Low Cost Kiosk Touchscreen

8/3/2019 Low Cost Kiosk Touchscreen

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INTRODUCTION

In the last decade, touch screen equipped displays have become common features in

applications ranging from kiosks, point of sale systems, industrial control, and medical

instrumentation. There are more choices in touch screen technologies and branded manufacturers

than ever. Paradoxically, the more choices that exist, the harder it is to ensure that the best touch

screen technology for your application has been selected.

The aim of the project is to build an ultralow cost touch screen kiosk for rural areas.

Booths can be setup by the local village authorities for awareness of the people. A specially

designed application running at the kiosks will allow the user to interface the touch screen.

Unlike conventional touch screens which either replace/replicate mouse, this touch screen will

provide very restricted access to the system.

A centralized system will be provided that would assist the administrator in creating,

compiling and uploading presentations for individual kiosks over internet. These presentations

can be identified by their respective URLs. Each kiosk will check and download the updated

presentations from internet at regular intervals. Each kiosk is given a unique URL to download its

presentation from internet. An application will be designed to run at kiosks that will take care of

downloading the presentations in the background whereas keep displaying presentations in the

front end. The application will also take input from touch screen and process presentation

accordingly.

An application will be designed for administrator to create, compile and upload

presentation. It will provide the administrator with image processing tools, text editing tools,

drawing tools, image scaling tools, etc. to create presentations. The software will also allow the

user to create regional language presentations. These would assist even a novice user to interface

the touch screen. Village specific presentations would allow the administrator to create

presentations with specific regional information, area wise awareness, information on healtheducation programs being held in that region, etc. Information regarding farming, medical

treatments, hygiene, AIDS, etc. can be displayed for awareness of the masses. Education and

teaching help can be provided for children (Animated Story Books & Alphabets, etc.).

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KIOSK:

Kiosk systems are small, freestanding enclosures that are usually designed to provide

information or services to consumers. Typically, kiosk design entails having an open side of the

enclosure or a window cut out that transactions can be conducted.

Interactive kiosk which are computerized touch screen systems growing in popularity. In

general, an interactive kiosk consists of a physical structure that holds any necessary hardware,

such as a touch screen monitor, stereo speaker, a printer and a CPU.In addition, interactive kiosk

systems hold software applications that can store data, administer transaction, exchange messages

or dispense products to consumers.

There is a continuing trend to develop terminals to deliver information and services to the

general public, accessible in public locations. These terminals, or kiosks, can deliver services at

the point of need and at low cost. The information contained within a stand-alone kiosk can be

updated at regular intervals via CD Rom. If the kiosks are networked, information can be

transmitted electronically to many sites rapidly to update the database or provide on-line user

access.

Kiosk may have been given introductory information on it beforehand, but the system

must also appear simple and intuitive if they are to start using it. The general public will include

people with very different levels of skill, experience and confidence in using interactive

computer-based systems. Therefore to be inclusive, kiosks must be designed to cater for thosewith limited skills or experience, physical and cognitive impairments, and should be supportive

towards those who are inhibited in interacting with them in a public area. This also means that

kiosk systems should be as self explanatory as possible.

We are designing touch screen for our project. A key benefit of touch technology is that

touch is intuitive and instantaneous. The process is simple, in that a set of instructions is followed

by just pointing and touching the screen; there is no complicated tool bar or function keys.

From a commercial viewpoint, touch screens make technology easy-to-use and accessible

to all and can significantly reduce the hours and cost involved in training employees. It also

enables much faster access to information as touch technology simplifies and speeds up the

process.

APPLICATION

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Indoor/outdoor kiosks.

ATMs.

Ticketing machines.

Medical instrumentation.

Process control systems.

Hospital operating rooms.

Commercial transportation.

Commercial food preparation and service.

Large plasma displays.

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LITERATURE SURVEY

Twenty years ago, cathode ray tubes (CRTs) were practically the only choice from which

to view highly graphical information content. CRTs were used for mainframe and mid-frame

terminals in emerging PC workstations; and embedded applications including cash registers,

avionics, medical instrumentation, industrial controls, and medical diagnostics.

The promise of increased productivity through computer automation was limited because

specialized training was required of workers to facilitate computer use. Only specialized

vocational users knew the arcane commands of UNIX, DOS, and machine computer commands.

Product designers sought a means of making their applications intuitive so that users would not

have to be trained in computer use. Combining the CRT, graphical user interface (GUI), and

touchscreen delivered an intuitive means of accessing the power of computer based applications.

The ubiquitous CRT mandated that early touch screen designs had to accommodate the curved

face of the CRT. The viewing area of a cathode ray tube can be molded in one of 3 ways:

spherical, cylindrical and flat screen. Flat screen CRTs were size and cost prohibitive for

mainstream applications, so spherical and cylindrical touch screen form factors became the most

widespread options.

Touchscreen designs for CRTs were based upon three technical approaches:

1. Resistive, capacitive, and acoustic technologies utilizing a direct sensor overlay affixed to a

curved glass plate that conformed to the curved glass surface of the CRT, similar to the

manner that a contact lens conforms to the shape of an eye.

2. Infrared (IR) LED based sensors affixed to the perimeter of the active area of the CRT

(sensors embedded within the bezel and directed across the face of the curved CRT surface).

3. Strain gauges that measured changes in deflection or balance of the CRT. (Strain gauge

sensors mounted inside the CRT enclosure or inside a pizza-box-shaped platform that

supported the CRT).

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PRESENT THEORY AND PRACTICES

PRESENT SCENARIO:

A low cost touch screen kiosk is basically a public information provider. Kiosk systems

are small, freestanding enclosures that are usually designed to provide information or services to

consumers. Typically, kiosk design entails having an open side of the enclosure or a window cut

out that transactions can be conducted.

Today personal computer have become need for everyone, it is no more luxury for the

people living in metros. Also, it has been a high time for people living in rural areas get access to

personal computer & internet so that they are not left behind. The need for computers & internet

is established however the cost of computer, software, internet, maintenance & upgrade is still

not affordable to many.

Information poverty is a widespread social problem throughout developing countries. The

rural internet kiosk can provide the following solutions: e-commerce, e-learning, relief service,

skills training, employment opportunities. India is a country with a wide variety in almost in

every field-ranging from food, clothing, language, religion, festivals, to a great divide in

academic & socio-economic background.

Information kiosks are being popularised both for delivering goverment services & for

socio-economic development of rural areas. Delivering relevant knowledge & services in local

languages is the promise of village kiosks in India. So we have decided to work on making touch

screen kiosk for rural area.

EXISTING SYSTEM:

Touch screens best suit applications that require frequent interaction with non-technical

users or must work in dirty environments. The devices are easy to use and can tolerate dirt and

moisture that would quickly disable a keyboard or a mouse. Some Touch screens can work

through a 2-inch thick barrier. This feature can protect both the system from user abuse and the

user from the systems environment. Compact designs can also benefit from touch screen

technology. Because Touch screens are integral to the display device, the screens eliminate the

need for a separate keypad. You can make hand-held devices with Touch screens as small as the

display itself. Touch screen technology comprises a variety of options that let you match the

technology to your application. For example, a touch screens sensor uses one of five

mechanisms; resistance, capacitance, acoustics, optics, and mechanical force.

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Types of Touch Screens:

1. Capacitive Type

2. Resistive Type

3. Surface acoustic wave

4. Infrared

Table No.1 Touch screen Market Adoptions The Early Years

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Design Approach Inherent Advantage Inherent Disadvantage Market Acceptance

Direct SensorOverlay (contact

lens)

Packaging advantage, touchzone accuracy.

Display image clarity andcontrast reduction.

Winner!

IR No reduction in display clarity. Cost of LEDS. X & Y axis touch

resolution is proportional to the

number of LEDs Parallax caused

by curvature in CRT face

lessened touch accuracy.

Loser

Strain Gauge No reduction in display clarity. Mechanical approach tocalibration proved too unreliable.

Loser


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Table No. 2: CRT Era: Touchscreen Technology Comparison

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Design Approach Inherent Principal

Advantages

Inherent Principal Disadvantages Market Acceptance

4-wire resistive 1. Inexpensive to

manufacture, no glass

substrate required.

2. Actuated by gloved

hand, hard or soft

stylus, and finger.

3. Easily sealable.

4. Low power.

1. Wrinkle prone when bonded to

spherically curved surfaces.

2. Display image reduction; only

75-80% transmissibility.

3. ITO on polymer sheet degrades

after heavy use.

4. Screen becomes worn in

frequently touched areas

obscuring image, especially in

high ambient light conditions.

5. Polymer coversheet can be torn

or cut which disables sensor.

1. Very limited acceptance in

CRT applications.

2. Widely used in small

Monochrome.

3. LCD designs

(like a PDA).

5-wire resistive 1. Durable, precise

touch calibrationwithout drift.

2. Easily sealable for

wet applications.

3. Could bond to

curved glasssubstrate

without wrinkles.

4. Actuated by gloved

hand, hard or soft

stylus, and finger.

5. Will continue to

function even if

sensor is torn or cut.

1. Display image reduction; only

75-80% transmissibility.2. Plastic can be torn.

3. Screen becomes worn in

frequently touched areas

obscuring image.

4. Proprietary drivers common.

5. Curved glass design is

expensive to manufacture.

1.Market share leader,

particularly in point-of-saleapplications.


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Surface capacitive 1. Very good image clarity.

2. Hard glass surface is

resistant to vandalism.

3. Foreign objects on screen

(like food or mud) do not

trigger a touch because they

are not a path to ground.

1. Occasional re-calibration

required.

2. Conductive stylus required.

3. Changes in users skin

moisture, relative humidity, or

proximity to metal can create

cursor drift.

4. ITO on surface can create

reflection.

5. Curved glass design is

expensive to manufacture.

6. No gloved hand functionality.

1. Market share leader,

particularly in gaming.

SAW 1. Best image clarity.

2. All glass construction no

conductive films.

3. Precise touch calibration

without drift.

4. Actuated by gloved hand,

soft stylus, and finger.

5. Z axis sensing.

1. Foreign objects on screen

such as food, liquid, or mud will

create a touch event.

2. Difficult to seal edges of

screen to a bezel because the

gasket can interfere with

acoustic wave form.

3. Expensive to manufacture.

1. Widely adopted for

indoor use.


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PROBLEM STATEMENT

The aim of the project is to build an ultralow cost touch screen kiosk for rural areas.

Booths can be setup by the local village authorities for awareness of the people. A specially

designed application running at the kiosks will allow the user to interface the touch screen.

In this project we are using infrared touch screen technology. This touch technology is

best suited to applications such as ATMs. Infrared technology has no limitations in terms of

objects that can be used to touch the screen, so we are using infrared touch screen for our project.

In addition to the other relative to the capacitance, resistance, and surface acoustic wave

touch screen outside of the various advantages, compared with other infrared touch screen also

has the following salient features: First: Super anti-Light interference performance. Easy to

excellent special (EDU-Touch) infrared touch screen using the most advanced current

international fifth-generation infrared transmitter and receiver, and through unique settings, with

the most advanced communications using optical filter materials so that the product is greatly

increased resistance to light, so that the sun shone directly at the sun environment (100,000 lux)

of the normal work in light of anti-industry peers did better. Second: Super-fast response time.

Easy to excellent special (EDU-Touch) Infrared touch screen response speed of the 8.5ms,

compared with other infrared touch screen response industry has doubled the speed to make your

operation more quickly. Third: a longer life .Easy to excellent special (EDU-Touch) Infrared

touch screen life of more than 60,000,000 hits life. Fourth: versatility plus personalized designs.

Easy to excellent special (EDU-Touch) Infrared touch screen design is both versatile and also can

according to your needs "tailored" to make your use more convenient, beautiful, meet all your

kinds of individual needs and special use functions. Fifth: One of sealed waterproof .Easy to

excellent special (EDU-Touch) Infrared touch screen unique one-time fully sealed process, so

that touch-screen water level reached the IP65, you can rest assured in a variety of environments,

to make your operation more safe and worry.

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PROJECT OVERVIEW AND DESIGN

SPECIFICATIONS

Electrical Specifications:

Infrared LED (QED233):

= 940 nm

Chip material =GaAs with AlGaAs window

Medium Emission Angle, 40

High Output Power

Package material and color: Clear, untinted, plastic

Infrared Receiver (TSOP1738):

Photo detector & pre-amplifier in one package.

Internal filter for PCM frequency

Improved shielding against electrical field disturbance

TTL & CMOS compatibility

Low power consumption(50mW)

Microcontroller-ATMEGA16:

16K Bytes of In-System Programmable (ISP) Flash Memory

Endurance: Write/Erase Cycles: 10,000 Flash/100,000 EEPROM

4.5V to 5.5V Operating Range

32 Programmable I/O Lines

Two 8-bit Timer/Counters with Separate prescalers and Compare Modes.

One 16-bit Timer/Counter with Separate prescaler, Compare Mode, and Capture.

Programmable Serial USART

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Programmable Watchdog Timer with Separate On-chip Oscillator.

Serial Interface:

MAX 232:-

Operates from a single 5V power supply with 1.0uF charge pump capacitors

Operate up to 120kbit/s

Two drivers and two receiver

+/- 30v input levels

Low supply current 8mA typical

RS232:

It is the interface between DTE & DCE using serial binary data exchange.

SPECIFICATIONS:

Transmitted signal voltage levels:

Binary 0:+5 to 15 Vdc

Binary 1:-5 to 15 Vdc

Received voltage levels:

Binary 0:+3 to +13Vdc

Binary 1:-3 to 13Vdc

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BLOCK DIAGRAM:

Figure 1:Block diagram of low cost touch screen

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TOUCHSCREENMICRO-

CONTROLLER

COMPUTER

MAX 232


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Figure 2: Touch screen with panel

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WORKING

IR touchscreens have sensors mounted around the active area of the display. Unlike

other touch technologies, the IR array is not part of the display overlay. The display overlay isnot an active part of the touch system.

Provided one uses a glass window, the active area of the display cannot be marred by

wrinkles, tears or wear spots. Horizontal and vertical sensors mounted in the bezel emit and

receive IR light energy. Breaking the horizontal and vertical light paths provides a simple, all

digital grid that identifies the touch location.

The digital nature of the IR touchscreen makes it immune to drift, thereby eliminates the

need for re-calibration in the field. On the down side, the IR sensors are occasionally

susceptible to false touches caused by objects which break the IR light beam path, such as a

rain drop or fly landing atop the display and breaking the IR path. Software is improving to

reject raindrop touches.

IR overload from direct sunlight can also create false touches, but only in extremely

bright, direct light.

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Explanation of each Block:-

Touch screen:

A touch screen is an assembly that is mounted in front of a video display.

It is activated by touching, with a stylus or finger, the selected area on.

The display that indicates the desired function.

The touch screen or frame has an independent X-Y coordinate system that is calibrated to

the display matrix.

The X-Y coordinates of the position of the stylus are communicated to the host computer

causing the desired action.

Here we have used Infrared touch screen technology.

Infrared technology relies on the interruption of an IR light in front of the display screen.

The touch frame contains a row of IR LEDs & photo detector, each mounted on two

opposite sides to create grid of invisible infrared light.

When touching the screen one or more of the beams the pass are obstructed resulting in an

X & a Y coordinate being sent to the controller to indicate the exact touch point.

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How it Works.

Figure 3:Obstacle detection sensor

TSOP Based obstacle detection sensor module:

The TSOP-OBSD single is a general purpose proximity sensor. The module consists of an

IR emitter & TSOP receiver pair. The high precision TSO receiver always detects a signal of

fixed frequency. Due to this, errors due to false detection of ambient light are significantly

reduced.

The module consists of 555 IC, working in astable multivibrator configuration. The

output of TSOP is high whenever it receives a fixed frequency & low otherwise. The on-board

LED indicator helps user to check status of the sensor without using any additional hardware.

The power consumption of this module is low. It gives a digital output & false detection due to

ambient light is low.

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Microcontroller (ATMEGA16):

The ATmega16 is a low-power CMOS 8-bit microcontroller based on the AVR enhanced

RISC architecture. By executing powerful instructions in a single clock cycle, the ATmega16

achieves throughputs approaching 1 MIPS per MHz allowing the system designer to optimize

power consumption versus processing speed.

MAX 232:

This 16 pin IC is used to interface between the pc & the microcontroller, which is used for

serial communication. It converts TTL voltage level to CMOS level & vice-versa. It operate with

single 5v supply, operate up to 120 Kbit/s, two drivers & two receivers, 30-V input levels, low

supply current 8mA typically. The MAX232 is a dual driver/receiver that includes a capacitive

voltage generator to supply TIA/EIA-232-F voltage levels from a single 5-V supply. These

receivers have a typical threshold of 1.3 V, a typical hysteresis of 0.5 V, and can accept 30-V

inputs. Each driver converts TTL/CMOS input levels into TIA/EIA-232-F levels.

RS 232:

For serial communication there is need of baud rate that transmits data as bits per second,

so in our project we have set baud rate at 9600.Use of RS-232 cable for full duplex data

transmission.

RS-232 communication, a low level (-3V to -15V) is defined as a logic 1 & referred as

marking. Similarly, a high level (+3V to +15V) is defined as logic 0 & is referred as spacing.

Here we are using serial communication. For serial communication RS232 is used.

Design details of each block:

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Oscillator Circuit:-

Any Microcontroller requires circuitry that generates the clock pulses by which all

internal operations are synchronized.

Figure 4: Oscillator Circuit

In AT89S52 two pins viz. pin no. 18 & 19(XTAL1 & XTAL2) are provided for

connecting a resonant network to form an oscillator. A quartz crystal is used with ceramic

capacitors as shown in above circuit diagram. The range of the can be connected to the

microcontroller is 1MHz to 16 MHz. Different crystals are available such as the quartz Rochellesalts, and Tourmaline etc. We have preferred to use Quartz crystal because it is inexpensive and

readily available.

C1 and C2 are between 1pF to 40 pF. The capacitors C1, C2 are used for stable frequency

operation i.e. in the condition where there is high noise and humidity as in the case of factories.

Due to this oscillator frequency can alter, for the suppression or do we can say deletions of these

two capacitor are used for stable frequency.

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Reset Circuit:

The 89S52 uses an active high reset pin. The reset input must go high for two machine

cycles. When power is first applied and then sink low.We have used simple RC circuit, which

provide system voltage (Vcc) to the reset pin until the capacitor begins to charge. The time for

which the reset pin is kept high depends on the time constant of the reset circuit.

Recommended time=1ms

Rc time constant=10K*10f=100ms

Figure 5: Reset Circuit

The value of the capacitor used is calculated using following steps,The value of the resistor is assumed as 10K and the value of the capacitor is calculated

using following formula,

Capacitor Voltage during charging

Vc=Vcce(-t/RC)

And during discharging is

Vc=Vcc(1- e(-t/RC))

Reset:

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A reset can be considered be the ultimate interrupt because the program may not block the

action of voltage on the RST pin. This type of interrupt is often called non maskeable because no

combination of bits in any register can stop, or mask, the reset action Unlike other interrupt, the

PC is not stored for later program resumption; a reset is an absolute command to jump to program

address 0000h and commence running from there.

RS232

Most of the people think that RS232 is a type of cable or connector but this is

misunderstanding. RS232 is the name of serial communication standard. In this standard logic 1

is denoted by voltage range (-3v to -15v) and logic 0 is denoted by voltage range (+3v to +15v).

MAX 232:

MAX 232 is the name of IC which is used for TTL to RS232 or RS232 to TTL

conversion. To communicate serially between two devices, that devices must be TTL compatible.

TTL compatibility means TTL logic levels (logic 1/ logic 0) must be same for both the devices.

For example if you want to communicate between 8051 and PIC microcontroller, you need to

connect them as shown in following diagram.

LOGIC 1 = 5v LOGIC 1 = 5v


Figure 6: Communication between 8051 and PIC

Here you can see Rx and Tx of both controllers are cross connected directly. There is no

need to connect them through MAX232 (as they are TTL compatible means LOGIC 1 = 5v

LOGIC 0 = 0v these logic levels are same for both the controllers)

Now consider example, you want to connect 8051 with ARM (LPC 2138), you can not

connect these two controllers as shown below

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PIC

Rx

T

x

8051

TxRx


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LOGIC 1 = 5v LOGIC 1 = 3.3v


Figure 7: Communication between 8051 and ARM

As you can see TTL logic levels are different for these controllers (they are not TTL

compatible). So the connections shown above are incorrect.Correct way to connect these two

controllers is shown below,

TTL

5v RS232 3.3v

Standard

Figure 8: Communication between two controllers

As shown in above diagram, data sent by 8051 in TTL (5v) format is converted in to RS

232 standard by MAX232. Then MAX3232 converts data in RS232 standard in to TTL (3.3v)

format and vice versa.

MAX232 converts TTL of 5v in to RS232 standard or RS232 standard in to TTL of 5v.

Whereas MAX3232 converts TTL of 3.3v in to RS232 standard or RS232 standard in to TTL of

3.3v.

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8051R

x

T

x

ARM

Tx

Rx

Rx

MAX232

MAX

232

8051

Rx

Tx

ARM

TxRx

Rx

MAX

232

Other serial device with

on-board MAX232(RS232 out)

(PC, GSM, GPS, XBEE,

FP Module, etc)

Controller

R

xT

x


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Figure 9: Interfacing technique of controller with serial devices

Above diagram shows the interfacing technique of controller with other serial devices like

PC, GPS, GSM, XBEE, BLUETOOTH, FP module. These devices have RS232 out means these

devices give out data in RS 232 standard, so to connect microcontroller with these devices, you

need to convert data coming from other serial devices in RS232 standard in to TTL using MAX

232.

This is the reason why MAX232 is used while interfacing microcontroller with these

kinds of serial devices.

t o T X o f t h e M i c r o C o n t r o l l e r

C 3

1 0 M F D

C 11 0 M F D

t o T X o f t h e o t h e r s

C 41 0 M F D

t o R X o f t h e o t h e r s eV C C

t o R X o f t h e M i c r o C o n t r o l l e r

C 2

1 0 M F D

M A X 2 3 2

1

3

4

5

2

6

1 2

9

1 1

1 0

1 3

8

1 4

7

C 1 +

C 1 -

C 2 +

C 2 -

V +

V -

R 1 O U T

R 2 O U T

T 1 I N

T 2 I N

R 1 I N

R 2 I N

T 1 O U T

T 2 O U T

Figure 10: Circuit diagram for MAX232

Why to use external capacitors with MAX232?

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The capacitors used around MAX232 are called as Pumping capacitors. These are used

for level conversion (TTL to RS232 / RS232 to TTL).

The capacitor type used for C1C4 is not critical for proper operation. The MAX232E

and MAX241E require 1F capacitors, although in all cases capacitors up to 10F can be used

without harm. Ceramic, aluminum-electrolytic, or tantalum capacitors are suggested for the 1F

capacitors.

When using the minimum recommended capacitor values, make sure the capacitance

value does not degrade excessively as the operating temperature varies. If in doubt, use capacitors

with a larger (e.g., 2x) nominal value. The capacitors effective series resistance (ESR), which

usually rises at low temperatures, influences the amount of ripple on V+ and V-.

Use larger capacitors (up to 10F) to reduce the output impedance at V+ and V-. This can

be useful when stealing power from V+ or from V-.

LCD Display Interfacing

Most of the projects with the any processor/microcontroller CPU (8085/8051/AVR/ARM)

require some form of display. In market various displays are available like 7-segment, 5*7 matrix

LED and LCD, bar graph, LCD, etc. Its important for deciding the required display set for our

project. Selection of display depends on various factors like power consumption, ambient light

conditions, surrounding temperature, visibility from long distance, total information to be display,

cost of display, circuit/lines required for display interfacing, etc. The most common way to

accomplish this is with the LCD (Liquid Crystal Display). LCDs have become a cheap and easy

way to get text display for an embedded system.

Common LCD displays are set up as 16 to 20 characters by 1 to 4 lines and noted as 16*2,

20*2, 16*4, 20*4, etc. Following figure shows the basic pin diagram of 16*2 LCD display.

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Figure 11: Pin diagram of 16*2 LCD Display

Data pins D7-D0: Pins 7-14:

Bi-directional data/command pins. Alphanumeric characters are sent in ASCII format. As

shown in figure, there are 8 pins, Pin No.7-14 used for data lines.

RS: Register Select: Pin No.4:

RS = 0; Command Register is selected

RS = 1; Data Register is selected

R/W: Read or Write: Pin No.5:

R/W=0; Write.

R/W=1; Read

E: Enable (Latch data): Pin No.6:

Used to latch the data present on the data pins.

A high-to-low edge is needed to latch the data.

Vo: contrast control: Pin No.2:

LCD Commands:

The LCDs internal controller accepts several commands and modifies the display

accordingly. These commands would be things like:

Clear screen, Return home, Shift display right/left

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Table no. 3: L CD Co mm an ds

Instruction Decimal HEX

Function set (8-bit interface, 2 lines, 5*7 Pixels) 56 38

Function set (8-bit interface, 1 line, 5*7 Pixels) 48 30

Function set (4-bit interface, 2 lines, 5*7 Pixels) 40 28

Function set (4-bit interface, 1 line, 5*7 Pixels) 32 20

Entry mode set See Below See Below

Scroll display one character right (all lines) 28 1E

Scroll display one character left (all lines) 24 18

Home (move cursor to top/left character position) 2 2

Move cursor one character left 16 10

Move cursor one character right 20 14

Turn on visible underline cursor 14 0E

Turn on visible blinking-block cursor 15 0F

Make cursor invisible 12 0C

Blank the display (without clearing) 8 08

Restore the display (with cursor hidden) 12 0C

Clear Screen 1 01

Set cursor position (DDRAM address) 128 + addr 80+ addr

Set pointer in character-generator RAM (CG RAM address) 64 + addr 40+ addr

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CIRCUIT DIAGRAM:

Figure 12: Cir cui t dia gra m f or low cos t tou ch scr een

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PCB LAYOUT:

Figure 13: PCB layout of low cost touch screen

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SOFTWARE DESIGN

Programming language:

We have used VISUAL BASIC 6.0 as a programming language to construct our system.

Microsoft Visual Basic 6.0:

The power of visual basic 6.0 comes from the main source i.e simple & efficient way in

which one can program. Visual basic is an ideal programming language for developing

sophisticated applications for Microsoft Windows it makes use of graphical user interface for

creating powerful applications with graphics.

Visual basic provides you with a complete set of tools simplify rapid application

development. The Visual basic programming system, application edition include in MS Access &

many other applications.

A complete installation of most powerful version of Visual Basic 6.0 the enterprise

edition requires more than 250MB.

Features of Microsoft visual basic:

It is graphic user interface.

Easy to get program up & running quick.

Easy to learn.

Provide wizard to assist users.

Develop windows base applications, using & customizing toolbar, menu bar & shortcut

menus working with data.

FLOW CHART:

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NO

YES

NO

YES

FLOW CHART FOR VB MODULE:

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INITIALISE LCD, SERIAL PORT& CONTROLLER

SCAN FOR 5 COLUMNS

CHECK IF

ANY

COLUMN(IR) CUT

STORE THE STATUS &

SCAN FOR ROWS

CHECK

IF ANY

ROW (IR)CUT

STORE THE STATUS

TRANSMIT ROWS &COLUMNS

STOP


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NO

YES

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START

Form Load Event

Close COM

Port

Select, initialize &Open resp. COM

Port

Load Front Page

Wait For Serial

Event to Occur

If

Valid

Data

Load resp. Image


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FIGURE 14: PROJECT FLOW DIAGRAM

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HARDWARE TESTING:

Component testing:

1. Transformer testing:

For identifying the primary & secondary sides of transformer, we have measured the

resistance on two sides of transformer with the help of multi meter. The side which has large

resistance value is primary side & other is secondary.

2. Testing of resistor:

For checking the resistor values select the proper range on multi meter.

If the measured value is not within the limit then the resistor is faulty.

If the multi meter shows the infinite, then the resistor is not fixed

Properly .

If the multi meter shows the zero, then the resistor is shorted.

3. Testing of capacitors:

It is checked by using multi meters.

The capacitor shows zero value if it is leaky.

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Circuit testing:

1. TESTING OF MICRO CONTROLLER (89S52):

a) Voltage at pin 40 of micro controller= 5V

b) Frequency at pin 18 & 19=11.0592V

2. TESTING OF LCD DISPLAY (16*2):

a) Voltage at pin 2 of LCD= 5V

b) Using contrast pot at pin no. 3 we have observed contrast change.

3. TESTING OF MAX232:

a) The Vcc at pin no. 16=5V.

b) The current of MAX232=30mA.

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RESULTS

ADVANTAGES:

Best screen clarity as there is no overlay.

Even a novice user can interface with the system

Village specific presentations would allow the administrator to create presentations with

specific regional information

Touch screens can be used million times without losing performance.

IR touch screen kiosk can handle dusty and harsh conditions.

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APPLICATION:

1. Public Information Systems: Information kiosks, tourism displays, and other

electronic displays are used by many people that have little or no computing experience.

The user-friendly touchscreen interface can be less intimidating and easier to use than

other input devices, especially for novice users, making information accessible to the

widest possible audience.

2. Restaurant/POS Systems: Time is money, especially in a fast paced restaurant or

retail environment. Because touchscreen systems are easy to use, overall training time for

new employees can be reduced. And work can get done faster, because employees can

simply touch the screen to perform tasks, rather than entering complex key strokes or

commands.

3. Customer Self-Service: In today's fast pace world, waiting in line is one of the things

that has yet to speed up. Self-service touchscreen terminals can be used to improve

customer service at busy stores, fast service restaurants, transportation hubs, and more.

Customers can quickly place their own orders or check themselves in or out, saving them

time, and decreasing wait times for other customers.

4. Control/Automation Systems:The touchscreen interface is useful in systems

ranging from industrial process control to home automation. By integrating the input

device with the display, valuable workspace can be saved. And with a graphical interface,

operators can monitor and control complex operations in real-time by simply touching the

screen.

5. Computer Based Training: Because the touchscreen interface is more user-friendly

than other input devices, overall training time for computer novices, and therefore

training expense, can be reduced. It can also help to make learning more fun and

interactive, which can lead to a more beneficial training experience for both students and

educators.

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CONCLUSION

Twenty years ago, PCs were just arriving on the scene and simple GUI interfaces were

almost unheard of. Designers strove to use touchscreens to simplify computer input commandsfor largely unsophisticated computer users. The proliferation of touch-enabled self-service

kiosks, the conversion from cash registers to point of sale systems, and countless automotive,

medical, training, and industrial products that use touchscreens as operator interfaces have

validated the touchscreen concept.

Today, a larger share of our population is PC literate, yet the touchscreen has become

adopted by computer users of all abilities because it is simple, fast, and intuitive. Todays

product designer or system integrator would be served to remember yesterdays technology

adoption challenges and flexibly adopt new technological approaches if they wish to solve

todays application challenges. With the advances in LCDs, it is time to revisit the potential for

IR touch technology as an effective solution for bringing touch capabilities to the current

generation of computing devices.

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FUTURE SCOPE

1. In future we can use internet to update the presentations in kiosks.

2. IR technology can be adapted to enable multi-touch input.

3. Shrinking package size of IR LEDs will increase the quantity of X & Y axis sensors,

which will improve touch resolution.

4. Use of highlighting or sounds to indicate a key has been successfully pressed can be used.

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REFERENCES

BOOKS:

1. Programming and customizing the AVR Microcontroller

(By-Dhananjay V.Gadre)

2. Visual Basic 6 programming

(By-Steven Holzner)

WEBSITES:

www.planar.com

www.atmel.com

www.alldatasheet.com

www.vishay.com
http://www.planar.com/http://www.atmel.com/http://www.alldatasheet.com/http://www.vishay.com/http://www.planar.com/http://www.atmel.com/http://www.alldatasheet.com/http://www.vishay.com/

Low Cost Kiosk Touchscreen

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