express our gratitude and reverence to the preceptor and project Guide ..……. for his advice, guidance and support which helped us in completing our project.

We are also highly thankful to the management of NORTHERN INDIA ENGINEERING COLLEGE, for providing necessary facilities and infrastructure.

Date:

APPROVED BY: HOD……

OVERVIEW

In our project we have explained how to control and run a stepper motor through microcontroller interfacing. The circuit incorporates a small high quality stepper motor combined with a series of driver IC to enable P89V51RD2FN microcontroller in controlling of the stepper motor.

PART 1INTRODUCTION

INDEXER DRIVER MOTOR

STEP PULSES MOTOR CURRENT

Stepper motors are used in a variety of applications, including high and low propulsion technology, computer peripherals, machine tools, robotics, etc. The interest in this system has been steadily increasing requirements for accuracy and repeatability while at the same time placing ever tighter demands on the maximum and constancy of speed as well as position resolution. However it has a non-linear and coupled dynamic structure so we could use different control schemes to make the stepper more competitive to use in different levels of application.

Motion Control means to accurately control the movement of an object based on speed, distance, load, inertia, direction or a combination of all these factors. There are numerous types of motion control systems, including; Stepper Motor, Linear Step Motor, DC Brush, Brushless, Servo, Brushless Servo and more. This document concentrates upon Step Motor technology.

In Theory, a Stepper motor is a marvel in simplicity. It has no brushes, or contacts. Basically it's a synchronous motor with the magnetic field electronically switched to rotate the armature magnet around.

A Stepping Motor System consists of three basic elements, often combined with some type of user interface (Host Computer):

FIG-1: BLOCK DIAGRAM OF STEPPING MOTOR SYSTEMFIG-1: BLOCK DIAGRAM OF STEPPING MOTOR SYSTEM

The Indexer is a micro-controller capable of generating step pulses and direction signals for the driver. In addition, the indexer is typically required to perform many other sophisticated command functions.

The Driver (or Amplifier) converts the indexer command signals into the power necessary to energize the motor windings. There are numerous types of drivers, with different current/amperage ratings and construction technology. Not all drivers are suitable to run all motors, so when designing a Motion Control System the driver selection process is critical.

The Step Motor is an electromagnetic device that converts digital pulses into mechanical shaft rotation.

Advantages of step motors are low cost, high reliability, high torque at low speeds and a simple, rugged construction that operates in almost any environment. The main disadvantages in using a step motor is the resonance effect often exhibited at low speeds and decreasing torque with increasing speed.

IMPORTANCE

The importances of this design over the conventional designs are summarized below:

• To provide remote & easy access to a system.• It is less time consuming, easy to control. • Controlling can be done easily by just using keyboard.• Comparatively low cost.• Low maintenance required.• Remarkable accuracy can be achieved.• High Reliability.• Low capacity motors can be used. • Low-power position control applications.

REQUIREMENTS

Unipolar stepper motor P89V51RD2FN Microcontroller L293D Driver IC Computer Interfacing

PART 2STEPPER MOTOR

2.1 INTRODUCTION: A stepper motor is a brushless, synchronous electric motor that can divide a full rotation into a large number of steps. The motor's position can be controlled precisely, without any feedback mechanism (open loop control). Most electric motors are controlled by a simple on/off, and the reverse circuitry. On some there is an attempt to roughly control rotational speed. But a handful of motors use sophisticated control electronics to

enable precise control of rotation, not just of speed but of actual rotational position. First is the computer controlled stepper motor, and the second is the computer controlled servo motor. These two systems are capable of accurate rotational positioning to within a few degrees; both are used with small motors that can act low power actuators. The difference between the two is a question of whether the control loop that determines the positioning is open or closed. The stepper motor uses an open loop with no feedback, position being determined by a software counter in the controlling computer. Stepper motors translate digital switching signals into motion. They are in consequences widely used in motion, automated machine tools, disk drives, and a variety of other applications requiring precise motion under computer control.

A stepper motor has the following performance characteristics:

1. Rotation in both directions, 2. Precision angular incremental changes,

3. Repetition of accurate motion,

4. A holding torque at zero speed,

5. Capability for digital control. A stepper motor can move in accurate angular increments know as steps in response to the application of digital pulses to an electric drive circuit from a digital controller. The number and rate of the pulses control the position and speed of the motor shaft. Generally, stepper motors are manufactured with steps per revolution of 12, 24, 72, 144, 180, and 200, resulting in shaft increments of 30, 15, 5, 2.5, 2, and 1.8 degrees per step. Steppers require that their power source be continuously pumped in specific patterns. These patterns or step sequences, determine the speed and direction of a stepper’s motion. For each pulse or step input, the stepper motor rotates a fixed angular increment; typically 1.8 or 7.5 degrees. The fixed stepping angle gives steppers their precision. As long as the motors maximum limits of speed or torque are not exceeded, the controlling program knows a steppers precise position at any given time. Steppers are driven by the interaction (attraction and repulsion) of magnetic fields. The driving magnetic field rotates. As strategically coils are switched on and off. This pushes and pulls the permanent magnets arranged

STATOR

ROTOR

TEETH

around the edge of a rotor that drives the output shaft. When the on off pattern of the magnetic fields is in the proper sequence, the stepper turns (when its not, the stepper sits and quivers). During start, higher than normal current can be expected to be drawn. This momentary current rise is a function of the static friction within the motor and associated machine as well as any load the machine may be under at the time of startup. If starting current exceeds acceptable values, the motor is disconnected from the supply voltage to prevent damage to both the motor and drive devices. Control of this parameter is usually not seen in small motor applications, but can be significant on larger machines. In many applications, it is unsafe or undesirable to allow a motor to coast to a stop. Dynamic braking can be used to eliminate this problem. In dynamic braking, the motor is loaded with an external resistor after electric power has been removed. This external resistance dissipates the mechanical energy of the motor to bring it to a quicker slowdown. Dynamic braking is most effective when motor speeds are high. Regenerative braking is an alternate form of dynamic braking. In regenerative braking, mechanical energy is converted back to electrical energy and returned to the energy source instead of being dissipated. Regenerative braking is effective to speeds of zero. Reversing motor rotational direction may be desirable in many applications. Depending on the type of motor, reversing rotational direction is easily accomplished. Exchanging power leads in an AC machine, reversing power polarity of a DC machine, or reversing input pulse sequences for a stepper motor will accomplish rotational reversal. In the first two cases, reversal can be implemented through an extra set of contacts in the controller while stepper reversal is software based. In many applications, this is incorporated within the dynamic braking system. Velocity control is depended on the type of motor being used. The velocity of DC motors can be controlled by varying the voltage at the terminals of the motor. Synchronous AC machines respond to changes in frequency of the power supply. Stepper motor velocity is controlled in the frequency of the input pulses. There are two methods to implement speed control, open and closed loop. In closed loop, information about motor speed is machines respond to changes in frequency of the power supply. Stepper motor velocity is controlled in the frequency of the input pulses. There are two methods to implement speed control, open and closed loop. In closed loop, information about motor speed is feed into the control circuit which makes appropriate changes to regulate motor speed. Open loop control does not feed any information from motor to controller. Open loop control is most often seen in stepper motors.

The motor’s speed depends upon how fast the controller runs through the step sequence. At any time the controller can stop in the mid sequence. If it leaves power to any of the energized coils on, the motor is locked in the place by their magnetic fields. This point’s out another stepper motor benefit: built-in-brakes. To effectively drive a machine, all of the functions distinguished above may need to be applied to each motor on a given machine. Not only do each motor need to be controlled, but also the relationship between motors. As such, control systems may quickly grow in size and complexity.

2.2 Common Characteristics of Stepper Motors: Stepper motors are not just rated by voltage. The following elements characterize a given stepper motor:

Voltage: Stepper motors usually have a voltage rating. This is either printed directly on the unit, or is specified in the motor's datasheet. Exceeding the rated voltage is sometimes necessary to obtain the desired torque from a given motor, but doing so may produce excessive heat and/or shorten the life of the motor. Resistance: Resistance-per-winding is another characteristic of a stepper motor. This resistance will determine current draw of the motor, as well as affect the motor's torque curve and maximum operating speed.

Degrees per step: This is often the most important factor in choosing a stepper motor for a given application. This factor specifies the number of degrees the shaft will rotate for each full step. Half step operation of the motor will double the number of steps/revolution, and cut the degrees-per-step in half. For unmarked motors, it is often possible to carefully count, by hand, the number of steps per revolution of the motor. The degrees per step can be calculated by dividing 360 by the number of steps in 1 complete revolution Common degree/step numbers include: 0.72, 1.8, 3.6, 7.5, 15, and even 90. Degrees per step are often referred to as the resolution of the motor. As in the case of an unmarked motor, if a motor has only the number of

steps/revolution printed on it, dividing 360 by this number will yield the degree/step value.

2.3 Types of Stepper Motors:

There are basically three types of stepping motors:1) Variable reluctance type stepper motor2) Permanent magnet type stepper motor 3) Hybrid type stepper motorThey differ in terms of construction based on the use of permanent magnets and/or iron rotors with laminated steel stators.

VARIABLE RELUCTANCE: The variable reluctance motor does not use a permanent magnet. This type of construction is good in non industrial applications that do not require a high degree of motor torque.

The variable reluctance motor in the above illustration has four "stator pole sets" (A, B, C,), set 15 degrees apart. Current applied to pole A through the motor winding causes a magnetic attraction that aligns the rotor (tooth) to pole A. Energizing stator pole B causes the rotor to rotate 15 degrees in alignment with pole B. This process will continue with pole C and back to A in a clockwise direction.Reversing the procedure (C to A) would result in a counterclockwise rotation.

PERMANENT MAGNET:The permanent magnet motor, also referred to as a "canstack" motor, has, as the name implies, a permanent magnet rotor. It is a relatively low speed, low torque device with large step angles of either 45 or 90 degrees. It's simple construction and low cost make it an ideal choice for non industrial applications.

Unlike the other stepping motors, the PM motor rotor has no teeth and is designed to be magnetized at a right angle to its axis. The above illustration shows a simple, 90 degree PM motor with four phases (A-D). Applying current to each phase in sequence will cause the rotor to rotate by adjusting to the changing magnetic fields. Although it operates at fairly low speed the PM motor has a relatively high torque characteristic. It has a 90degree /pulse step angle.

HYBRID:Hybrid motors combine the best characteristics of the variable reluctance and permanent magnet motors.They are constructed with multi-toothed stator poles and a permanent magnet rotor. Standard hybrid motors have 200 rotor teeth and rotate at 1.80 step angles. Other hybrid motors are available in 0.9º and 3.6º step angle configurations. Because they exhibit high static and dynamic torque and run at very high step rates, hybrid motors are used in a wide variety of industrial applications.

The type of motor determines the type of drivers, and the type of translator used. Of the permanent magnet stepper motors, there are several "sub flavors" available.

These include the Unipolar and Bipolar.

Unipolar Stepper Motors : Unipolar motors are relatively easy to control. A simple 1-of-'n' counter circuit can generate the proper stepping sequence, and drivers as simple as 1 transistor per winding are possible with unipolar motors. Unipolar stepper motors are characterized by their center-tapped windings. A common wiring scheme is to take all the taps of the center-tapped windings and feed them +MV (Motor voltage). The driver circuit would then ground each winding to energize it.

In this project we use unipolar stepper motor which has five or six wires and four coils (actually two coils divided by center connections on each coil). The center connections of the coils are tied together and used as the power connection. They are called unipolar steppers because power always comes in on this one pole.

Bipolar Stepper Motors : Unlike unipolar stepper motors, bipolar units require more complex driver circuitry. Bipolar motors are known for their excellent size/torque ratio, and provide more torque for their size than unipolar motors.

Bipolar motors are designed with separate coils that need to be driven in either direction (the polarity needs to be reversed during operation) for proper stepping to occur. This presents a driver challenge. Bipolar stepper motors use the same binary drive pattern as a unipolar motor, only the '0' and '1' signals correspond to the polarity of the voltage applied to the coils, not simply 'on-off' signals. Figure 5.1 shows a basic 4-phase bipolar motor's coil setup and drive sequence.

Variable Reluctance Stepper Motors: Sometimes referred to as Hybrid motors, variable reluctance stepper motors are the simplest to control over other types of stepper motors. Their drive sequence is simply to energize each of the windings in order, one after the other (see drive pattern table below) This type of stepper motor will often have only one lead, which is the common lead for all the other leads. This type of motor feels like a DC motor when the shaft is spun by hand; it turns freely and you cannot feel the steps. This type of stepper motor is not permanently magnetized like it’s unipolar and bipolar counterparts.

2.4 How Stepper Motors Work: Operation principle of a stepper motor is when we energize a coil of stepper motor, the shaft of stepper motor (which is actually a permanent magnet) align itself according to poles of energized coil. So when motor coils are energized in a particular sequence, motor shaft tend to align itself according to pole of coils and hence rotates.

Stepper motors, however, behave differently than standard DC motors. First of all, they cannot run freely by themselves. Stepper motors do as their name suggests -- they "step" a little bit at a time. Stepper motors also differ from DC motors in their torque-speed relationship. DC motors generally are not very good at producing high torque at low speeds, without the aid of a gearing mechanism. Stepper motors, on the other hand, work in the opposite manner. They produce the highest torque at low speeds. Stepper motors also have another characteristic, holding torque, which is not present in DC motors.

Holding torque allows a stepper motor to hold its position firmly when not turning. This can be useful for applications where the motor may be starting and stopping, while the force acting against the motor remains present. This eliminates the need for a mechanical brake mechanism. Steppers don't simply respond to a clock signal, they have several windings which need to be energized in the correct sequence before the motor's shaft will rotate. Reversing the order of the sequence will cause the motor to rotate the other way. If the control signals are not sent in the correct order, the motor will not turn properly. It may simply buzz and not move, or it may actually turn, but in a rough or jerky manner. A circuit which is responsible for converting step and direction signals into winding energization patterns is called a translator. Most stepper motor control systems include a driver in addition to the translator, to handle the current drawn by the motor's windings.

2.5 STEP MODES:

Stepper motor "step modes" include Full, Half and Micro step. The type of step mode output of any motor is dependent on the design of the driver.

FULL STEP: Standard (hybrid) stepping motors have 200 rotor teeth, or 200 full steps per revolution of the motor shaft. Dividing the 200 steps into the 360º's rotation equals a 1.8º full step angle. Normally, full step mode is achieved

by energizing both windings while reversing the current alternately. Essentially one digital input from the driver is equivalent to one step.

HALF STEP: Half step simply means that the motor is rotating at 400 steps per revolution. In this mode, one winding is energized and then two windings are energized alternately, causing the rotor to rotate at half the distance, or 0.9º's. (The same effect can be achieved by operating in full step mode with a 400 step per revolution motor). Half stepping is a more practical solution however, in industrial applications. Although it provides slightly less torque, half step mode reduces the amount "jumpiness" inherent in running in a full step mode.

MICROSTEP: Micro stepping is a relatively new stepper motor technology that controls the current in the motor winding to a degree that further subdivides the number of positions between poles. AMS micro steppers are capable of rotating at 1/256 of a step (per step), or over 50,000 steps per revolution.

Micro stepping is typically used in applications that require accurate positioning and a fine resolution over a wide range of speeds.MAX-2000 micro steppers integrate state-of-the-art hardware with "VRMC" (Variable Resolution Micro step Control) technology developed by AMS. At slow shaft speeds, VRMCs produces high resolution micro step positioning for silent, resonance-free operation. As shaft speed increases, the output step resolution is expanded using "on-motor-pole" synchronization. At the completion of a coarse index, the target micro position is trimmed to 1/100 of a (command) step to achieve and maintain precise positioning.

2.6 ADVANTAGES:

Stepper motors have several advantages:

a) They can be operated in open loop systemsb) Position error is that of a single step.c) Error is non-cumulative between stepsd) Discrete pulses control motor positione) Interface well to digital and microcontroller systemsf) Mechanically simple, no brushes, highly reliableg) Step motors are low cost, high reliability, high torque at low speeds and a simple, rugged construction that operates in almost any environment.

2.7 DISADVANTAGES:

Disadvantages are:a) Fixed increments of motionb) Low efficiency, driver choice importantc) High oscillation and overshoot to a step inputd) Limited power outpute) Limited ability to handle large inertial loadsf) Friction errors can increase position errorg) Step motor is the resonance effect often exhibited at low speeds and decreasing torque with increasing speed.

PART 3MICROCONTROLLER

3.1 INTRODUCTION:

Microcontrollers are "special purpose computers." Microcontrollers do one thing well. There are a number of other common characteristics that define microcontrollers. If a computer matches a majority of these characteristics, then you can call it a "microcontroller": Microcontrollers are "embedded" inside some other device (often a consumer product) so that they can control the features or actions of the

product. Another name for a microcontroller, therefore, is "embedded controller." Microcontrollers are dedicated to one task and run one specific program. The program is stored in (read-only memory) and generally does not change. Microcontrollers are often low-power devices. A desktop computer is almost always plugged into a wall socket and might consume 50 watts of electricity. A battery-operated microcontroller might consume 50 milliwatts. A microcontroller has a dedicated input device and often (but not always) has a small LED or LCD display for output. A microcontroller also takes input from the device it is controlling and controls the device by sending signals to different components in the device. In our project we are using P89C51RD2 MICROCONTROLLER.

3.2 P89V51RD2FN MICROCONTROLLER

The P89C51RD2 is a low-power, high-performance CMOS 8-bit microcontroller with 8K bytes of Flash programmable and erasable read only memory (PEROM). The device is manufactured using Philips’ high-density nonvolatile memory technology and is compatible with the industry-standard MCS-51 instruction set and pinout. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile memory programmer. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Philips P89V51RD2FN is a powerful microcomputer which provides a highly-flexible and cost-effective solution to many embedded control applications.

The P89V51RD2FN provides the following standard features: 8 kB flash microcontroller with 256 byte RAM; Clock type: 12-clk (6-clk opt.) ; External interrupt: 2; I/O pins: 32 ; Memory type: FLASH ; Number of pins: 40 ; Operating frequency: 0~20/40 (6clk/12clk) MHz; Operating

temperature: -40~85 Cel; Power supply: 4.5~5.5V ; Program security: yes; Serial interface: UART ; Series: 80C51 family

3.3 PIN DIAGRAM

3.4 PIN DESCRIPTION

VCC:Supply voltage.

GND:Ground.

Port 0:Port 0 is an 8-bit open-drain bi-directional I/O port. As an output port, each pin can sink eight TTL inputs. When 1s are written to port 0 pins, the pins can be used as high impedance inputs.Port 0 may also be configured to be the multiplexed low order address/data bus during accesses to external program and data memory. In this mode P0 has internal pull ups.Port 0 also receives the code bytes during Flash programming, and outputs the code bytes during program verification. External pull ups are required during program verification.

Port 1:Port 1 is an 8-bit bi-directional I/O port with internal pull-ups. The Port 1 pins are pulled high by the internal pull-ups when ‘1’s are written to them and can be used as inputs in this state. As inputs, Port 1 pins that are externally pulled LOW will source current (IIL) because of the internal pull-ups. P1.5, P1.6, P1.7 have high current drive of 16 mA. Port 1 also receives the low-order address bytes during the external host mode programming and verification.

Port 2:Port 2 is an 8-bit bi-directional I/O port with internal pull ups. The Port 2 output buffers can sink/source four TTL inputs. When 1s are written to Port 2 pins they are pulled high by the internal pull ups and can be used as inputs. As inputs, Port 2 pins that are externally being pulled low will source current (IIL) because of the internal pull ups. Port 2 emits the high-order address byte during fetches from external program memory and during accesses to external data memory that use 16-bit addresses. In this application, it uses strong internal pull ups when emitting 1s. During accesses to external data memory that use 8-bit addresses (MOVX @ RI), Port 2 emits the contents of the P2 Special Function Register. Port 2 also receives the high-order address bits and some control signals during Flash programming and verification.

Port 3:Port 3 is an 8-bit bi-directional I/O port with internal pull ups. The Port 3 output buffers can sink/source four TTL inputs. When 1s are written to Port 3 pins they are pulled high by the internal pull ups and can be used as inputs. As inputs, Port 3 pins that are externally being pulled low will source current

(IIL) because of the pull ups. Port 3 also serves the functions of various special features of the AT89C51 as listed below:

Port 3 also receives some control signals for Flash programming and verification.

RST:Reset input. A high on this pin for two machine cycles while the oscillator is running resets the device.

ALE/PROG:Address Latch Enable output pulse for latching the low byte of the address during accesses to external memory. This pin is also the program pulse input (PROG) during Flash programming. In normal operation ALE is emitted at a constant rate of 1/6 the oscillator frequency, and may be used for external timing or clocking purposes. Note, however, that one ALE pulse is skipped during each access to external Data Memory.If desired, ALE operation can be disabled by setting bit 0 of SFR location 8EH. With the bit set, ALE is active only during a MOVX or MOVC instruction. Otherwise, the pin is weakly pulled high. Setting the ALE-disable bit has no effect if the microcontroller is in external execution mode.

PSEN:Program Store Enable is the read strobe to external program memory. When the microcontroller is executing code from external program memory, PSEN is activated twice each machine cycle, except that two PSEN activations are skipped during each access to external data memory.EA/VPP:

External Access Enable. EA must be strapped to GND in order to enable the device to fetch code from external program memory locations starting at 0000H up to FFFFH. Note, however, that if lock bit 1 is programmed, EA will be internally latched on reset.EA should be strapped to VCC for internal program executions. This pin also receives the 12-volt programming enable voltage(VPP) during Flash programming, for parts that require12-volt VPP.

XTAL1:Input to the inverting oscillator amplifier and input to the internal clock operating circuit.

XTAL2:Output from the inverting oscillator amplifier.

PART 4L293D DRIVER IC

4.1 INTRODUCTION:

The Device is a monolithic integrated high voltage, high current four channel driver designed to accept standard DTL or TTL logic levels and drive inductive loads (such as relays solenoides, DC and stepping motors) and switching power transistors. To simplify use as two bridges each pair of channels is equipped with an enable input. A separate supply input is provided for the logic, allowing operation at a lower voltage and internal clamp diodes are included. This device is suitable for use in switching applications at frequencies up to 5 kHz..

L293D is high voltage, high current Quadruple half - H-Bridge driver ic . Each channel rated at 600mAand can withstand peak currents of 1.2A.Flyback diodes are included for inductive load driving and the enable inputs and output are placed side by side to facilitate the use. These versatile devices are useful for driving a wide range of loads including solenoids, relays DC motors, LED displays filament lamps, thermal print heads and high power buffers.The are supplied in 16 pin plastic DIP packages with a copper lead frame to reduce thermal resistance.

4.2 PIN CONNECTION :

4.3 FEATURES:

TTL, DTL, Compatible Inputs Output current to 600 mA Maximum output voltage to 36 V Transient-Protected Outputs Dual In-Line Plastic Package or Small-Outline IC Package

PART 5OVER ALL SYSTEM

5.1 BLOCK DIAGRAM

5.2 HARDWARE

Interfacing

Interfacing is an important task to be accomplished in almost all automation applications. The digital signals are to be generated to make the hardware run as per the instructions of program. In the present application, the programming is done in .C. programming language. .C. is chosen for its simplicity and ruggedness. It offers simple methods to interact with the serial port through which the interfacing is done. The driver circuit used for the purpose of interfacing consists of Quadruple half - H-bridge L293D driver IC. The signals from the µ-controller are amplified by the L293D which can drive loads up to 600mA. It's input is TTL as well as DTL compatible and the output is up to 36VDC. The stepper motor is driven in full step mode, for every step single windings is energised.

PROGRAMMING

#include <REG2051.H>.#define s0 P1^1#define s1 P1^2#define s2 P1^3

#define s3 P1^4#define en12 P1^0#define en34 P1^6void delay();

void main(){ en12=en34=1;        while(1) { s3=s2=1;

s1=s0=0;                delay();                s3=s0=0;

s2=s1=1; delay();

                s3=s2=0; s1=s0=1;

                delay();                s3=s0=1;

s2=s1=0;                delay();        }}

void delay(){        unsigned int i;        for(i=0;i<3000;i++);}

CONCLUSION

The project was successfully completed after a lot of efforts and work hours. This project underwent controlling of stepper motor, compiling, debugging, removing errors, make it bug free, adding more facilities & interactivity, make it more reliable and user friendly.

Guidance was taken from faculty; help from the friend were accepted at the various project development phases. Many books related to controlling of microcontroller were referred to get the desired results.

REFERENCES

SITES:

http://www.google.com

http://www.wikipedia.com

BOOKS:

The 8051 microcontroller & Embedded system-Muhammad Ali Mazidi

Control System - I.J. Nagrath & kothari

TOOLS AND DEVELOPMENT

Hardware: The hardware used to develop our project includes:

1. Stepper motor.2. L293D Driver IC. 3. A P89V51RD2FN microcontroller.

Software: C language, KEIL Compiler