remote digital clock

8/13/2019 Remote Digital Clock

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HBeonLabs

Off. No. 46, 1st Floor, Kadamba Complex

Gamma-I, Greater Noida (India) - 201308

Contact us:

+91-120-4298000

+91-9212314779

[email protected]@hbeonlabs.com

www. hbeonlabs.com


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REMOTE CONTROLLED DIGITAL CLOCK


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INTRODUCTION

This Project is made up with AT89C51 and the RTC DS1307. It

has a large seven segment display. The standard remote control

is used to change the Time.

Procedure to enter the Time

1-Press power button on the remote to enter new time

2-Press the Numerical buttons to enter the time

3-Press the Menu button to store the new time

This system has a battery backup, so that the Clock will runduring power failure.

Digital clocks typically use the 50 or 60 hertz oscillation of AC

power or a 32,768 hertz crystal oscillator as in a quartz clock tokeep time. Most digital clocks display the hour of the day in 24

hour format; in the United States and a few other countries, a

more commonly used hour sequence is 12 hour format (with

some indication of AM or PM). Some clocks can display either

time mode according to the owner's preference. Emulations of


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analog-style faces often use an LCD screen, and these are also

sometimes described as "digital".

Some people find difficulty in setting the time in some designs

of digital clocks. Therefore in electronic devices where the clock

is not a critical function, often they are not set at all, displaying

the default after powered on, 00:00 or 12:00.

Since they run on electricity, digital clocks must be reset every

time the power is cut off. This is a particular problem with alarm

clocks that have no "battery" backup, because even a very brief

power outage during the night usually results in the clock failing

to trigger the alarm in the morning.

To reduce the problem, many devices designed to operate on

household electricity incorporate a battery backup to maintain

the time during power outages and during times of disconnection

from the power supply. More recently, some devices incorporate

a method for automatically setting the time, such as using abroadcast radio time signal from an atomic clock, getting the

time from an existing satellite television or computer connection,

or by being set at the factory and then maintaining the time from

then on with a quartz movement powered by an internal

rechargeable battery.


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BRIEF INTRODUCTION TO 8051

MICROCONTROLLER:

When we have to learn about a new computer we have to

familiarize about the machine capability we are using, and we

can do it by studying the internal hardware design (devices

architecture), and also to know about the size, number and the

size of the registers.

A microcontroller is a single chip that contains the

processor (the CPU), non-volatile memory for the program

(ROM or flash), volatile memory for input and output (RAM), a

clock and an I/O control unit. Also called a "computer on a

chip," billions of microcontroller units (MCUs) are embedded

each year in a myriad of products from toys to appliances to

automobiles. For example, a single vehicle can use 70 or more

microcontrollers. The following picture describes a general block

diagram of microcontroller.

AT89S52: The AT89S52 is a low-power, high-performance

CMOS 8-bit microcontroller with 8K bytes of in-system

programmable Flash memory. The device is manufactured using

Atmels high-density nonvolatile memory technology and is


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compatible with the industry-standard 80C51 instruction set and

pin out. The on-chip Flash allows the program memory to be

reprogrammed in-system or by a conventional nonvolatilememory programmer. By combining a versatile 8-bit CPU with

in-system programmable Flash on a monolithic chip, the Atmel

AT89S52 is a powerful microcontroller, which provides a highly

flexible and cost-effective solution to many, embedded control

applications. The AT89S52 provides the following standard

features: 8K bytes of Flash, 256 bytes of RAM, 32 I/O lines,

Watchdog timer, two data pointers, three 16-bit timer/counters, a

six-vector two-level interrupt architecture, a full duplex serial

port, on-chip oscillator, and clock circuitry. In addition, the

AT89S52 is designed with static logic for operation down to zero

frequency and supports two software selectable power saving

modes. The Idle Mode stops the CPU while allowing the RAM,

timer/counters, serial port, and interrupt system to continue

functioning. The Power-down mode saves the RAM con-tents

but freezes the oscillator, disabling all other chip functions until

the next interrupt.


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The pin diagram o

unique to microcon

The following a

microcontroller.

1.Internal ROM and2.I/O ports with prog

3.Timers and counter

4.Serial data commun

the 8051 shows all of the i

rollers:

e some of the capabili

AM

ammable pins

ication

put/output pins

ties of 8051


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The 8051 architecture consists of these specific features:

16 bit PC &data pointer (DPTR)

8 bit program status word (PSW)

8 bit stack pointer (SP)

Internal ROM 4k

Internal RAM of 128 bytes.

4 register banks, each containing 8 registers

80 bits of general purpose data memory

32 input/output pins arranged as four 8 bit ports: P0-P3

Two 16 bit timer/counters: T0-T1

Two external and three internal interrupt sources Oscillator andclock circuits.


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RC-5 PROTOCOL

A common used standard protocol for infrared data

communication is the RC5 code, originally developed by Philips.

This code has an instruction set of 2048 different instructions

and is divided into 32 address for different devices the remote

belongs to like TV,VCR etc. with each address having 64

instructions each for different buttons on the remote. Every kind

of equipment uses his own address, and every button has its own

unique code. So this makes it possible to change the volume of

the TV without change the volume of the stereo.

The transmitted code is a data word which consists

of 14 bits and is defined as:

2 start bits for the automatic gain control in the

infrared receiver.

1 toggle bit (change every time when a new button is pressed on

the ir transmitter).

5 address bits for the system address

6 instruction bits for the pressed key


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We used a single remote to control all the devices so

everything except the toggle bit and the and the command

bits are same. We studied the codes for a particular TV

remote

to be used with our devices.

The next challenge was to get something which would detect

these codes so that Atmega 16 microcontroller would read

these codes. The solution is TSOP 1738.

TSOP 1738:-

The TSOP 17XX series are miniaturized receivers for

infrared remote control systems. PIN diode and preamplifier


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are assembled on lead frame, the epoxy package is designed

as IR filter. The demodulated output signal can directly be

decoded by a microprocessor. TSOP 17XX is the standard

IR remote control receiver series, supporting all major

transmission codes. Here XX refers to the frequency of the

infrared carrier signal on which the code is modulated,

which is 38 KHz in our case. It has three pins .GND and

Vcc are connected

to the power supply with VCC as 5V and Vout which

becomes 0V, or GND when the demodulated bit received is

high i.e. 5V and vice versa.

CODING:-

After we have the code transmitted from the remote on

the press of a button to the microcontroller through the

infrared receiver, we wrote a code using CVAVR, a C

compiler that would make a corresponding port of a

microcontroller high when the incoming code matches

the corresponding button code. We read the incoming

code bit by bit by reading the Vout pin of the sensor to a


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port of the microcontroller. To ensure each bit is read

properly, we used a delay of 889 ms, which is the time

period of the demodulated signal which we receive from

the remote and stored it a character array .As we cannot

store a bit directly in an array due to data type miss-match,

we stored 1 in the array whenever the bit was high and vice

versa. Then we compared the part of the code stored which

changes from button to button i.e. the command bit to

distinguish between different button presses and when a

particular code matches, we make corresponding port high,

i.e. give an output of 5V from that port which depends on

the supply voltage we provide to the microcontroller i.e. if

the supply would have been 6V; the high would

correspond to the port giving 6V. The ON OFF condition

of a device. I.e. the device turns on when we press a button

one time and turns off when we press again is fulfilled by

taking care of the toggle bit. We now needed a device

which would turn a equipment on when it receives a

particular voltage from the microcontroller.


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BLOCK DIAGRAM

CIRCUIT DIAGRAM

8051

MICROCONT

ROLLER

POWER

SUPPLY

IR

REMOTE

TSOP

RTC IC

DS 1307

LCD


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COMPONENT LIST

IREMOTE CONTROLLED DIGITAL CLOCK


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HARDWARE DESCRIPTION:

1.POWER SUPPLY:

Name Capacity Quantity

Regulator 78! "

Regulator 78"# "

Capacitor "$% "

Capacitor "$% "

Ceramic Capacitor ##p% #

Dio&e '

(u)* +utton !

' (in +a)e "

8!" ,AT8-.!#/ "

O)cillator ""0!-#m*1 "

LED 8

Re)i)tance ##2 3

Re)i)tance "4 "

Re)i)tance "4 "

T5.O( "

T6 REMOTE "

RTC D."37 "

+TTON CELL 3 6OLT "

RTC CR.TAL "


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Power supplyis a reference to a source of electrical power. A device

or system that supplies electrical or other types of energy to an output

load or group of loads is called a power supply unit or PSU. The

term is most commonly applied to electrical energy supplies, less

often to mechanical ones, and rarely to others. Here in our application

we need a 5v DC power supply for all electronics involved in the

project. This requires step down transformer, rectifier, voltage

regulator, and filter circuit for generation of 5v DC power. Here a

brief description of all the components are given as follows:

TRANSFORMER:

transformer is a device that transfers electrical energy from one

circuit to another through inductively coupled conductors the

transformer's coils or "windings". Except for air-core transformers, the

conductors are commonly wound around a single iron-rich core, or

around separate but magnetically-coupled cores. A varying current in

the first or "primary" winding creates a varying magnetic field in the

core (or cores) of the transformer. This varying magnetic field induces

a varying electromotive force (EMF) or "voltage" in the "secondary"

winding. This effect is called mutual induction.


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If a load is connected to the secondary circuit, electric charge will

flow in the secondary winding of the transformer and transfer energy

from the primary circuit to the load connected in the secondary circuit.

The secondary induced voltage VS, of an ideal transformer, is scaled

from the primary VP by a factor equal to the ratio of the number of

turns of wire in their respective windings:

By appropriate selection of the numbers of turns, a transformer thus

allows an alternating voltage to be stepped up by making NSmore

than NP or stepped down, by making it

BASIC PARTS OF A TRANSFORMER

In its most basic form a transformer consists of:

A primary coil or winding.

A secondary coil or winding.

A core that supports the coils or windings.


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Refer to the transformer circuit in figure as you read the following

explanation: The primary winding is connected to a 60-hertz ac

voltage source. The magnetic field (flux) builds up (expands) and

collapses (contracts) about the primary winding. The expanding and

contracting magnetic field around the primary winding cuts the

secondary winding and induces an alternating voltage into the

winding. This voltage causes alternating current to flow through the

load. The voltage may be stepped up or down depending on the design

of the primary and secondary windings.

THE COMPONENTS OF A TRANSFORMER

Two coils of wire (called windings) are wound on some type of core

material. In some cases the coils of wire are wound on a cylindrical or

rectangular cardboard form. In effect, the core material is air and the

transformer is called an AIR-CORE TRANSFORMER. Transformers


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According to the con

established by Benjami

today, current is assum

the positive to the ne

conductor nearly alway

In the vast majority of

current flow is irrelev

conventional model is r

In the diagrams below,

the diamond is positive

negative, current flows

along the red (positive

supply terminal via the

When the input connect

connected to the rightc

ventional model of current

Franklin and still followed b

d to flow through electrical

ative pole. In actuality, fre

flow from the negative to t

applications, however, the a

ant. Therefore, in the discu

tained.

when the input connected to

and the input connected to t

from the upper supply ter

path to the output, and retu

lue(negative) path.

ed to the leftcorner is negati

orner is positive, current flow

flow originally

most engineers

conductors from

e electrons in a

e positivepole.

tualdirection of

sion below the

he leftcorner of

e rightcorner is

inal to the right

rns to the lower

ve, and the input

s from the lower


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supply terminal to the

returns to the uppersu

In each case, the upper

output negative. Since t

circuit not only produc

provide what is someti

is, it permits normal

batteries have been ins

from a DC power so

equipment from potenti

Prior to availability of

was always constructed

a single four-termina

connected in the bridge

right along the red path to

ply terminal via the bluepath

right output remains positiv

is is true whether the input i

s a DC output from an AC i

es called "reverse polarity

unctioning of DC-powered

talled backwards, or when t

urce have been reversed,

l damage caused by reverse p

integrated electronics, such

from discrete components. S

l component containing t

configuration became a stan

the output, and

.

and lower right

AC or DC, this

nput, it can also

rotection". That

quipment when

he leads (wires)

nd protects the

olarity.

bridge rectifier

ince about 1950,

e four diodes

ard commercial


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component and is no

ratings.

OUTPUT SMOOTHI

For many applications,

full-wave bridge serves

addition of a capacito

supplies an output of

"pulsating" magnitude (

The function of this csmoothing capacitor) i

rectified AC output

explanation of 'smoot

impedance path to the

voltage across, and A

technical terms, any d

available with various vol

G

especially with single phas

to convert an AC input into

may be desired because t

fixed polarity but continuo

ee diagram above).

pacitor, known as a reservto lessen the variation in

voltage waveform from t

ing' is that the capacitor

C component of the output,

current through, the resisti

op in the output voltage an

age and current

AC where the

DC output, the

he bridge alone

usly varying or

ir capacitor (oror 'smooth') the

e bridge. One

provides a low

reducing the AC

ve load. In less

d current of the


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bridge tends to be canceled by loss of charge in the capacitor. This

charge flows out as additional current through the load. Thus the

change of load current and voltage is reduced relative to what would

occur without the capacitor. Increases of voltage correspondingly

store excess charge in the capacitor, thus moderating the change in

output voltage / current.

The simplified circuit shown has a well-deserved reputation for being

dangerous, because, in some applications, the capacitor can retain a

lethal charge after the AC power source is removed. If supplying a

dangerous voltage, a practical circuit should include a reliable way to

safely discharge the capacitor. If the normal load cannot be guaranteed

to perform this function, perhaps because it can be disconnected, the

circuit should include a bleeder resistor connected as close as practical

across the capacitor. This resistor should consume a current large

enough to discharge the capacitor in a reasonable time, but small

enough to minimize unnecessary power waste.

Because a bleeder sets a minimum current drain, the regulation of the

circuit, defined as percentage voltage change from minimum to

maximum load, is improved. However in many cases the

improvement is of insignificant magnitude.


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of a bridge, the bridge diodes must be sized to withstand the current

surge that occurs when the power is turned on at the peak of the AC

voltage and the capacitor is fully discharged. Sometimes a small series

resistor is included before the capacitor to limit this current, though in

most applications the power supply transformer's resistance is already

sufficient.

Output can also be smoothed using a choke and second capacitor. The

choke tends to keep the current (rather than the voltage) more

constant. Due to the relatively high cost of an effective choke

compared to a resistor and capacitor this is not employed in modern

equipment.

Some early console radios created the speaker's constant field with the

current from the high voltage ("B +") power supply, which was then

routed to the consuming circuits, (permanent magnets were then too

weak for good performance) to create the speaker's constant magnetic

field. The speaker field coil thus performed 2 jobs in one: it acted as a

choke, filtering the power supply, and it produced the magnetic field

to operate the speaker.

REGULATOR IC (78XX)


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It is a three pin IC used as a voltage regulator. It converts unregulated

DC current into regulated DC current.

Normally we get fixed output by connecting the voltage regulator at

the output of the filtered DC (see in above diagram). It can also be

used in circuits to get a low DC voltage from a high DC voltage (for

example we use 7805 to get 5V from 12V). There are two types of

voltage regulators 1. fixed voltage regulators (78xx, 79xx) 2. variable

voltage regulators(LM317) In fixed voltage regulators there is another

classification 1. +ve voltage regulators 2. -ve voltage regulators

POSITIVE VOLTAGE REGULATORS This include 78xx voltage


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regulators. The most commonly used ones are 7805 and 7812. 7805

gives fixed 5V DC voltage if input voltage is in (7.5V, 20V).

The Capacitor Filter

The simple capacitor filter is the most basic type of power supply

filter. The application of the simple capacitor filter is very limited. It is

sometimes used on extremely high-voltage, low-current power

supplies for cathode-ray and similar electron tubes, which require very

little load current from the supply. The capacitor filter is also used

where the power-supply ripple frequency is not critical; this frequency

can be relatively high. The capacitor (C1) shown in figure 4-15 is a

simple filter connected across the output of the rectifier in parallel

with the load.

Full-wave rectifier with a capacitor filter.

When this filter is used, the RC charge time of the filter capacitor (C1)

must be short and the RC discharge time must be long to eliminate

ripple action. In other words, the capacitor must charge up fast,


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preferably with no discharge at all. Better filtering also results when

the input frequency is high; therefore, the full-wave rectifier output is

easier to filter than that of the half-wave rectifier because of its higher

frequency.

For you to have a better understanding of the effect that filtering has

on Eavg, a comparison of a rectifier circuit with a filter and one without

a filter is illustrated in views A and B of figure 4-16. The output

waveforms in figure 4-16 represent the unfiltered and filtered outputs

of the half-wave rectifier circuit. Current pulses flow through the load

resistance (RL) each time a diode conducts. The dashed line indicates

the average value of output voltage. For the half-wave rectifier, Eavgis

less than half (or approximately 0.318) of the peak output voltage.

This value is still much less than that of the applied voltage. With no

capacitor connected across the output of the rectifier circuit, the

waveform in view A has a large pulsating component (ripple)

compared with the average or dc component. When a capacitor is

connected across the output (view B), the average value of output

voltage (Eavg) is increased due to the filtering action of capacitor C1.

UNFILTERED


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The rate of charge for the capacitor is limited only by the resistance of

the conducting diode, which is relatively low. Therefore, the RC

charge time of the circuit is relatively short. As a result, when the

pulsating voltage is first applied to the circuit, the capacitor charges

rapidly and almost reaches the peak value of the rectified voltage

within the first few cycles. The capacitor attempts to charge to the

peak value of the rectified voltage anytime a diode is conducting, and

tends to retain its charge when the rectifier output falls to zero. (The

capacitor cannot discharge immediately.) The capacitor slowly

discharges through the load resistance (RL) during the time the

rectifier is non-conducting.

The rate of discharge of the capacitor is determined by the value of

capacitance and the value of the load resistance. If the capacitance and

load-resistance values are large, the RC discharge time for the circuit

is relatively long.

A comparison of the waveforms shown in figure 4-16 (view A and

view B) illustrates that the addition of C1 to the circuit results in an

increase in the average of the output voltage (Eavg) and a reduction in

the amplitude of the ripple component (Er) which is normally present

across the load resistance.


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Now, let's consider a complete cycle of operation using a half-wave

rectifier, a capacitive filter (C1), and a load resistor (RL). As shown in

view A of figure 4-17, the capacitive filter (C1) is assumed to be large

enough to ensure a small reactance to the pulsating rectified current.

The resistance of RLis assumed to be much greater than the reactance

of C1 at the input frequency. When the circuit is energized, the diode

conducts on the positive half cycle and current flows through the

circuit, allowing C1 to charge. C1 will charge to approximately the

peak value of the input voltage. (The charge is less than the peak value

because of the voltage drop across the diode (D1)). In view A of the

figure, the charge on C1 is indicated by the heavy solid line on the

waveform. As illustrated in view B, the diode cannot conduct on the

negative half cycle because the anode of D1 is negative with respect to

the cathode. During this interval, C1 discharges through the load

resistor (RL). The discharge of C1 produces the downward slope as

indicated by the solid line on the waveform in view B. In contrast to

the abrupt fall of the applied ac voltage from peak value to zero, the

voltage across C1 (and thus across RL) during the discharge period

gradually decreases until the time of the next half cycle of rectifier

operation. Keep in mind that for good filtering, the filter capacitor

should charge up as fast as possible and discharge as little as possible.


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the anode of the diode exceeds the voltage on the charge remaining on

C1. The charge on C1 is the cathode potential of the diode. When the

potential on the anode exceeds the potential on the cathode (the charge

on C1), the diode again conducts, and C1 begins to charge to

approximately the peak value of the applied voltage.

After the capacitor has charged to its peak value, the diode will cut off

and the capacitor will start to discharge. Since the fall of the ac input

voltage on the anode is considerably more rapid than the decrease on

the capacitor voltage, the cathode quickly become more positive than

the anode, and the diode ceases to conduct.

Operation of the simple capacitor filter using a full-wave rectifier is

basically the same as that discussed for the half-wave rectifier.

Referring to figure 4-18, you should notice that because one of the

diodes is always conducting on. either alternation, the filter capacitor

charges and discharges during each half cycle. (Note that each diode

conducts only for that portion of time when the peak secondary

voltage is greater than the charge across the capacitor.)

Figure 4-18. - Full-wave rectifier (with capacitor filter).


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Another thing to keep in mind is that the ripple component (Er) of the

output voltage is an ac voltage and the average output voltage (Eavg) is

the dc component of the output. Since the filter capacitor offers a

relatively low impedance to ac, the majority of the ac component

flows through the filter capacitor. The ac component is therefore

bypassed (shunted) around the load resistance, and the entire dc

component (or Eavg) flows through the load resistance. This statement

can be clarified by using the formula for XC in a half-wave and full-

wave rectifier. First, you must establish some values for the circuit.


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As you can see from the

rectifier, you reduce the

calculations, by doubling the

impedance of the capacitor b

frequency of the

one-half. This


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allows the ac componen

a result, a full-wave rec

a half-wave rectifier. R

capacitor with respect t

action. Since

the largest possible cap

Remember, also, that th

If load resistance is m

average value of outpu

time constant is a direc

therefore, the rate of ca

the current through the

rapid the discharge of t

of output voltage. For

seldom used with recti

load current. Using the

full-wave or bridge rec

increased ripple freque

filter capacitor.

t to pass through the capacito

ifier output is much easier to

member, the smaller the XCo

the load resistance, the bette

citor will provide the best filt

load resistance is an import

de small, the load current i

t voltage (Eavg) decreases. T

t function of the value of th

acitor voltage discharge is a

load. The greater the load c

he capacitor, and the lower t

this reason, the simple ca

ier circuits that must supply

simple capacitive filter in co

tifier provides improved filte

cy decreases the capacitive

more easily. As

ilter than that of

the filter

the filtering

ring.

nt consideration.

creases, and the

e RC discharge

load resistance;

irect function of

urrent, the more

e average value

acitive filter is

relatively large

njunction with a

ring because the

reactance of the


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CIRCUIT DIAGRAM OF POWER SUPPLY

T-SOP 17 SERIES:

DESCRIPTION

The TSOP17.. series are miniaturized receivers for infrared remote control

systems. PIN diode and preamplifier are assembled on lead frame, the epoxy

package is designed as IR filter. The demodulated output signal can directly be


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decoded by a microprocessor. TSOP17.. is the standard IR remote control

receiver series, supporting all major transmission codes.

FEATURES

Photo detector and preamplifier in one package

Internal filter for PCM frequency Improved shielding against electrical field disturbance

TTL and CMOS compatibility

Output active low

Low power consumption

High immunity against ambient light

Continuous data transmission possible (up to 2400 bps)

Suitable burst length .10 cycles/burst


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Display Section:

LIQUID CRYSTL DIS!LY

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,normally organic %or LCD:)/ t*at ;ill %lo; li4e a li9ui&


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n&er &ar4 con&ition)> it ;oul& a re%lector can


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T*e a ;*ic* are limite& to num t*ere t*e

LED mu)t


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T*e LCD u)e& *ere *a)


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! .*i%t &i)play le%t

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'ORIN%:

T*e inter%ace u)e&


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eight bit transfer. The "Enable" Clock is used to initiate the data

transfer within the LCD.

Sending parallel data as either four or eight bits are the two primary

modes of operation. While there are secondary considerations and

modes, deciding how to send the data to the LCD is most critical

decision to be made for an LCD interface application.

Eight bit mode is best used when speed is required in an application

and at least ten I/O pins are available. Four bit mode requires a

minimum of six bits. To wire a microcontroller to an LCD in four bit

mode, just the top four bits (DB4-7) are written to.

The "RS" bit is used to select whether data or an instruction is being

transferred between the microcontroller and the LCD. If the Bit is set,

then the byte at the current LCD "Cursor" Position can be read or

written. When the Bit is reset, either an instruction is being sent to the

LCD or the execution status of the last instruction is read back

(whether or not it has completed).

Rea&ing Data


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groun&e& RJ pin ;*ic* mean) ;e are not retrie?ing any &ata %rom

LCD0

The LCD can be thought of as a "Teletype" display because in normal

operation, after a character has been sent to the LCD, the internal

"Cursor" is moved one character to the right. The "Clear Display" and

"Return Cursor and LCD to Home Position" instructions are used to

reset the Cursor's position to the top right character on the display.

To move the Cursor, the "Move Cursor to Display" instruction is used.

For this instruction, bit 7 of the instruction byte is set with the

remaining seven bits used as the address of the character on the LCD

the cursor is to move to. These seven bits provide 128 addresses,

which matches the maximum number of LCD character addresses

available.


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Eight programmable characters are available and use codes 0x000 to

0x007. They are programmed by pointing the LCD's "Cursor" to the

Character Generator RAM

The last aspect of the LCD to discuss is how to specify a contrast

voltage to the Display. I typically use a potentiometer wired as a

voltage divider. This will provide an easily variable voltage between

Ground and Vcc, which will be used to specify the contrast (or

"darkness") of the characters on the LCD screen. You may find that

different LCDs work differently with lower voltages providing darker

characters in some and higher voltages do the same thing in others

CIRCUIT DIAGRAM OF LCD INTERFACING


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Optional in&u)trial temperature range 5'C to H8!C

Available in 8-pin DIP or SOIC Underwriters Laboratory (UL)

recognized

PIN DESCRIPTION

6CC 5 (rimary (o;er .upply

P"> P# 5 3#07841 Cry)tal Connection

6+AT 5 H36 +attery Input

GND 5 Groun&

.DA 5 .erial Data

.CL 5 .erial Cloc4

.QJOT 5 .9uare a?eJOutput Dri?er

DESCRIPTION


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T*e D."37 .erial Real5Time Cloc4 i) a lo;5po;er>

%ull

&ay> &ate> mont*> an& year in%ormation0 T*e en& o% t*e mont* &ate i)

automatically a&Bu)te& %or mont*) ;it* %e;er t*an 3" &ay)> inclu&ing

correction) %or leap year0 T*e cloc4 operate) in eit*er t*e #'5*our or

"#5*our %ormat ;it* AMJ(M in&icator0 T*e D."37 *a) a


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VISION

The Vision IDE is, for most developers, the easiest way to

create embedded system programs. This chapter describes

commonly used Vision features and explains how to use them.

General Remarks and Concepts

Before we start to describe how to use Vision, some general

remarks, common to many screens1 and to the behavior of the

development tool, are presented. In our continuous effort todeliver best-in-class development tools, supporting you in your

daily work, Vision has been built to resemble the look-and-feel

of widespread applications. This approach decreases your

learning curve, such that

you may start to work with Vision right away.

Based on the concept of windows:


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Vision windows can be re-arranged, tiled, and attached to

other screen areas or windows respectively It is possible to drag

and drop windows, objects, and variables

A Context Menu, invoked through the right mouse button, is

provided for most objects. You can use keyboard shortcuts and

define your own shortcuts. You can use the abundant features of

a modern editor. Menu items and Toolbar buttons are greyed out

when not available in the Current context.

Graphical symbols are used to resemble options, to mark

unsaved changes, or reveal objects not included into the project.

Status Bars display context-driven information.You can

associate Vision to third-party tools


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The Project Windows area is that part of the screen in which,

by default, the Project Window, Functions Window, Books

Window, and Registers Window are displayed.

Within the Editor Windows area, you are able to change the

source code, view performance and analysis information, and

check the disassembly code.

The Output Windows area provides information related to

debugging, memory, symbols, call stack, local variables,

commands, browse information, and find in files results.

If, for any reason, you do not see a particular window and have

tried displaying/hiding it several times, please invoke the default

layout of Vision through the Window Reset Current

Layout Menu.

Positioning Windows

The Vision windows may be placed onto any area of the

screen, even outside of the Vision frame, or to another physical

screen.


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Click and hold the Title Bar1 of a window with the left mouse

button

Drag the window to the preferred area, or onto the preferred

control, and release the mouse button

Please note, source code files cannot be moved outside of the

Editor Windows2.\ Invoke the Context Menu of the windows

Title Bar to change the docking attribute of a window object. Insome cases, you must perform this action before you can drag

and drop the window.

Vision displays docking helper controls3, emphasizing the area

where the window will be attached. The new docking area is

represented by the section highlighted in blue. Snap the window

to the Multiple Document Interface (MDI) or to a Windows area

by moving the mouse over the preferred control.


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remote digital clock

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