Final Report on Cut to length controller using P89LPC932

. Cut to Length Controller

___________________________________________________________________________________________ V.T Patel Department Of Electronics & Communication Engineering 1

Scenario and Progress of Industry

Automation

Overview of the System

Operation Overview and Problem

Definitions

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1.1

The foundations of the industrial automation need to be traced to the

development of quantum mechanics, classical mechanics, electronics and the

essential one, process theory, which describes the behavior of output variables as

a function of adjustable and non adjustable variables and time. Also the inventions

such as the vacuum tube , the transistor, the integrated circuit and the

microprocessor, which led to the emergence of the microelectronics, and a wide

variety of new sensing devices are essential to the revolution of the industrial

automation. Process control theory has provided knowledge on the principles of

control, on the ways of implementing these principles, and on the mathematical

SCENARIO & PROGRESS OF INDUSTRIAL AUTOMATION

During the eighties emerged a profuse literature pointing at a number of

potential advantages of recent microelectronics-based industrial automation for

developing countries. It is claimed that industrial automation is leading to

fundamental changes in production organizations , optimal scales of output and

economic scope , vertical integration and the relationship between large and small

firms that would generally be favorable to any country.

A new phase in the replacement of human effort by machines began to

emerge around the early twentieth century with the development of industrial

automation. Unlike mechanization industrial automation not only involves the

replacement of physical effort by machines but entails the displacement of some

of the decision making capabilities of the operator. It is based on the concept of

feedback control which consists of a procedure of measuring and inspecting or

‘sensing’ the evaluation and processing of this information in relation to theory or

algorithm of the process, and an output of instructions as a response if required.

Feed back control allows for the development of more flexible machines and

production processes.



models to represent processes. Microelectronics, i.e. electronic using very small

solid state components, provided devices for storing, processing and computing

information that are notably smaller and diminishing in size, of an exceedingly

high and increasing speed and reliability, and , of very low and decreasing costs.

The introduction of digital computers in the 1960s offered the possibility

of breaking away from previous unreliable electromechanical controls and move

into faster, reliable and more accurate devices, capable of data storing and

processing and of performing a series of complex mathematical operations. But ,

by and large, early computers were a failure because of constant breakdowns due

to their sensitivity to the external environment leading to expensive back-up

measures and difficulties in developing models and writing programs that took all

intervening variables into account. This situation changed drastically the advent of

microelectronics. Since 1975, devices such as programmable logic controllers,

micro and process computers have been developed. Together with appropriate

software and novel measuring instrumentation, also microelectronics based , the

new control devices are simultaneously capable of data gathering, processing and

storing, computing ,regulating controlling, interfacing with the operator and

communicating with other devices and outside the system with or without human

intervention.

Because of the emphasis on advance and high tech equipments with

feedback control as the defining factor, industrial automation includes a wide

variety of self-regulating equipment which is in almost any industry, It also

includes any combination of machines which are jointly controlled from a

computer. And, it possibly consists of parts of plants or even whole factories

which are completely unmanned and computer controlled, although ‘factories of

the future’ still seem to be a long way away.

The diffusion of industrial automation since the advent of microelectronics

has proceeded at a very fast rate. In continuous process industries more powerful



and sophisticated process control units and sensors were developed ,while in

batch industries, particularly in mechanical engineering , new process equipment

such as numerically and computer controlled machine tools, computer-aided

design and flexible manufacturing systems emerged.

1.2

Automatic continuous cutting along a straight line required the combined

accurate positioning of the tool and work piece along a length. This involves a

complex set of movements the commands for which, it is believed at the real time,

can be conveyed to the motor of the machines tool through a device or

‘servomechanism’ which has created digital signals corresponding to numbers.

These signals were then compared with signals arising from the actual position of

the tool and work piece prompting corrective action if necessary.

Perhaps the best way to start with is the analysis of the system objectives. In

as much as automated equipment requires automatic control, data on the use of

industrial control and instrumentation, should provide an idea of the real time

implementation.

Here first we are going to see the purpose of the system and then we come

to know how we have derived the system objectives along with the application

background.

1.2.1 Purpose of the system :

The purpose of designing such system is to provide a cost effective and precise

control over a servo drive for a dedicated application and enhanced functionality

of servo drive MP-controller.

OVERVIEW OF THE SYSTEM (C2L)



( Here dedicated application is in terms of controlling servo device in such way,

that the servo motor connected, rotates for a derived number of pulses and gives

the exact desired length of the sheet without any damage. )

1.2.2 Objectives of the system :

The system have the following objectives such that it is reliable enough to apply

for an industrial application.

The objectives are :

1) The system must have the basic functionality of servo drive controlling MP,

such that system can completely replace the MP unit.

2) The system must be able to provide pulse train in frequency range of 1 to 70

KHz for the pulse potion mode of the servo drive.

3) The system must be able to sense the mechanical assembly failure such that it

will resume the functionality with the previous parameters fed.

4) The mechanical assembly should be controlled such a way that desired length

of the sheet can be achieved without any damage and the length must be in

mm.

5) The system must be able to communicate human interfaces like LCD or HMI.

6) The system should be very cost effective and highly efficient.

7) The parameters listed below can be easily inserted through any media to the

system:

1. Length of the desired sheet in mm.

2. Diameter of the roller

3. Gear ratio

4. cutter on/off duration

5. Calibration



1.2.3 Application Background :

The following diagram shown is the application diagram

Figure 1.1 Application Background

Here as shown in the diagram the system has to control the right side belt

assembly by controlling the rollers such that rotation of the rollers provide the

forward motion of belt and hence the sheet. Here the rotation of the roller is such

that it provides the exact desired length of the sheet. Such controlling action of the

rollers and hence the entire right sided belt assembly is achieved by a servo motor

and servo drive with C2L unit. Here the C2L unit provides the derived pulse train

as per the user requirement to the servo drive. Here the servo drive is set to the

pulse position mode, such it gives the signal to servo motor in accordance with the

number of pulses in pulse train. Here the belt assembly on the right side, moves

with the constant speed along with the take up drum.



1.3

Now from the application background we come to know the handling of system

components. But there are many difficulties associated with the system, which

must be considered and also the provision of such difficulty must be provided as a

controlling action of system itself.

1.3.1 Operation Overview with possible arrangement : The entire system can be controlled by providing proximity switches as shown in

the figure. There can be mainly three proximity switches, one for starting the

cutting operation called start proximity, and rest two are the stop proximity

switches in the case of any failure. Here the proximity switches actually senses

the position of the dancing roller and hence controlling the cutting action.

OPERATION OVERVIEW AND PROBLEM DEFINITIONS

Figure 1.2 Operation Level With Possible Arrangement Here the operation starts with sensing of start proximity switch as the dancing

roller reaches the start level. The C2L unit generates the no. of pulses derived



according the calculation of the parameters and hence the servo motor rotates.

Here the dancing roller is having vertical motion under the gravitational force and

it also provides little tension to the sheet for avoiding the wrinkles in the sheet

which helps to maintain the exact length(**1).

1.3.2 Consideration for the Length of sheet : The following diagram shows how the measurement of the length of the sheet is

carried out.

Figure 1.3 Measurement Of The Length Of The Sheet

Here as shown in the figure the length of the sheet is to be measured from the

cutting edge. Here the cutter distance is varying for the different type of the cutter

assembly, which should be feasible for mechanical alignment. Each time the

system is turned on ,one has to take care about this cutter distance because it



simply turns out in the waste piece. So, if the cutter distance is negligible then

there is nothing to consider about the waste piece. This condition arises once at

the time of the system start up only. More details is given in the later chapter.

1.3.3 Problem Definitions & possible provisions :

How ever there are such possibilities for the wreaking up the sheet during the

running operation due to mechanical failure.. Such possibilities and their

provisions are listed below.

Case 1: Meanwhile the running condition, if the dancing roller reaches at the stop

level or say having displacement more than the clearance distance (**2). Such

condition occurs if the failure of the take up drum assembly ( or left side belt

assembly) takes place.

Provision : Such failure can be easily flag marked by providing the stop

proximity switch-1 at the stop level or at clearance distance as shown in the figure

1.2 . As soon as the stop proximity switch-1 has sensed ,the operation is halted till

the dancing roller reaches again to start level. Now as the dancing roller reaches to

the start level or say start proximity switch has sensed , the cutting operation

resumes with the remaining length to be cut.

Case 2: Meanwhile the running condition, if the dancing roller crosses the dead

end level. Such condition occurs if the sheet coming from the take up drum is

broken or the take up drum is empty. In this condition, if the roller is at the mid of

clearance level and the broken sheet comes, the roller falls down the ground,

giving signal to the start proximity switch. In such condition if there is no any

provision then the unit again starts giving the pulses and hence starts the cutting

sequence.



Provision : Such condition can be avoided by providing the stop proximity

switch-2 at the dead end level (**2) as shown in figure 1.2 . As soon as the roller

passes across the dead end level or stop proximity switch-2 has sensed, the

operation is halted. The system is halted till the new sheet material fed along with

the dancing roller as shown in the figure1.2 and waits for the start proximity

switch to sense.

Case 3: Consider a condition in which the cutter assembly which is also being

controlled by the C2L unit, fails during the operation.

Provision: In such condition, there is a provision of indicating whether the cutter

relay or solenoid is giving the output through the LED or some alarm. If the cutter

LED is glowing or the alarm is sounding after the rotation of the servo

mechanism, indicating the unit is working properly but the cutter assembly has

some mechanical failure . Hence we come to know also about the failure of cutter

assembly.

Hence the unit is able to sense the every possible mechanical failure. The

proximity switches are the backbone of the controlling of the entire system.

Hence the essential system is achieved logically. But only knowing the possible

failure and the possible solution it is worth saying that achieved the objective to

sense the mechanical failure. The corresponding hardware and the software must

have to assign for real time application. The hardware and the software portion for

the system are discussed in the following chapters.

(**1) Here the dancing roller is having only on vertical motion axis as in the actual application there is a guiding vane which provides the dancing roller only one vertical direction, although it is under the gravitational force only. (**2) Here the clearance distance and the distance between dead end level and the start level are absolutely depending upon the arrangement of the take up drum and conveyor belt assembly. Also the height of the conveyor belt assembly from the ground level must be considered. It is recommended to keep the clearance distance twice of the distance between the start and dead end level.



System Model

Hardware Description

Utilizations & calculations for uC

Circuit Diagrams & Trouble Shooting

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2.1 SYSTEM MODEL

Figure 2.1 System Block Diagram

Figure 2.2 System With Controlling Peripherals

As shown in the figure 2.1 the proximity switches are connected to the Opto-

isolation board. Here the proximity switches as well as the pulses and the cutter

relay are not connected directly to the controller for providing electrical isolation.

Here the LCD and the keyboard are directly connected to the controller.



2.1.1 System components :

• Transducers :Proximity switches ( M8 DC NPN Inductive Proximity

switch )

• Opto-couplers ( MCT2E )

• Microcontroller ( P89LPC932A1)

• Liquid Crystal Display ( XIAMEN GDM1602K )

• Key Board ( 3x 2 matrix )

• Relay ( operating at 5 v DC ) or solenoid

• Devices controlled

1) AC servo drive ( Yaskava G7 single phase )

2) AC servo motor ( Yaskava SGDM200H )

Transducers : Proximity switches

As discussed in the operation overview the proximity switches are the backbone

of the system. The total controlling action depends on the sensing of the

proximity switches. Even they are utilized in such a way that they can also sense

the mechanical failure.

Opto-couplers:

Opto-couplers are utilized for providing electrical isolation to microcontroller

from external peripherals, as microcontroller is very sensible to external noise.

Hence the Opto-couplers are the isolating medium through which the external

peripherals are connected to the microcontroller.

Microcontroller:

The microcontroller is the Heart of the proposed automation system. It

constantly monitors the digitized outputs of the proximity switches and takes the

predefined corresponding actions at that instant of time. In case such a situation

arises it activates the other peripherals to perform the controlled operation.



Display Unit:

A simple 2x16 Liquid Crystal Display is used to indicate the present status of the

parameters and respective values. The information is to be display in menu format

with corresponding action of the keyboard.

Key Board :

A simple 3x2 matrix keyboard is interfaced with the controller. The key board is

designed such that it generates the keyboard interrupt for respective key pressed.

Relay or Solenoid :

A simple low voltage relay or solenoid can be used to turn on the cutter assembly

as a part of controlling action.

2.1.2 Step followed in designing the system : Here three general steps can be followed to appropriately design such control

system.

Servo Drive controlling parameters

Step #1: Identify the controlling parameters important to production

It is very important to identify the parameters that are going to affect the operation

of the entire system.

Table 2.1 Importance Of Various Parameters

Sr no. Parameter to be considered Importance of the parameter

1. Servo parameter multiplier Indicates a single pulse to the servo motor is equal to

no of pulses from the C2L unit which is being

converted by servo drive. ( max 33 )

2 Precision pulses (bits) in

terms of 2^x

Indicates no of precision bits of the servo motor

encoder, required for feedback to drive (max 17)

3. Frequency The frequency of the pulse train outputted to servo

drive from the C2L unit, decides the speed of

operation. Range (1-70 KHz)



Mechanical parameters


4 Gear ratio From servo shaft to roller gear for length calculation

( max 10 )

5 Feed roller Diameter Outer diameter of roller surface for length calculation

( max 9999 mm )

6 Length Length of the sheet to be cut (max 9999 mm )

7 O/P time On/Off time duration of cutter ( max 9999 ms)

Calculative Parameters


8 Pulse count value No of pulses in a pulse train, which has to be fed to

the servo drive, derived form the above parameters

9 Offset length in um Required for the calibration, added or subtracted

from the actual length ( max 9999 um )

The above mentioned parameters must be followed by designed system with

accuracy and reliability .

• On sensing the start proximity switch the system must have to feed the

derived no of pulses to the drive, that rotates the servomotor resulting the

desired length.

Step #2 : Investigate the Control strategies

An important element in considering a control system is the control strategy that

is to be followed. Knowing the system objectives, application background and

operation overview and system parameters, we decide the controlling action to be

taken by the unit for the desired result.



• On sensing the stop proximity switch the system must have to hold the

entire operation with some indication, and again sensing on the start

proximity switch the remaining operation must have to complete.

• The system parameters can be easily changed according to user

requirement. The controlling action must be carried out according the

parameters, each time they are changed.

• Expand the number of measured variable and controlled devices so

that growth and changing needs of the production operation can be

satisfied in the future.

Step #3: Identify the software and the hardware to be used

It is very important that system functions are specified before deciding what

software and hardware system to purchase. The model chosen must have the

ability to:

• Provide a flexible and easy interface.

• It must ensure high precision measurement and must have the ability

to resist noise.

Hardware must always follow the selection of software, with the hardware

required being supported by the software selected. In addition to functional

capabilities , the selection of the hardware should include factors such as

reliability, support, previous experiences with equipment ( successes and failures),

and cost.



2.2

The following section gives the features of the hardware components with

functional descriptions.

HARDWARE DESCRIPTION

2.2.1 Transducers / proximity switches A transducer is a device which measures the real time physical quantity and

converts it into a signal which can be read by an observer or by an instrument/

Monitoring controlling of this system involves sensing the change in the position

of dancing roller which influence the cutting action of the desired length sheet.

The sensors used in this system are the proximity switches.

Figure 2.3 M8 DC inductive Proximity Switch

2.2.1.1 Features

• The Katlax M8 DC NPN inductive switch uses 10 to 30V DC supply with

sensing distance 8x8x2 mm. It has only three terminals +V, O/P, 0.

• It gives the output triggering signal on sensing the object with maximum

of 3 KHz sensing frequency.



2.2.1.2 Functional Description

• The inductive proximity switch works on the principle of changes in

resonant circuit caused by eddy current losses in the inductive material.

• The inductive proximity switch has four main components; The coil,

oscillator, detection circuit and output circuit.

• The oscillator generates a fluctuating magnetic field the shape of

doughnut around the winding of the coil that locates in the device’s

sensing face as shown in the following figure.

• When a metal object moves into the inductive field of detection, eddy

circuit builds up in the metallic object, magnetically push back, and

finally reduce the oscillation field. The sensor’s detection circuit

monitors the oscillator strength and trigger’s an output from the output

circuitry when a oscillator becomes reduced to a sufficient level. • As there are total three proximity switches are utilized and as they are

electrically isolated from controller , the output triggering signal are

given to the Opto-couplers , which give the signals to the controller.

• Two of them are connected parallel named stop proximity1 and 2.The

start proximity resumes the cutting operation each it senses, and on

detection of stop proximity switches the cutting operation is halted until

start proximity has sensed again.

Figure 2.4 Block Diagram Of Inductive Proximity Switch



2.2.2 The Opto-coupler The opto-coupler simply consists a diode and a phototransistor, whose base is

open and the conduction of the transistor depends on the light intensity falling on

the base junction ; provides electrical isolation between two devices. Hence they

are widely used in the industry for isolation purpose.

Figure 2.5 Opto-coupler MCT2E

2.2.2.1 Features

• The opto-coupler MCT2E from Texas Instruments, is simply a Gallium

Arsenide Diode infrared source optically coupled to a silicon npn

phototransistor.

• Base lead provided for conventional transistor biasing with high direct-

current transfer ratio.

• High voltage electrical isolation up to 1.5 KV with high speed switching.


• All the external peripherals are isolated through the opto coupler to the

microcontroller..

• Such isolation provides the immune to the noise as well as short circuit

protection and high voltage fluctuations from the peripheral devices.



• The output from the controller is connected to the anode of the diode and the

peripherals like cutter relay and the pulse train to servo drive are connected

to the collector of the transistor.

• The output from the proximity switch is connected to the anode and the

collector is biased through a resistor with 3.3V. The collector also connected

to interrupt pin of microcontroller. On triggering the proximity switch

output the transistor starts conducting pulling the biasing voltage to ground

and generating low level interrupt signal to the micro controller. As shown

in the following figure.

Figure 2.6 Connections Through Opto-coupler



2.2.3 The Microcontroller P89LPC932A1

2.2.3.1 Criteria For Choosing A Microcontroller

The basic criteria for choosing a microcontroller suitable for the application are:

1) The first and foremost criterion is that it must meet the task at hand efficiently

and cost effectively. IN analyzing the needs of a microcontroller-based

project, it is seen whether an 8-bit, 16-bit or 32 bit can best handle the

computing needs of the task most effectively. Among the other considerations

in this category are:

• Speed

•

: The highest speed that the microcontroller supports.

Packaging

•

: It may be a 40 pin DIP (dual inline package ) or a QFP

(quad flat package), or some other packaging format like TSSOP (thin

shrink small outline package ). This is important in terms of space,

assembling, and prototyping the end project.

Power consumption

•

: This is specially critical for application purpose

or rather say available power sources.

Cost per unit

• The number of I/O pins and the features of the controller.

: This is important in terms of the final cost of the product

in which a microcontroller is used.

• How easy it is to upgrade to higher performance or lower consumption

versions.

2) The second criterion in choosing a microcontroller is how easy it is to develop

products around it. Key considerations include the availability of an

assembler, debugger, compiler, technical support.

3) The third criterion in choosing a microcontroller is its ready availability in

needed quantities both now and in the future. Currently of the leading 8-bit

microcontrollers, the 8051 family has the largest number if diversified

suppliers. By supplier is meant a producer besides the originator of the

microcontroller. IN the case of the 8051, this has originated by Intel, several

companies also currently producing 8051 based microcontrollers.



Thus the microcontroller P89LPC932A1 by Philips semiconductors, satisfying the

criterion necessary for the proposed application is chosen for the task.

Figure2.7 Pin Diagram Of Microcontroller P89LPC932A1

The P89LPC932A1 is a single chip microcontroller , available in low cost

packages, based on a high performance processor architecture that executes

instructions in two to four clocks, six times he rate of standard 80C51 devices.

Many system level functions have been incorporated into the P89LPC932A1 in

order to reduce component count ,board space, and system cost.

2.2.3.2 Key Features Of P89LPC932A1:

• 8 Kb byte-erasable flash code memory organised into 1 Kb sectors and 64

byte pages.

• 256 byte RAM data memory, 512 byte auxiliary on chip RAM

• 512 byte EEPROM on chip allows serialization of devices, storage of set up

parameters, etc.

• Two analog comparators with selectable inputs and reference sources.



• Two 16 bit counter/ timers ( each may be configured to toggle a port output

upon a timer overflow or to become a PWM output ) and a 23 bit system

timer as a Real Time Clock ( RTC ).

• Enhanced UART with fractional baud rate generator, break detect, framing

error detection and automatic address detection; 400 KHz byte wide I2C

communication port and SPI ( Serial Peripheral Interface ) communication

port.

• Capture/Compare unit ( CCU ) provides PWM (Pulse Width Modulation ) ,

input capture and output compare functions.

• High accuracy internal RC oscillator option allows operation without

external oscillator components.

• 2.3 V to 3.6 V VDD operating range. I/O pins are 5 v tolerant.

• Serial flash In-Circuit Programming ( ICP ) allows simple production coding

with commercial EPROM programmers.

• Serial flash In-System Programming ( ISP ) allows coding while the device

is mounted in the end application.

• In-Application programming ( IAP ) of the flash code memory. This allows

changing the code in running application.

• Watchdog timer with separate on chip oscillator , requiring no external

components.

• Programmable port output configuration options: quasi bidirectional , open

drain, push-pull, input only.

• Eight keypad interrupt inputs. Plus two additional external interrupt inputs.

• Two data pointers

• Only +VDD ( power ) and –VSS ( ground ) connections are required to

operate the P89LPC932A1 when internal reset option is selected.



2.2.3.3 Block Diagram of P89LPC932A1 :

Figure 2.8 Block Diagram Of Microcontroller P89LPC932A1

The detailed functional description of different unit of microcontroller

P89LPC932A1 along with the schematic of the proposed system are given later in

this chapter.



2.2.4 Liquid Crystal Display (GDM1602K)

A liquid crystal display ( LCD) is a thin, flat display device made up of any

number of color or monochrome pixels arrayed in front of a light source or

reflector. Each pixels consists of a column of liquid crystal molecules suspended

between two transparent electrodes, and two polarizing filters, the axes of

polarity of which are perpendicular to each other. Without the liquid crystals

between them, light passing through one would be blocked by the other. The

liquid crystal twists the polarization of light entering one filter to allow it to pass

through the other.

Many microcontroller devices use ‘smart LCD’ displays to output visual

information. LCD displays designed around KS0066U MPU, are inexpensive,

easy to use, and it is even possible to produce a readout using 8x80 pixels of the

display. It has a standard ASCII set of characters and mathematical symbols.

For an 8-bit data bus, the display requires a +5V supply plus 11 I/0 lines . for a

4-bit data bus it only requires the supply lines plus seven extra lines. When the

LCD display is not enabled, data lines are in tri-state and they do not interfere

with the operation of the microcontroller.

Data can be placed at any location on the LCD. For 16x2 LCD, the address

locations are:

Table 2.2 Locations For Characters For LCD



2.2.4.1 Features :

The features include:

• 5x8 dots for each character with cursor.

• Built-in controller (KS0066U )

• Easy interface with 4-bit or 8-bit MPU

• +5V power supply ( also available for + 3 V )

• 1/16 duty cycle with inbuilt oscillator ( fosc 270 KHz )

• BKL to be driven by pin1,pin2, or pin 15, pin16 or A,K

• KS0066U function set instructions ( set display methods, set data length,

etc.)

• Inbuilt line segment driver for LCD

• Address set instructions to internal RAM

• Data transfer Instructions with internal RAM

Figure 2.9 Pin Diagram Of LCD



Table 2.3 Pin Description Of LCD

Pin no. Symbol External

connection Function

1 Vss

Power supply

Signal ground for LCM

2 Vdd Power supply for logic (+5V) for LCM

3 Vo Contrast adjust

4 RS MPU Register select signal

5 R/W MPU Read/ write select signal

6 E MPU Operation (data read/ write) enable signal

7~10 DB0~DB3 MPU

Four low order bi-directional three state data

bus line. Used for data transfer between the

MPU and LCM. These four are not used

during 4 bit operation.

11~14 DB4~DB7 MPU

Four high order bi-directional three-state data

bus lines. Used for data transfer between the

MPU

15 LED+ LED BKL power

supply

Power supply for BKL “A” (+ 4.2 V )

16 LED- Power supply for BKL “K” ( GND )


• The LCD display module is built in a LSI controller, the controller has two 8-

bit registers, an instruction register ( IR) and a data register ( DR )

• The IR stores the instruction codes, such as display clear and cursor shift, and

address information for display data RAM ( DDRAM ) and character

generator RAM (CGRAM). The IR can only be written from the MPU.

• The DR temporarily stores data to be written or read from DDRAM or

CGRAM. When address information is written into the IR, then data is stored

into the DR from DDRAM or CGRAM.

• By the register selector ( RS ) signal, these two registers can be selected.



Table 2.4 Register Selection For LCD

• When the busy flag is 1, the controller LSI is in the internal operation mode

and the next instruction will not be accepted. When RS=0 and R/W=1, the

busy flag is output to DB7. The next instruction must be written after ensuring

that the busy flag is 0.

• Address counter (AC) assigns addresses to both CGRAM and DDRAM.

• DDRAM is used to store the display data represented in 8-bit or 4+4 bit

character code. Its extended capacity is 80x8 bits or 80 characters.

• The CGRAM generate 5x8 dot or 5x10 dot character patterns from 8-bit

character codes, and the user can rewrite character by program. For 5x8 dots,

eight character patterns can be written, and for 5x10 dots, four character

patterns can be written.

• Here for the proposed system the LCD is used in the four bit-mode as per the

application requirement. Here only higher data bits DB4~DB7 lines are

connected to the controller , and all the instructions as well as 8-bit data are

being sent through higher and lower nibble.



Table 2.5 Instruction Table For LCD



2.2.5 Keyboard

The predominant interface between humans and controller is the keyboard.

Keyboards range in complexity from the “up-down” buttons used for elevators to

the personal computer QWERTY layout, with the addition of function keys and

numeric keypads. The one constant in all keyboard applications is the need to

accommodate the human user. Human beings can be irritable. They have little

tolerance fro machine failure ; watch what happens when the product isn’t ejected

from the vending machine. Sometimes they are bored by routine, or even hostile

towards the machine . The hardware designer has to select keys that will survive

in the intended environment. The programmer must write code that will

anticipate and defeat inadvertent and also deliberate attempts by the human to

confuse the program.

It is very important to give instant feedback to the user that a the key hit has been

acknowledged by the program. The user must know that the key has been

recognized through any indicator.

2.2.5.1 Key switch Factors

The keyboard application program must guard against the following possibilities:

• More than one key pressed ( simultaneously or released in any sequence )

• Key pressed and held

• Rapid key press and release

All of these situations can be addressed by hardware or software means; soft ware

, which is the most cost effective, is emphasized here.

The universal key characteristic is the ability to bounce: the key contacts vibrate

open and closed for a number of milliseconds when the key is hit and often when

it is released. These rapid pulses are not discernible to the human, but they last a



relative eternity in the microsecond- dominated life of the microcontroller. Keys

may be purchased that do not bounce, or keys may be debounced with RS flip-

flops or debounced in software with time delays.

2.2.5.2 The Schematic and functional description

Figure 2.10 Schematic Of Keyboard

Functional description :

• The keyboard shown in the above schematic is a 3x2 matrix keyboard.

• Initial value to the port pin is high for all the port pins (P0.1 to P0.5)

• If any key is pressed the corresponding row and column is pulled down to the

GND and here the keyboard interrupt is generated

• Here the keyboard SFRs are utilized such a way that only row can generate the

keyboard interrupt



• The pattern on the keyboard is to be compared and then the corresponding key is

identified from the status of that input pattern

• The SFRs used for handling the key-board are KBMASK (Key Board Masking),

KBCON (Key Board Control) ,and KBPATN ( Keyboard Pattern)

KBMASK is set to 0E h for generating interrupt, allowing only P0.1, P0.2

and P0.3 to generate Keyboard interrupt

KBPATN is set to 0E h for allowing all inputted pattern from keyboard

except 0E h

KBCON is set to 00 h for clearing the KBI flag and pattern selecting bit

(NOT equal to the value which has been set in KBPATN register ).

• The corresponding action is to be taken as a key is pressed with debounce delay of

30 msec after each press. The same will be repeated if the key is held for a while.

(For more details on Keyboard interrupt handling refer the data sheet of

P89LPC932A1 attached.)



2.2.6 Relay

A relay is an electrical switch that opens and closes under the control of another

electrical circuit. In the original form, the switch is operated by an electromagnet

to open or close one or many sets of contacts. Because a relay is able to control an

output circuit of higher power than the input circuit, it can be considered to be, in

a broad sense ,a form of an electrical amplifier.

Figure 2.11 A Relay

Despite the speed of technological developments, some products proved useful to

many designers who needed to switch up to 10A, whilst using relatively little

PCB area.

2.2.6.1 Relay contacts and types of relay :

Since relays are switches, the terminology applied to switches is also applied to

relays. A relay will switch one or more poles, each of whose contacts can be

thrown by energizing the coil in one of three ways:

1. Normally open (NO) contacts connect the circuit when the relays is activated;

the circuit is disconnected when the relay is inactive. It is also called FORM-

A contact or “make” contact.

2. Normally closed (NC) contacts disconnect the circuit when the relay is

activated ; the circuit is connected when relay is inactive. It is also called

FORM-B contact or “Break” contact.

3. Change over or double throw contacts control two circuits; one normally

open contact and one normally closed contact with a common terminal. It is

also called a FORM-C or “transfer “ contact.



Figure 2.12 Types Of Relay

2.2.6.2 Factors to be considered for selecting a relay

You need to consider several features when choosing a relay :

1. Physical size and pin arrangement : If you are choosing a relay for an existing

PCB you will need to ensure that its dimensions and pin arrangement are suitable.

You should find this information in the supplier's catalogue.

2. Coil voltage : The relay's coil voltage rating and resistance must suit the circuit

powering the relay coil. Many relays have a coil rated for a 12V supply but 5V

and 24V relays are also readily available. Some relays operate perfectly well with

a supply voltage which is a little lower than their rated value.

3. Coil Resistance : The circuit must be able to supply the current required by the

relay coil. You can use Ohm's law to calculate the current:

Relay coil current = Supply voltage

Coil resistance

http://www.kpsec.freeuk.com/ohmslaw.htm



For example: A 12V supply relay with a coil resistance of 400 passes a current

of 30mA. This is OK for a 555 timer IC (maximum output current200mA), but it

is too much for most ICs and they will require a transistor to amplify the current.

4. Switch ratings (voltage and current) :The relay's switch contacts must be

suitable for the circuit they are to control. You will need to check the voltage and

current ratings. Note that the voltage rating is usually higher for AC, for example:

"5A at 24V DC or 125V AC".

5. Switch contact arrangement (SPDT, DPDT etc): Most relays are SPDT or

DPDT which are often described as "single pole changeover" (SPCO) or "double

pole changeover" (DPCO).

2.2.6.3 Need of protection diode

Transistors and ICs (chips) must be protected from the brief high voltage 'spike'

produced when the relay coil is switched off. The diagram shows how a signal

diode (e.g. 1N4148) is connected across the relay coil to provide this protection.

Note that the diode is connected 'backwards' so that it will normally not conduct.

Conduction only occurs when the relay coil is switched off, at this moment

current tries to continue flowing through the coil and it is harmlessly diverted

through the diode. Without the diode no current could flow and the coil would

produce a damaging high voltage 'spike' in its attempt to keep the current flowing.

2.2.6.4 Functional description

• The output from micro controller is connected to the base of the transistor BC548

through a resistor.

• The relay coil is connected between the +5V supply and the collector of the

transistor as shown in the figure.

• Before the output from controller triggers the transistor; it is in a cutoff level and

there is no charge across the relay coil as the circuit does not complete. Hence

relay is said in off state.

http://www.kpsec.freeuk.com/trancirc.htm#chip



• Now as the controller pin goes high the transistor triggered and completes the

circuit and hence the charge across coil exists , switching the relay in on state.

• The relay remains in on state as long as the microcontroller pin is held high.

• On the other end the cutter assembly is connected between NO and COM pins,

controlling the on/off control of the cutter.

• As the relay turns on consequently it switches the cutter and the cutting of the

sheet takes place.

• Here the relay switch only controls the on/off state of cutter assembly, and the

on/off time duration depends on the type of cutter assembly, as well as cutting

duration. This can be variable for different cutter assembly , can be changed as

per the requirement.

Figure 2.13 Relay Connection With Protection Diode



2.3

2.3.1 The main equation : The main objective of the proposed system is to derive the number of pulses in

accordance with parameters as given in table 2.1. Here the number of pulses is

such that it brings the exact rotation of the servo motor for desired length to cut.

The exact no of pulse is calculated by the following :

Servo parameter multiplier : _ _ ( max of 33 )

Precision pulses (bits) in terms of 2^X : _ _ ( max of 17 )

Feed roller diameter : _ _ _ _ in mm ( max of 9999 mm)

Required Length of the sheet : _ _ _ _ in mm ( max of 9999 mm )

Offset length : _ _ _ _ in um ( max of 9999 um )

Gear ratio : _ _ ( max of 10 )

Now, from above parameters we can find displacement length per revolution for

feed roller (DLR) :

UTILIZATIONS & CLCULATIONS FOR µC

The servo motor has the position encoder. This encoder has the precision bits in

terms of 2^ (X+1). This encoder is connected to the servo drive, gives the

position status of the motor shaft. One has to give the pulses to the motor such

that rotation of motor occurs in a multiple of this precision bits. This work is

actually carried out by the MP controller (refer system objectives 1.2.2). Hence

we are multiplying the precision pulses (bits) for having the virtual management

of that MP controller for our proposed unit. Also the servo parameter multiplier is

a feature of that MP controller which informs the servo drive; a single pulse to



the servo motor should equal to no of pulses from the MP unit. Hence we also

use this feature for deriving final pulses per revolution.

So, the calculation for the servo parameters is carried out by following equation:

Now, number of pulses required per revolution of servo motor is given by the

following equation :

Apart from this , additional offset is required as the above equation only meets

the truncated figure. So the offset value in the length is added in terms of

micrometer for more precise value.

So the actual pulse count is now carried out from the following equation :



2.3.2 The Clock management and frequency calculation :

Figure 2.14 Block Diagram Of Oscillator Control Of uC P89LPC932A1

The microcontroller uses an enhanced 80C51 CPU which runs at 6 times the

speed of standard 80C51 devices. A machine cycle consists of two CPU clock

cycles, and most instructions execute in one or two machine cycles. The device

has several internal clocks as shown in the above figure.

• OSCCLK – Oscillator Clock - input to the DIVM ( Division by Magnitude )

clock divider. OSCCLK is selected from one of four clock resources and can also

be optionally divided to a slower frequency ( see section “ CPU clock (CCLK)

modification: DIVM register in the attached datasheet of uC .)

Note: OSCCLK is denoted by fosc.



• CCLK- CPU Clock- output of the DIVM clock divider. There are two CCLK

cycles per machine cycle, and most instructions are executed in one to two

machine cycles ( two or four CCLK cycles).

• RCCLK – the internal 7.373 MHz RC oscillator output.

• PCLK- Peripheral Clock – clock for the various peripheral devices and is

CCLK/2.

Here we are using only internal RC oscillator using default factory settings, hence

RCCLK = 7.3728 MHz +/- 2 %. Now as we are not utilizing any other clock

source except RCCLK, the OSCCLK is equal to the RCCLK.

RCCLK = OSCCLK = fosc = 7.3728 MHz = 0.135 us per cycle

The OSCCLK frequency can be divided down ,by an integer , up to 510 times by

configuring a dividing register , DIVM, to provide CCLK. This produces the

CCLK frequency using following formula :

CCLK frequency = fosc / (2 N ) where: N is the value of DIVM

Since N ranges from 1 to 255 , the CCLK frequency can be in the range of fosc to

fosc / 510. For N = 0, CCLK = fosc.

Now fro the DIVM, the value of N is set to default zero i.e. N=0, and hence the

CCLK is also equal to RCLK.

So CCLK= fosc = 7.3728 MHz

Now PCLK = CCLK / 2

= 7.3728 / 2 MHz

= 3.6864 MHz

= 0.271 us per cycle.

( For more details on clock management please refer the user manual of

P89LPC932 attached.)



2.3.3 The CCU and the calculation of Pulse train output frequency :

CCU – Capture Compare unit

Here the dominant objective is to generate a pulse train of the desired frequency

range. Now the CCU unit of uC provides asymmetrical or symmetrical PWM

which can be utilized to generate the desired pulse train as it can provide the

toggling of output port pin.

To utilize the CCU for such application we must understand the timing sequence

and control of CCU timers along with timer frequency.

Figure 2.15 Capture Compare Unit Block Diagram

Here only output compare unit is enabled. The output compare channel A (OCA)

is enable. Whereas the other three channels OCB,OCD,OCC are disable. So PWM

output is carried out on pin OCA (P2.6). The input capture unit is disabled.

The output capture unit is initialized in symmetrical PWM and with desired

frequency count value for CCU timers.



The CCU runs on the CCUCLK , which can be either PCLK in basic timer mode

or the output of a PLL as shown in figure 2.14. The PLL is designed to use a

clock source between 0.5 MHz to 1 MHz that is multiplied by 32 to produce a

CCUCLK between 16 to 32 MHz in PWM mode . The PLL contains a 4-bit

divider to help divide PCLK into a frequency between 0.5 to 1 MHz.

PLL freq. = PCLK / N+1 where, N= pre-scalar value

= 3.6864 / 4+1 here ,setting 4 bit divider to value to 4 d

= 0.737280 MHz

CCUCLK freq . = 32 x PLL freq.

= 32 x 0.737280 MHz

= 23.592960 MHz

= 42.38 ns per cycle

Here only output compare unit is enabled. The output compare channel A (OCA)

is enable. Whereas the other three channels OCB,OCD,OCC are disable. So PWM

output is carried out on pin OCA (P2.6).The input capture unit is disabled. The

output capture unit is initialized in symmetrical PWM and with desired frequency

count value for CCU timers.

Figure 2.16 CCU PWM Symmetrical Mode



Here the CCU timer needs only one CCUCLK cycle for increment or decrement.

But as we are utilizing symmetrical PWM, the output pin OCA will toggle on the

each compare fro both incrementing and decrementing direction as shown in the

figure 2.15. So here we are using two CCUCLK cycle or doubling the required

freq. virtually and finding the timer count value for resetting on overflow or

underflow. But the toggling occurs at the half the timer overflow value i.e. having

the desired frequency pulse on each compare.

So two CCUCLK cycle tc = 2 x 42.38 ns = 84.77 ns

Foe example, let the desired freq. of pulse train is fd = 1KHz

then pulse duration = 1 / fd = td = 1 ms

Now count value for timer = td / tc

= 1 ms / 84.77 ns

= 11796 decimal

= 2E14 Hex

so the timer reset value on overflow or under flow is = 2E14 Hex

and the compare value is exactly half the timer reset value = 170A Hex

So we can derive the count value for timers for desired freq. of pulse train as

shown in above method. The following table shows the timer value derived for

desired frequency in hex for the entire frequency range.

Table 2.6 CCU Timer Value For Different Frequency

Frequency

KHz

Timer count value

Decimal Equivalent Hex value

1 11796 2E14

2 5898 170A

3 3932 0F5C

4 2949 0B85



Frequency

KHz

Timer count value


5 2359 0937

6 1966 07AE

7 1685 0695

8 1475 05C3

9 1310 051E

10 1180 049C

11 1072 0430

12 0983 03D7

13 0908 038C

14 0842 034A

15 0786 0312

16 0737 02E1

17 0693 02B5

18 0655 028F

19 0620 026C

20 0590 024E

21 0562 0232

22 0532 0218

23 0512 0200

24 0492 01EC

25 0472 01D8

30 0393 0189



Frequency

KHz

Timer count value


40 0294 0126

50 0236 00EC

60 0196 00C4

70 0168 00A8

This frequency is actually frequency of pulse train, whose no of pulses are derived

through the parameters considered. This frequency is actually converted to the

speed per revolution for servo motor. This conversion is done by servo drive in

pulse position mode.





2.3.4 The RTC and the calculation of cutter on/off time duration :

RTC – Real Time Clock

The Real Time Clock is used to generate an interrupt on each msec delay as the

timer of the RTC is configured , until the cutter on/off duration time is over.

Hence provides the exact duration for cutting action of the sheet.

Figure 2.17 Block Diagram Of RTC Unit

As the timer underflows each time the RTC interrupt is generated and

corresponding interrupt routine is being called.

Here the value of RTC timer is selected such that it decrements and reloaded with

the same value after 1 msec.



Now the calculation for timer is carried out as following :

The RTC unit contains a 23 bit timer/counter , including a 7-bit pre-scalar whose

reset value is 1111111 binary. Hence the timer value is combination of

RTCH,RTCL,1111111 binary.

RTC clock source = CCLK = 7.3728 MHz

So one CCLK cycle time tcclk = 0.136 us

Now for one msec delay counter value = 1 ms / 0.136 us

= 7372.8 d

~ = 7373 d

But the nearest possible value less than the derived one is 7295 d = 001C7F H

Since every time the timer underflows its prescalar value always set to the default

value ‘111 1111’ binary. Hence last seven digits of the timer are always.

So, Timer higher byte TH2 = 00 H

Timer lower byte TL2 = 39 H

So, actual timer value = 00 H + 38 H + 111 1111 B = 7295 d

Suppose the cutter on/off duration is 1000 msec, then after every 1 msec the

timer underflows and the RTC interrupt is generated, incrementing a counter

variable by one till 1000 reached. By this duration the cutter assembly is held on

and after it is switched to off and the counter variable again set to zero. Hence the

exact time duration is achieved for cutter assembly.

Note: The RTC timer is set to on only after the pulse train transmission is over.





2.4

2.4.1 Supply Board Before going to see all the system main board, first we are going to see the power

supply board, which is very essential for the system. The supply must be stable

under the operation conditions as well as application environment. The input to

the supply board is 230V AC, 50 Hz only ,and must able to give output of 3.3 V,

5 V, and 24 V DC with suitable load current capacity. The following diagram

shown is of the supply board :

CIRCUIT DIAGRAMS & TROUBLE SHOOTING

Figure 2.18 Circuit Diagram Of Supply Board



2.4.1.1 Circuit Functionality :

• The power supply section consists of step down transformers of 230V 50 Hz

primary to 12-0-12V secondary. The stepped down voltage is then rectifier by two

separate bridges made of diodes 1N4007. The upper one rectifies 12-12 V AC to

24 V DC, and the lower one rectifies 12-0 V AC to 12 V DC from which 3.3 V

and 5 V DC are generated.

• The high value capacitors to the input of voltage regulators charge at a slow rate

as the time constant is low, and once capacitors charged there is no resistive path

for discharge. This gives a constant value of DC voltage.

• IC 7805 is used for regulated supply of +5 V , IC 7824 is used for regulated

supply of + 24 V, and LM317 is used for regulated supply of +3.3 V; in order to

prevent any fluctuations. As shown in the figure 2.17 the filter capacitors

connected after these ICs filters the high frequency spikes. The capacitors are

connected in parallel with supply and common so that spikes filter to common,

gives stability to the supply circuit.

• Here the connector J1 is actually provided for LEDs for the indication whether the

supply line is working or not, and LEDs are actually connected to the front face of

the system through six lines cables.

• This board supplies 24 V for external use for servo motor, 3.3 V for controller,

and 5 V for LCD and the external relay board with maximum of 1 A current for

load .

• The voltage controller ICs are used with heat sinks for increasing heat radiation

area , hence avoiding overheat problems.



2.4.1.2 Trouble shooting :

If you are not getting desired output DC voltages u need to diagnose the actual

problem. You should go with the following steps :

Step I : Very first step is to check the circuit as per the circuit diagram shown

in the figure 2.17.

Step II : Starting with the Transformer first, check with DMM at secondary

terminals whether you are getting the known 12-0-12 AC voltages.

Step III : Check DC voltages at the output of each bridge rectifier. For the

bridge rectifier 1 it should be more than 24 V DC and for bridge rectifier 2 it

should be more than 12 V DC. If it is not then check the connections again.

Still if you are not getting then check each diode using the DMM ( applying

forward and reverse bias).

Step IV : Check the voltages across the input capacitors, they must be same as

at the rectifier ends, otherwise it indicates that the capacitor is weak, need to

replace.

Step V: Now check the pins of the voltage regulator ICs. If any two pins of

any IC is short circuited then need to replace that IC.

Step VI : Now check the voltages across the output capacitors, should be

same as the desired ones, otherwise need to replace that capacitor.

Step VII : Check whether the voltage regulator is overheated or not, if so then

immediately switch off the supply and replace the output capacitor with higher

value capacitor (voltage capacity of that capacitor should be higher than that

desired voltage level ).



2.4.2 Main Board

Now the most essential part of the system is the microcontroller , hence its

connection to peripheral devices. The board must be as compact as possible; easy

to detach the components as well as the board , for maintenance and repairing

purpose. The board should be designed such that replacement of the external

peripherals can be possible, or rather say it can be used as the general purpose

board with the microcontroller. The board should be designed such that

programming of the microcontroller can easily be done.

Figure 2.19 Main Board With uC P89LPC932A1

** here in actual case the LCD is connected through the 16 pin cable to the controller, which is not shown in the figure, to understand the exact connections of LCD.




The figure shows the connection to the port pins of microcontroller. Actually the

microcontroller is having TSSOP package, hence the size of the controller shown

is different than the actual one but the connections remain same.

• Port configurations :

All but three I/O port pins on the P89LPC932A1 may be configured by software

to the one of four types on a pin-by-pin basis, as shown in table 2.7. These are :

quasi-bidirectional , push-pull, open drain, and input only. Two configuration

registers for each port select the output type for each port pin.

P1.5 (RST- low active) can only be an input and cannot be configured.

P1.2 (SCL/T0) and P1.3 (SDA/ INT0 low active) may only be configured to be

either input-only or open drain.

Table 2.7 Port Output Configuration Modes

PxM1.y PxM2.y Port Output mode 0 0 Quasi-bidirectional (QB) 0 1 Push-pull (PP) 1 0 Input only(IN-high impedance) 1 1 Open drain (OD)

Quasi-bidirectional : This can be used both as an input and output without the

need to reconfigure the port. This is possible because when the port outputs a

logic high, it is weakly driven, allowing an external device to pull the pin low.

When the pin is driven low it is driven strongly and able to sink a large current.

There are three pull-up transistors in the quasi-bidirectional output that serve these

different purposes.



Open drain : The open drain output configuration turns off all pull-ups and only

drives the pull-down transistor of the port pin when the port latch contains a logic

0. To be used as logic output, a port configured in this manner must have external

pull-up, typically a resistor tied to VDD. The pull-down for this mode is the same

as for the quasi-bidirectional mode.

Input only: The input only configuration has only a Schmitt-trigger with a glitch

suppression circuit.

Push-pull: The push-pull output configuration has the same pull-down structure

as both the open drain and the quasi-bidirectional output modes, but provides a

continuous strong pull-up when a port latch contains a logic 1. The push-pull

mode nay be used when more source current is needed from a port output.

Now according to the requirement we can configure the each port pin. The

following table shows the port pin configuration along with peripherals

connected.

Table 2.8 Port Output Configuration

PxM1.y PxM2.y Mode Port pin

Physical pin Peripheral

Port 0 configuration X (0) X (0) X (QB) P0.0 03 ----------

1 0 IN P0.1 26 Keyboard (row-0) 1 0 IN P0.2 25 Keyboard (row-1) 1 0 IN P0.3 24 Keyboard (row-2) 1 0 IN P0.4 23 Keyboard (column-0) 1 0 IN P0.5 22 Keyboard (column-1) 1 0 IN P0.6 20 Control bit / stop proximity

X (0) X (0) X (QB) P0.7 19 ----------- P0M1

= 7E H P0M2 = 00 H



PxM1.y PxM2.y Mode Port pin

Physical pin Peripheral

Port 1 configuration 0 0 QB P1.0 18 TxD 1 0 IN P1.1 17 RxD

X (1) X (0) X ( IN ) P1.2 12 ----------- 1 0 IN P1.3 11 EXTI0- stop proximity 1 0 IN P1.4 10 EXTI1-start proximity 1 0 IN P1.5 06 Reset switch 0 0 QB P1.6 05 LCD- RW 0 0 QB P1.7 04 LCD- RS

P1M1 = 3E H

P1M2 = 00 H

Port 3 configuration X (1) X(0) X (IN) P3.0 09 EXT CRYSTAL ** X (1) X(0) X (IN) P3.1 08 EXT CRYSTAL** P3M1 |= 03 H

P3M2 &= FC H

Port 2 configuration 0 0 QB P2.0 01 LCD (Data-0) 0 0 QB P2.1 02 LCD (Data-1) 0 0 QB P2.2 13 LCD (Data-2) 0 0 QB P2.3 14 LCD (Data-3) 0 0 QB P2.4 15 LCD ( Enable) 0 0 QB P2.5 16 Pulse on status LED 0 1 PP P2.6 27 PWM / OCA – pulse o/p 0 0 QB P2.7 28 Cutter on/off to x’nal board

P2M1 =00 H

P2M2 = 40 H

** here in this system we are using the internal RC oscillator, so we don’t need to connect a crystal externally, but the default values for P3M1 = 01 H and P3M2 = FC H , although we are not using the crystal. So we are keeping the default status although using internal RC oscillator.

• Here as shown in the figure 2.16, the peripherals are connected through

connectors only.



• The potentiometer of the 5 kΩ at the LCD pins is provided for the intensity of the

pixels. You can vary the intensity as one can read the content properly.

• The transistor 2N2369 is a very high speed switching transistor ,gives the pulled

up out put from the pulses outputted by pin P2.6 to the servo motor.

• The programming ports are provided for ICP programming, where programming

port 1 is used for programming data to the controller and programming port 2 is

used for triggering the microcontroller in the programming mode using precise

sequence of reset pulses along with supply and ground. ( For more information on

ICP programming please read the manual attached fro P89LPC932A1.)

• The external board connector is actually used to connect the external board which

is an isolating board, through which the proximity switches and cutter relay is

connected. It will be more clear when we see the circuit diagram of external

board.

2.4.2.2 Circuit Trouble shooting :

If you are not getting desired output or functionality with the main board then

have to diagnose the actual problem. You should go with following steps :

Step I : First of all u have to check whether the microcontroller is working properly

or not. For that u have to give the supply (+ Vdd and GND ) and check the status of

port pins P0.6, P2.5, P2.7 ;must be at logic ‘0’. Another way to identify this is to

check whether the program loader is able to identify the device (microcontroller )

itself and properly able to load the program. If not so you have to replace the

microcontroller.

Step II : After that check the connectivity of all the connections with the help of

DMM as shown in the figure 2.18. particularly check the connectivity of controller

pins to the connector pins.

Step III : If you are not getting the pulse output at the connector, check the pin P2.6

using CRO, if pulse is there then you have to check transistor 2N2369. Still if you are

not getting the pulse you have to replace that transistor.



2.4.3 Key Board

Key board is a interface through which, human can communicate to the machine.

Here for the proposed system key board should be a X-Y matrix type. The matrix

is most efficient when arranged as a square so that N leads for X and N leads for

Y can be used to sense as many as N x N keys. Matrices are the most cost

effective for a large number of keys. Here we need total 6 no of keys to integrate

the desired action with microcontroller with maximum of 5 port pins.

Figure 2.20 Keyboard Circuit Diagram

** here the key board also consists the three power indicating LEDs not shown in the figure.




• Here the circuit actually consists of a logical 3x2 matrix. Here the diodes are used

for providing the initial all the pins high as they are not conducting when the

switch is not pressed.

• The key is a 4 pin push to on type switch for which two pins are short circuited

as shown in the figure. A two pin push to on switch can also be used, with a small

change; have to remove the short circuiting path.

• Initially diode is not conducting or say in a free wheeling mode hence all rows

and columns are initially at high level. Now whenever the key is pressed the

diodes start conducting as the cathode is now connected to the ground and pulls

down the corresponding row and column to zero ( neglecting drop voltage of 0.57

V ). This triggers the port pin and according to that pulled down row and column ,

the pressed key is detected and corresponding action is to be taken by micro

controller.

• Here only the corresponding row and column is pulled down to zero because the

connections of diodes as shown in the figure 2.19 prevents a path to the ground,

hence not affecting other rows and columns keeping them to the high level (+3.3

V).

• Here the drop out voltage of 0.6 V of diode is neglected as the low level threshold

voltage for the controller pin is VTH(LH) = 0.3 VDD = 0.3 x 3.3 = 0.99 V which is

grater than the 0.6 V so the drop voltage is negligible to interpret the logic low

level ( ~ 0 V ).

• Here the supply for the key board is carried out from the main board.

• The corresponding action is to be taken as the key is pressed as shown on the

above figure with row and column downs to zero; in accordance with the Key

board interrupt SFRs.

• The resistors provided for each row and columns are actually for current limiting

as the input current sink capacity of the controller pin is low as well as the same

source is used for the microcontroller. The key board hardly draws the current of

5 mA.



2.4.2.2 Circuit Trouble shooting :

If you are not getting desired output or the defined action is not being executed

after pressing the key from the keyboard and the main board is working properly

then need to diagnose the actual problem with the keyboard. You should go with

the following steps :

Step I : First disconnect the key board from the main board.

Step II : Check all connections and apply +3.3 V and GND to the corresponding pins

as shown in the figure 2.19.

Step III : Now check the status of all pins for rows and columns. Initially they must

be at high level. You can do this by checking the voltage level between that particular

pin and GND using DMM.

Step IV : Now press all the keys one by one. The corresponding row or column pin

must pulled down at logic ‘0’ or the voltage between that pin and GND should be zero

( neglecting the dropout voltage of 0.6 V ). If you are not finding such status change,

then check the diodes of that row or column pins using DMM .

Step V : If diodes are working properly and still you are not getting the exact output ,

then check the connectivity between GND pin and pin 2 of the key. If they are found

short circuited without pressing the key then the switch is damaged you have to

replace that switch. Again check the conductivity between pin 1 and 2 (or 3 and 4) of

the key. It should not conducting if the key is not pressed otherwise replace the

switch.



2.4.4 External Board

The external board is divided in two part the first part consists the opto-isolation of

proximity switches, and the second unit consist the isolation of cutter relay. The

provision behind this is the switching of cutter relay at higher voltage and current value

can damage the proximity switches if the connections to the connector are not made

properly.

2.4.4.1 External Board 1 :

Figure 2.21 Circuit Diagram Of External Board-1

2.4.4.1.1 Circuit Functionality:

• Here the proximity switches are connected to the 3 pin connectors as shown in the

figure. Here two stop proximity switches are connected parallel to the same part.

• The three terminals are provided (+24 V, O/P, GND ) fro proximity switches and

the O/P terminal is connected to the anode of the opto-coupler MCT2E through a



10 kΩ resistor. The 3.3 kΩ resistor is provided for proper biasing of the collector

of the opto-coupler transistor .

• Initially collector output of the proximity switch is high. Whenever the proximity

senses it triggers the diode of the opto-coupler and , will conduct the transistor

leading the supply to the ground switching to the low level, which will trigger the

interrupt pin of the microcontroller.

• The supply for opto-coupler transistor is carried out from the main board through

the connector as shown in the figure 2.20 .

• The 24 V supply is directly provided so that no other external supply is required

for proximity switches.

• This 5 pin connector is connected to the first five pins of 10-pin buck strip male

connector of the main board.

• This board provides an opto-electrical isolation for microcontroller and also

suppress the noise coming from external environment through high voltage

proximity switches.

2.4.4.1.2 Circuit Trouble shooting :

For trouble shooting of the external board1 you should go with following steps :

Step I : As this board is connected to the external peripherals and if you are

finding some problem, first of all you have to check whether the proximity

switches are working properly or not. For that provide the supply to the proximity

switches, take a metal sheet and bring it near the proximity switch, the output

terminal should go high.

Step II : Now check all connection as shown in the figure 2.20.

Step III : At the connector pins the now check the status . Initially they must be

at high level. You can do this by checking the voltage level between that

particular pin and GND using DMM.



Step IV : The CNTRL, stop proxi and start-proxi pin are high (+3.3 V) till the

proximity switch has not sensed. Once the switch has sensed, the level should be

pulled down to the GND (0 V between that pin and GND pin).

Step V : Now for the opto-coupler, apply the +24 V and GND to anode and

cathode respectively ( pin 1 and 2 ) . Now using DMM check the voltage level

across collector and emitter it should be 0.6 V or less ( forward drop out voltage ).

Now remove the supply from anode or cathode, the LED will turn off and the

voltage level across collector and emitter should be 3.3 V. If it is not so then you

have to change the Opto-coupler IC.

2.4.4.2 External Board 2 :

Figure 2.22 Circuit Diagram Of External Board 2.



2.4.4.2.1 Circuit Operation :

• The last pin of 10-pin buck strip male connector , a cutter output triggers the two

transistors BC548. The transistor Q1 is used to trigger the cutter relay an

transistor Q2 is used to trigger the opto coupler. Here u can directly connect the

LED which is for the cutter relay on/off indication without using the opto-coupler.

• Here transistors Q1 and Q2 are provided because the load current capacity or say

driving capacity of the microcontroller pin output is low. Hence we require to

pull up the driving capacity through the transistors.

• Here the relay coil is connected between +5 V and the collector of transistor

Q1.The freewheeling or protection diode is connected across the relay coil to

provide the discharge path.

• The capacitors at the supply connector are provided to reduce the flickering or

ripples while relay switching.

• Now initially the supply path for charging the relay coil as well as the path for

opt0-coupler LED is not completed , as the transistors Q1 and Q2 are not

conducting

• When the cutter output pin goes high at the end of pulse train, both the transistors

Q1 and Q1 triggers simultaneously, completing the path- triggers the relay coil to

charge and switching in the on state. At the same time the LED also on when the

transistor Q2 is conducting.

• The relay and the LED remains on till the cutter output is high according to the

time delay is set.

2.4.4.2.2 Trouble shooting :

for trouble shooting of the external board2 you should go with the following

steps:

Step I : check all the connection as shown in the diagram 2.21.

Step II: Now check the transistors BC548 , the voltage across collector and

emitter should be 5 V.



Step III : Now for the opto-coupler, apply the +5 V and GND to anode and

cathode respectively ( pin 1 and 2 ) . Initially the LED of opto-coupler is off, if the

cutter pin goes high , it triggers both the transistors Q1,Q2. Now using DMM

check the voltage level across collector and emitter it should be 0.6 V or less (

forward drop out voltage ). Now remove the supply from anode or cathode, the

LED will turn off and the voltage level across collector and emitter should be 5 V.

If it is not so then you have to change the Opto-coupler IC.

Step IV : If the relay is not triggering, first apply the 5 V across the coil of the

relay, you will immediately hear a knocking voice of the relay and the output

terminals are now short circuited; if it is not then change the relay.

Step V: Now still the relay is not switching then, check the protection diode

across the coil terminals. Now check the voltage level across collector and emitter

of the transistor Q1 it should be 5 V when no triggering occurs if it is not then

replace the transistor.

Step VI : Now if the cutter Led is not glowing while switching then check the

polarity of the LED again, still it is not glowing then check the LED using DMM.

Then follow the step 3 again for opto-coupler.

Step VII : The voltage across the capacitors must be equal to + 5V. If it is not

then it means the capacitor is sinking a current hence it is weak need to replace

it.

So here in this chapter we have seen different units of entire system hardware

with discrete functionality. The functionality of the hardware should be same as

described, if it is not then refer the trouble shooting for each circuit. The

initializations of these unit through the software routines and the flow charts are

given in the next chapter.



System flowcharts

Introduction to µVision 3 Keil Software

The microcontroller device programmer

Smart ICP 1.2 – The Programmer software

Testing result

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3.1

SYSTEM FLOWCHARTS :

3.1.1 Flowchart representing the working of the system :

INITIALIZATION OF MICROCONTROLLER AND SYSTEM PERIPHERALS

( PORT PINS,LCD,CCU ,RTC ,KEYBOARD )

READ THE PARAMETERS FROM THE EEPROM AND ASSIGN TEMPORARY VARIABLES

( PREVIOUSLY RUNNING PARAMETERS )

DISPLAY WELCOME MESSAGES

RUN MODE – DISPLAY LENGTH AND FREQUENCY, CALCULATE THE PULSE COUNT FROM TEMPORARY

VARIABLES, WRITE THEM AGAIN TO THE EEPROM

IF KEY IS PRESSED

?

KEY DEBOUNCE DELAY

IDENTIFY THE KEY, TAKE CORRESPONDING ACTION AND DISPLAY THE SAME THROUGH LCD

SET THE REQUIRED PARAMETERS THROUGH KEYBOARD

END

START

YES

NO



3.1.2 Flowchart for LCD initialization :



3.1.3 Flowchart for CCU initialization :

START

CHECK THE VALUE OF VARIABLE ‘ freq’WHICH CONTAINS OUTPUT FREQUENCY

(1 TO 70 kHz , PREVIOUSLY RUNNING FREQUENCY)

DISABLE ALL CAPTURE COMPARE CHANNEL EXCEPT ‘A’

ENABLE OUTPUT COMPARE CHANNEL ‘A’ INTERRUPT

LOAD HALF VALUE OF TIMER OVERFLOW RELOAD REGISTERS

TO OUTPUT COMPARE REGISTERS ‘OCRAH, OCARL’

SET CHANNEL ’ A’ TO NON INVERTING SYMMETRICAL ‘PWM’ MODE

LOAD PREDEFINED VALUE TO TIMER OVERFLOW RELOAD REGISTERS ‘TOR2H, TOR2L’

AS PER THE VALUE OF VARIABLE ‘freq’

END OF INITIALIZATION



3.1.4 Flowchart for RTC initialization :

START

SET RELOAD VALUE TO RTC TIMERS (AS DERIVED IN SECTION 2.3.4)

SELECT CCU CLOCK AS A RTC CLOCK SOURCEAND

ENABLE RTC UNIT

ENABLE WATCH DOG / RTC INTERRUPT


3.1.5 Flowchart for Keyboard initialization :

START

SET ALL PORT PINS HIGH OF PORT P0 EXCEPT P0.6

ALLOW P0.1,P0.2,P0.3 PINS TO GENERATE KEYBOARD INTERRUPT USING ‘KBMASK’ REGISTER’

SET THE INPUT PATTERN THAT SHOULD NOT BE ALLOWED USING ‘KBPATN’ REGISTER

ENABLE KEYBOARD INTERRUPT




3.1.6 Flowcharts for Interrupt Service Routines : 3.1.6.1 External Hardware interrupt 0 – Stop Proximity Switch ISR :

ON SENSING THE NEGATIVE LEVEL ON PIN P1.3 (EXT0)THE INTERRUPT ROUTINE IS EXECUTED FOR STOP PROXIMITY SWITCH

DISABLE ALL EXTERNAL INTERRUPT TEMPORARYDISABLE KEYBOARD INTERRUPT TEMPORARY

DISABLE WATCHDOG/ RTC INTERRUPT TEMPOARARY

CLEAR PIN P2.5 PULSE LED STATUS PINCLEAR PIN P2.7 CUTTER ON/OFF PIN – STOP CUTTER ASSEMBLY

SET HLTRN BIT OF REGISTER TCR20 TO FORCE AN IMMEDIATE HALTED PWM OF CCU

STORE CURRENT VALUE OF CCU TIMERS TEMPORARYAND STOP CCU TIMERS

STORE CURRENT VALUE OF ACTUAL PULSE COUNT VALUE TEMPORARY

SET THE ‘ tstop’ VARIABLE AS AN INDICATION OF STOP PROXIMITY SWITCH HAS SENSED

DISPLAY FAILURE MESSAGEENABLE EXTERNAL INTERRUPTS

END OF INTERRUPT SERVICE ROUTINE FOR STOP PROXIMITY SWITCH

START PROXIMITY SWITCH HAS SENSED

?

NO

YES



3.1.6.2 External Hardware interrupt 1 – Start Proximity Switch ISR :

ON SENSING THE NEGATIVE GOING PULSE ON PIN P1.4 (EXT1)THE INTERRUPT ROUTINE IS EXECUTED FOR START PROXIMITY SWITCH

IS ‘ctrl’ TEMPORARY BIT

SET?

IS ‘tstop’ TEMPORARY BIT

SET?

ENABLE WATCHDOG/ RTC INTERRUPT

LOAD TEMPORARY STORED VALUE ( WHILE STOP PROXIMITY ISR)

OF CCU TIMERS

LOAD TEMPORARY STORED VALUE ( WHILE STOP PROXIMITY ISR)

OF ACTUAL PULSE COUNT

DISPLAY LENGTH AND RUNNING CONDITION AGAIN

CLEAR THE ‘tstop’ BIT

DISABLE EXTERNAL INTERRUPT 1DISABLE KEYBOARD INTERRUPT

YES

NO

YES

ANO

B



B

ENABLE OUTPUT COMPARE CHANNEL A ( OCA )

SET ‘ccu_flag’ VARIABLE AS A BEGINNING OF CCU OPERATION

SET THE ‘pulsled’ AS AN INDICATION OF START OF PULSE TRAIN

CLEAR ‘HLTRN’ BIT OF ‘TCR20' RGISTER OF CCU TO RESTART PWM

ENABLE CCU INTERRUPT

START CCU TIMERS

END OF INTERRUPT SERVICE ROUTINE FORSTART PROXIMITY SWITCH

A



3.1.6.3 Software interrupt – Real Time Clock ( RTC ) ISR :

ON SETTING WATCHDOG/ RTC INTERRUPT BITTHE RTC ISR IS EXECUTED

IS INTERRUPT CAUSED BY RTC

?

IS INTERRUPT CAUSED BY

WATCHDOG TIMER?

CLEAR WATCHDOG TIMER INTERRUPT FLAG

CLEAR ‘pulsled’ AS AN INDICATION OF PULSE TRAIN IS OVER

SET ‘cutter’ AS SWITCHING ON CUTTER ASSEMBLY

THROUGH RELAY

DISABLE EXTERNAL INTERRUPT 1

INCREMENT ‘rtccnt’ BY ONE AS APPROACHING TOTAL ON TIME DURATION

FOR CUTTER ASSEMBLY

CLEAR RTC INTERRUPT FLAG

IS rtccnt < time

?

NO

C

D

NO

YES

YES

NO

YES



C

STOP RTC TIMER

CLEAR P2.7 CUTTER ON/OFF PIN- STOP CUTTER ASSEMBLY

CLEAR ‘rtccnt’ AS CUTTER ON DURATION IS OVER

CLEAR ‘ccu_flag’ AND CLEAR ‘cnt_flag’ AS THE OPERATION IS OVER

ENABLE EXTERNAL INTERRUPTS ENABLE KEYBOARD INTYERRUPT

END OF INTERRUPT SERVICE ROUTINE FORRTC AS A CUTTER ASSEMBLY ON DURATION

D



3.1.6.4 Software interrupt – Key Board ISR :

ON PRESSING ANY KEY OF THE KEYBOARD THE KEYBOARD INTERRUPT FLAG BIT IS SET AND THE KEYBOARD INTERRUPT ROUTINE IS

EXECUTED

DISABLE KEYBOARD INTERRUPT TEMPORARY

DEBOUNCE DELAY OF 30 msec

FIND THE ROW AND COLUMN BY OBSERVING THE STATUS OF PORT 0 PINS

IF P0.1= 0THEN ROW=0

IF P0.2=0THEN ROW=1

IF P0.3=0THEN ROW=2

IS P0.4=0AND

P0.5=1?

COLUMN=0

COLUMN=1

DELAY FOR 2 msec

SET ‘flag’ VARIABLE BIT

YES

NO

RESET KEYBOARD INTERRUPT FLAG

END OF INTERRUPT SERVICE ROUTINE FOR KEYBOARD INTERRUPT



3.1.5.5 Software interrupt – CCU ISR :

ON EVERY COMPARE EVENT OF CCU TIMER THE CCU TIMER INTERRUPT FLAG IS SET AND THE CCU INTERRUPT ROUTINE IS EXECUTED

DISABLE CCU TIMER INTERRUPT FLAG

CLEAR CARRY FLAG OF PROGRAM STATUS WORD

CLEAR THE ACCUMULATOR ‘A’

INCREMENT THE ACCUMULATOR BY ONE

IS ‘A’ < ACTUAL PULSE COUNT

?

STOP THE CCU TIMER

DISABLE CCU INTERRUPT FLAG

DISABLE OUTPUT COMPARE CHANNEL ‘A’

SET THE ‘cnt_flag’ FOR RESUMING THE RTC TIMER AT THE END

END OF INTERRUPT SERVICE ROUTINEFOR CCU INTERRUPT

YES

NO



3.2

3.2.1 What is µVision3 ?

INTRODUCTION TO µVISION3 KEIL SOFTWARE :

Keil micro vision is an integrated development environment used to create

software to be run on embedded systems ( like a microcontroller). It allows for

such software to be written either in assembly or C programming languages and

for that software to be simulated on a computer before being loaded onto the

microcontroller.

µVision3 is an IDE ( Integrated Development Environment) which is a window

based software development platform that combines a robust editor, project

manager and make facility. µVision3 integrates all tools including the C compiler

, macro assembler, linker/locator, and a hex file generator. µVision3 helps

expedite the development process of your embedded applications by providing the

following:

Full-featured source code editor

Device database for configuring the development tool setting

Project manager for creating and maintaining projects

Integrated make facility for assembling, compiling and linking your embedded

applications

Dialogs for all development toll settings

True integrated source level debugger with high speed CPU and peripheral

simulator

Advanced GDI interface for software debugging in the target hardware and for

connection to Keil ULINK

Flash programming utility fro downloading the application program into flash

ROM



3.2.2 Step followed in creating an application in µVision3 : To create a new project in µVision3

1. Select project new project

2. select a directory and enter the name of the project file.

3. Select project Select device and select a device from Device database.

4. create source files to add to the projects.

5. Select project Targets, groups , and files. Add/Files, select source

group1, and add the source files to the project.

6. Select project options and set the toll options. Note that when the target

device is selected form the device database all special options are set

automatically. Default memory model settings are optimal for most

applications.

7. Select project- rebuild all target files or build target

To create a new project, simply start Micro vision and select “ Project” “ New

Project” from the pull-down menus. In the file dialog that appears, choose a name

and base directory for the project. It is recommended that a new directory be

created for each project, as several files will be generated. Once the project has

been named, the dialog shown in the figure below will appear, prompting the user

to select a target device. In this lab, the chip being used is the “ P89LPC932A1”,

which is listed under the heading “NXP ( founded by Philips)”. This procedure for

selecting a device is shown in the following figure.



Figure 3.1(a) Selecting a Device Vendor Name

Figure 3.1 (b) Selecting a Device Figure 3.1 Widows For Selecting Target Device



Next , µVision3 must be instructed to generate a HEX file upon a program

compilation. A HEX file is a standard file format for storing executable code that

is to be loaded onto the microcontroller.

In the “Project Workspace” pane at the left, right click on “Target 1” and select “

options for ‘ Target 1’. Under the “Output” tab of the resulting options dialog,

ensure that both “ Create Executable” and “ Create HEX file” options are

checked. Then click “OK” as shown in figure below.

Figure 3.2 Project Option Dialog Window

Next a file must be added to the project that will contain the project code. To do

this, expand “Target 1” heading, right click on the “Source Group1” folder, and

select “Add files…” Create a new blank file ( the file name should end in “.asm”

or “.C ” ), select it, and click “Add”. The new file should now appear in the



“Project Workspace” pane under the “Source Group1” folder. Double click on the

newly created file to open it in the editor. All code fro this lab will go in this file.

To compile the program, first save all source files by clicking “Save All” button,

and then click on the “Rebuild All Target Files” to compile the programs as

shown on the figure below. If any errors or warnings occur during compilation,

they will be displayed in the output window at the bottom screen. All errors and

warning will reference the line and column number in which they occur along

with a description of the problem so that they can be easily located. Note that

only errors indicate that the compilation failed, warnings do not ( though it is

generally a good idea to look into them anyway).

Figure 3.3 “ Save all” And “ Build All Target Files” Options

When the program has been successfully compiled, it can be simulated using the

integrated debugger in Keil µVision3. To start the debugger, select “ Debug”

“Start/ Stop Debug Session” from the pull down menus.

At the left side of the debugger window, a table is displayed containing several

key parameters about the simulated microcontroller, most notably the elapsed

time ( circled in the figure below). Just above that , these are several buttons that

control code execution. The “Run” button will cause the program to run

continuously until a breakpoint is reached, whereas the “Step Into” button will

execute the next line of code and then pause (the current position in the program

is indicated by a yellow arrow to the left of the code).



Figure 3.4 µvison3 Debugger Window

Breakpoints can be set by double–clicking on the grey bar on the left edge of the

window containing the program code. A breakpoint is indicated by a red box next

to the line of code.

The current state of the pins on each I/O port on the simulated microcontroller can

also be displayed. To view the state of a port, select “Peripherals” “I/O Ports”

“Port n” from the pull–down menus, where n is the port number. A checked

box in the port window indicates a high (1) pin, and an empty box indicates a low

(0) pin. Both the I/O port data and the data at the left side of the screen are

updated whenever the program is paused.



Figure 3.5 ‘Reset’, ‘Run’ and ‘Step into’ options for Debugging Window

The debugger will help eliminate many programming errors, however the

simulation is not perfect and code that executes properly in simulation may not

always work on the actual microcontroller.



3.2.3 Device Database

A unique feature of the Keil µVision3 IDE is the Device Database, which

contains information about more than 400 supported microcontrollers. When you

create a new µVision3 project and select the target chip from the database,

µVision3 sets all assembler, compiler, linker, and debugger options for you. The

only option you must configure is the memory map.

3.2.4 Peripheral Simulation

The µVision3 Debugger provides complete simulation for the CPU and on-chip

peripherals of most embedded devices. To discover which peripherals of a device

are supported, in µVision3 select the Simulated Peripherals item from the Help

menu. You may also use the web-based Device Database. We are constantly

adding new devices and simulation support for on-chip peripherals so be sure to

check Device Database often.

3.3 THE MICROCONTROLLER DEVICE PROGRAMMER

The programmer used is a powerful programmer for the Philips NXP 89C51

series of microcontrollers that includes P89LPC 9XX, P89V51RXX,

P89CV51RXX ,P89LV51RXX, P89V52X2,LPC2000 and all the NXP controllers

which have the facility of ICP or ISP programming.

It is simple to use & low cost, yet powerful flash microcontroller programmer for

the NXP 89C51 series. It will Program, Read and Verify Code Data, Write Lock

Bits, Erase and Blank Check. All fuse and lock bits are programmable. This

programmer has intelligent onboard firmware and connects to the USB port. It can

be used with any type of computer and requires a special hardware. All that is

needed is a USB communication port which all computers have.



All devices also have a number of lock bits to provide various levels of software

and programming protection. These lock bits are fully programmable using this

programmer. Lock bits are useful to protect the program to be read back from

microcontroller only allowing erase to reprogram the microcontroller.

Major parts of this programmer are USB port, Power Supply, and a special

hardware Board provided with the Firmware.

All the programming ‘intelligence’ is built into the programmer and all the data is

sent or received through the USB. Programmer comes with window based

software for easy programming of the devices.

Figure 3.6 The Smart ISP Programmer



3.4

• For the programming the microcontroller , first discard all the connections

of the main board including the supply itself.

SMART ICP 1. 2 – THE PROGRAMMER SOFTWARE

‘Smart ICP 1.2’ is a software working as a user friendly interface for programmer

board from ‘Potent embedded solutions’. ‘Smart ICP 1.2’ gets its name from

“Program Loader” term, because that is what it is supposed to do. It takes in

compiled HEX file and loads it to the hardware.

Any compiler can be used with it, Assembly or C, as all of them generate

compiled HEX files. ‘Smart ICP 1.2’ accepts the Intel HEX format file generated

from compiler to be sent to target microcontroller. It auto detects the hardware

connected to the USB port. It also auto detects the chip inserted and bytes used.

The software requires no overhead of any external DLL.

The programmer connects to the computer’s USB port with a standard USB to

mini USB cable. No PC Card Required.

After making the necessary selections, the ‘Program’ button is clicked as shown

in the figure below which burns the selected hex file onto the microcontroller.

Steps for programming :

• Now the three pin connector ( Reset, Vdd , GND ) from the programmer

hardware is to be connected to the programming port 2 as shown in the

figure 2.18, and the two pin connector ( PCA , PCD) to the programming

port 1 ( as shown in the figure 2.18 )

• Now connect the USB cable from the programmer Board to the USB port

of the PC.



• Open the ‘Smart ICP 1.2’ software window and click on the search device

button two or more times. It will automatically identify the controller

Device

Figure 3.7 ICP Programming Window

• Now click on the ‘select hex file’ button, browse the hex file to upload ,

and click download button .



Figure 3.8 device select window with hex file

• Now click on the ‘ update configuration’ button and then click on the ‘start

programming’ button.

• The programmer will automatically erase and blank Checks the flash

memory and verify code data, write Lock Bits. After getting “Verify Ok”

, disconnect the board from the USB also discard the connectors, re-

assemble the main board.

• Now the micro controller is programmed perfectly and ready to run the

system hardware.



Figure 3.9 Device Programming Window

So, the above steps are very helpful for programming the microcontroller device.

For that you do not need to detach the microcontroller from the system board, just

simply connecting the two connectors and using the above software tool we can

easily program the microcontroller.



3.5

Let,

Servo parameter multiplier : 0

TESTING RESULT :

1

Precision pulses (bits) in terms of 2^ X : 1 1 ( as per standard value )

Feed roller diameter : 0 0 8 0 mm

Required Length of the sheet : 0 2 5 1 mm

Offset length : 3 2 7 2 um

Gear ratio : 0 1

So, displacement length of the feed roller

DLR = 3.14159 x 80 / 0 1

= 251.3272 mm

Calculation for servo parameters

ANS = 2 x 2^ 11 / 0 1

= 4096

Actual length = 0 2 5 1 (mm) + 3 7 2 7 (um)

= 251.3272 mm

So Actual Pulse Count = 251.3272 x 4096 / 251.3272

= 4096

RESULT:

On sensing the start proximity switch the pulse train is generated and fed to the

servo drive. The drive is connected to motor and motor shaft is directly connected

to the feed roller, which completes exact one rotation

Here the pulse frequency only decides rotation speed; higher the frequency ,

higher the speed towards completing the task.

for desired length

independent of the pulse frequency.



So, in this chapter we come to know about the flowcharts of different units as a

consequence of developing the software routines. Also we come to know about a

very powerful software developing tool Keil µvision3. Also we have the testing

result which tells , how the precise system has been built.



Hardware installation manual

Pulse position mode setup for servo drive

Setting common basic functions for servo drive

Display layouts with parameter feeding

Final prototype

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4.1 First of all we are going to see the hardware installation for the unit. The following figure

shows the actual hardware connection.

HARDWARE INSTALLATION MANUAL :

Figure 4.1 System Connection To Peripherals



As connection done as shown in the above figure now go through following steps.

The following steps are mandatory:

Step I: The pin connections are to be made very carefully for CN1 as given in

the following section.

Step-II : Check all the connections very carefully.

Step-III : Do not connect the servo motor directly to the belt assembly without

testing.

Step-IV : Switch on the power supply of C2L first, and wait till the welcome

messages are over.

Step-V : Now switch on the power supply of servo drive.

Step-VI: Set the parameters for pulse position mode for the servo drive as given

in the following section.

Step-VII: On completing step-V switch off the drive supply and again switch on

the drive supply.

Step-VIII : Feed the parameters through the keyboard as given in section 3.5

Testing Result. If you are getting the same result by feeding those parameters then

the motor can be now connected to the belt assembly.

Note: In case of switching off the entire unit, first of all switch off the servo

assembly first and then & then switch off the C2L unit.



4.2

Setting Parameters:

Set the following parameters for position control using pulse train.

PULSE POSITION MODE SETUP FOR SERVO DRIVE :

1) Control Mode selection

2) Setting a reference Pulse Form

Set the input form for the SERVOPACK using parameter Pn2000.0 according to

the host controller specifications.



3) Clear signal Form Selection

The internal processing of the SERVOPACK for the clear signal can be set to

either of four types by parameter Pn200.1. Select according to the specifications

of the machines or host controller.



4) Clear Operation Selection

This parameter determines when the error pulse should be cleared according to

the condition of the SERVOPACK, in addition to the clearing operation of the

clear signal(CLR). Either of three clearing modes can be selected with Pn200.2.



4.3 SETTING COMMON BASIC FUNCTIONS FOR SERVO DRIVE

1) Servo ON signal (/S ON)

4.3.1 Setting the ON Signal

This sets the servo ON signal (/S ON) that determines whether the servomotor

power is ON or OFF.

2) Enabling/Disabling the Servo ON signal

A parameter can be always used to set a parameter servo ON. This eliminates the

need to write /S-ON, but care must be taken because the SERVOPACK can

operate as soon as the power is turned ON.



4.3.2 Switching the servomotor Rotation Direction The rotation of direction of the servo motor can be switched without changing the

reference pulse to the SERVOPACK or the reference voltage polarity.

This cause the travel direction(+,-) of the shaft reverse. The output signal polarity

such as encoder pulse output and analog monitor signal from the SERVOPACK

does not change.

The standard setting for ”forward rotation” is counterclockwise as viewed from

the drive end.



4.4 DISPLAY LAYOUTS WITH PARAMETER FEEDING :

figure 4.2 ‘C2L- Cut To Length Controller’

Now we’ll see different layouts of and handling of the parameters using keyboard

As we switch on the supply for the system, u can see the welcome messages

through the LCD. After that the running mode will be displayed.

Display Layout 1:



Display Layout 2:

Display Layout 3:

Display Layout 4:



Display Layout 5:

Display Layout 6 :

Display Layout 7:

Now again pressing the enter key , it comes to the display layout1 by recalculating

the desired count and rewriting all parameters to the EEPROM again.



4.5 FINAL PROTOTYPE

Figure 4.3 Final Prototype



CONCLUSION

A step by step approach in designing the microcontroller based system for cutting

the desired length of the sheet and control for essential parameters for SERVO

PACK and belt assembly. The result obtained from the calculation have shown

that the system performance is quite reliable and accurate.

The system has successfully overcome quite a few shortcomings of the existing

systems by reducing the power consumption, maintenance and complexity, at the

same time providing a flexible and precise form of maintaining the requirement.

The continuously decreasing costs of hardware and software, the wider

acceptance of electronic systems in Industry, and an emerging Automation control

system in several areas, will result in reliable control systems that will address

several aspects of quality and quantity of production. Further improvement will be

made as less expensive and more reliable sensors are developed for Automation.

Although the enhancements for the system, the required technology and

components are available, many much systems have been independently

developed, or are at least tested at a prototype level. Also, integration of all these

technologies is not a daunting task and can be successfully carried out.



FUTURE SCOPE

The performance of the system can be further improved in terms of the operating

speed, memory capacity, instruction cycle period of the microcontroller by using

other advanced microcontrollers.

The device can be made to perform better by providing the power supply with the

help of battery source which can be rechargeable or solar powered, to reduce the

requirement of main AC power.

A multi controller system can be developed that will enable a master controller

along with its slave controllers to automate multiple conveyor belt assembly

simultaneously.

With further modifications for the software and hardware we can automate the

multi dimensional cutting with higher precision without the need of MP machine

controller. The same system can be used in metal industry for metal sheet cutting

with the further modifications.



REFERENCES White Papers

[1] Ludovico Alcorta, ‘the impact of industrial Automation On Industrial

Organization: Implications fro developing Countries Competitiveness’; The

United Nations University ,INTECH Institute for New Technologies, discussion

paper series # 9508.

[2] Turnell, D.J de Fatime, Q.V., G.S. Freire, An integrated, modular industrial

automation system, Proceedings of IEEE International Conference On Systems,

Man, and Cybernetics, Vol.2 , Oct 1998.

Books

[1] Muhammad Ali Mazidi, Janice Gillispie Mazidi, ROlin D. MC Knlay, The 8051

Microcontroller & Embedded Systems, Pearson Education Inc. 2nd Edition, 2008.

[2] Myke Predko,Programming & Customizing the 8051 Microcontroller,TMH,1999.

[3] Ramakant Gayakwad, Operational Ampilfiers Linear Integrated Circuits, Prentice

Hall of India , 3rd Edition.

[4] E Balagurusamy, Programming in ANSI C , TMH, 3rd

[1] http: //

Edition,2004.

Web sources

www.electro-tech-online.com

[2] http:// www.Globalspec.com

http://www.electro-tech-online.com/

http://www.globalspec.com/



[3] http:// www.8052.com

[4] http:// www.8051projects.net/forum

[5] http:// www.datasheetdirect.com

[6] http:// www.keil.com/appnotes

[7] http:// www.fargocontrols.com

[8] http:// www.pc-control.co.uk

[9] http:// www.wisegeek.com

http://www.8052.com/

http://www.8051projects.net/forum

http://www.datasheetdirect.com/

http://www.keil.com/appnotes

http://www.fargocontrols.com/

http://www.pc-control.co.uk/

http://www.wisegeek.com/



ANNEXURE-I



















































ANNEXURE-II







Final Report on Cut to length controller using P89LPC932

Documents

Final Report on Cut to length controller using P89LPC932