principles of embedded system lab manual

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TECHNOLOGICAL INSTITUTE OF THE PHILIPPINES

PRINCIPLE OF EMBEDDED SYSTEM

LABORATORY ACTIVITY MANUAL

By:

Engr. Ronnie M. Dysangco

Engr. Maria Cecilia A. Venal


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Table of Contents

INTRODUCTION .................................................................................................................................3

ACTIVITIES .........................................................................................................................................5

Activity No. 1 .........................................................................................................................6

SERIAL MONITOR DISPLAY .........................................................................................6

Activity No. 2 ....................................................................................................................... 10

LIGHT EMITTING DIODE (LED) DISPLAY ..................................................................... 10

Activity No. 3 ....................................................................................................................... 15

RGB (LED) DISPLAY ................................................................................................... 15

Activity No. 4 ....................................................................................................................... 21

LED LIGHTS, SHIFT REGISTER AND SERIAL MONITOR ................................................. 21

Activity No. 5 ....................................................................................................................... 30

DIGITAL INPUTS ....................................................................................................... 30

Activity No. 6 ....................................................................................................................... 34

RGB LED FADER ........................................................................................................ 34

Activity No. 7 ....................................................................................................................... 39

ANALOG INPUTS ...................................................................................................... 39

Activity No. 8 ....................................................................................................................... 44

SENSOR AND SOUNDS .............................................................................................. 44

Activity No. 9 ....................................................................................................................... 50

LCD DISPLAY ............................................................................................................ 50

Activity No. 10 ..................................................................................................................... 56

MOTORS .................................................................................................................. 56

Appendix ......................................................................................................................................... 70


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INTRODUCTION

Embedded System

It is housed on a single microprocessorboard with theprograms stored inROM.Virtually all appliances thathave adigital interface -- watches, microwaves, VCRs, cars -- utilize embedded systems. Some embedded

systems include anoperating system,but many are specialized where the entire logic can be implemented

as a single program.

Breadboard

Breadboard is a way of constructing electronics without having to use a soldering iron. Components are

pushed into the sockets on the breadboard and then extra 'jumper' wires are used to make connections.

The middle section of the board has two columns, each with 30 strips of connector, like the one pulled out

and to the side of the breadboard. These connect together anything that is pushed through from the frontinto one of those five holes.

On either edge of the board are much longer sections of clip that join together the columns of holes marked

by the blue and red lines on the front of the breadboard. These are generally used for GND (blue) and 5V

(red).

Getting Started

Figure A. Device Detection
http://www.webopedia.com/TERM/B/board.htmlhttp://www.webopedia.com/TERM/P/program.htmlhttp://www.webopedia.com/TERM/R/ROM.htmlhttp://www.webopedia.com/TERM/D/digital.htmlhttp://www.webopedia.com/TERM/O/operating_system.htmlhttp://www.webopedia.com/TERM/O/operating_system.htmlhttp://www.webopedia.com/TERM/D/digital.htmlhttp://www.webopedia.com/TERM/R/ROM.htmlhttp://www.webopedia.com/TERM/P/program.htmlhttp://www.webopedia.com/TERM/B/board.html


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Figure B. Update Driver Software


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ACTIVITIES


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Activity No. 1

SERIAL MONITOR DISPLAY

Course Code: CPE 131 Program:

Course Title: Principle of Embedded System Date Performed:Section: Date Submitted:

Name : Instructor:

1. Objective(s):

The activity aims to create a runnable program using the Arduino programming software. This activityalso provides students with knowledge and skills on how to develop a program using the Arduinoprogramming software.

2. Intended Learning Outcomes (ILOs):

The students shall be able to:2.1Create a program that displays a string output and some mathematical operation.2.2Apply the C-programming knowledge in embedded system programming.

3. Discussion:

Serial Library is used to communicate from the Arduino/Gizduino board back to the computer over theUSB port. Serial data transfer sequence is through one bit data transfer at a time, in which theinformation is passed back & forth between the computer and Arduino/ Gizduino board by, essentially,setting the pin into a high or low status. Just like using the LED lights as an indicator for the output. The

connection of the Arduino/Gizduino board as shown in Figure 1-1 emphasizes the data transfer physicalprocedure from the software going to the Arduino/Gizduino board.

Figure 1-1 Hardware Connection


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Creating a program file with Arduino/Gizduino board is the same as the C language source code.

Reference:http://www.ladyada.net/learn/arduino/lesson4.html

4. Materials and Equipment:

1.

Arduino/Gizduino board2. Computer3. USB Cable4. Power Source

5. Procedure:

1. Open installed Arduino IDE.2. Select board and serial port in the action bar.3. Create a new sketch.4. Copy the source code in Figure 1-2.

Figure 1-2 String sample source code5. Compile the program.6. Save the program as Activity 1-1.7. Simulate the program.8. Write the output at the data and results.
http://www.ladyada.net/learn/arduino/lesson4.htmlhttp://www.ladyada.net/learn/arduino/lesson4.htmlhttp://www.ladyada.net/learn/arduino/lesson4.htmlhttp://www.ladyada.net/learn/arduino/lesson4.html


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9. Create a new sketch.10.Copy the source code below.

/* * Math is fun! * */

int a = 5;int b = 10;

int c = 20;

void setup() // run once, when the

sketch starts

{

Serial.begin(9600); // set up Serial library

at 9600 bps

Serial.println("Mathematical Operation: ");

Serial.print("a = ");

Serial.println(a);

Serial.print("b = ");

Serial.println(b);

Serial.print("c = ");

Serial.println(c);

Serial.print("a + b = "); // add

Serial.println(a + b);

Serial.print("a * c = "); // multiply

Serial.println(a * c);

Serial.print("c / b = "); // divide

Serial.println(c / b);

Serial.print("b - c = "); // subtract

Serial.println(b - c);

}

void loop() // we need this to be

here even though its empty

{}

11.Compile the program.12.Save the file as Activity 1-2.13.Simulate the program.14.Write the output at the data and results.


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6. Data and Results:

7. Data Analysis:

8. Assessment Rubric:


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Activity No. 2

LIGHT EMITTING DIODE (LED) DISPLAY

Course Code: CPE 131 Program:Course Title: Principle of Embedded System Date Performed:

Section: Date Submitted:

Name : Instructor:

1. Objective(s):

The activity aims to create a runnable program using the Arduino programming software that will displayan LED output. This activity also provides students knowledge and skills on how to develop a circuitusing different resistor in controlling the LED using the Arduino programming software.


The students shall be able to:2.1Create a runnable program that will display a different LED.2.2Apply the C-programming knowledge in embedded system programming.

3. Discussion:

Light Emitting Diode

LEDs are one of the good electronic outputs that make a great light indicator output. It is an electronic

device that uses a very little electricity. The most common of all LEDs a 5mm red LED refers to thediameter of the LED. Other common sizes are 3mm and the large fun 10mm LEDs. This electronicdevice cannot be connected directly to a battery or any voltage source because of it s voltage necessity.The polarity of each leg needs to be attached to a resistor to limit or choke the amount of currentflowing to avoid the burn out probability.

Resistors

It is an electronic component that resists the electricity flow, in which the higher the value of the resistor,the more it can resist the electrical charge and produce less electrical current within the circuitry. Todetermine the amount of resistance of each resistor, Figure 2-1 shows the proper way on reading the

resistor color coding values.

Blink Source Code

Blinking is one of the methods in controlling the LED light output of the Arduino/Gizduino board. It is alsothe basic programming technique on how to manipulate and embedded a program on the said board.Figure 2-2 shows the source code in creating a blinking program.


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Figure 2-1 Resistor Color Coding

Figure 2-2 Blink Program


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1. Arduino/Gizduino board2. Computer3. USB Cable

4.

Power Source5. Bread board6. LED7. Resistors (470, 2.2K, and 10K)8. 74HC595 Shift Register9. Connecting wires

5. Procedure:

1. Open Sketch software.2. Choose example at file menu.3. Select basic then blink.

4.

Write the source code at the data and results.5. Save the file as Activity 2-A.6. Attach the Arduino or Gizduino Board with the USB cable.7. Click the upload button.8. Simulate the program.9. Write the binary sketch size and error message at data and results.10.Change and write the observation as the delay values change using Table 2-1.11.Create a connection as shown in Figure 2-3.

Figure 2-3 Bread board interface

12.

Write the output at Table 2-2.13.Create a connection as shown in Figure 2-4.


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Binary Sketch size:

Error Message

Figure 2-4 Blinking Connection

14.Modify the int led values as using the data in Table 2-3.15.Simulate the program.16.Fill-out Table 2-3.


Source Code (Procedure 4)


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Table 2-1 Delay

Delay Values Observation

1. 100

2. 3003. 500

4. 700

5. 900

Table 2-2 LED Output

ResistorValue

Output

1. 470

2. 2.2K

3. 10K

Table 2-3 Blinking Output

int led Value Observation

1. 13

2. 7

3. 10

4. 100

5. 30

7. Data Analysis:



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Activity No. 3

RGB (LED) DISPLAY



Name : Instructor:

1. Objective(s):

The activity aims to create a runnable program using the Arduino programming software that will displayan RGB LED output. This activity also provides students with knowledge and skills on how to develop acircuit using RGB LED controlled by C programming.


The students shall be able to:2.1Create a runnable program that will display a RGB LED output.2.2Apply the C-programming knowledge in embedded system programming.

3. Discussion:

RGB LEDs

It is a type of LED that contains different color combination such as Red, Green and Blue inside a single

LED bulb. A common anode RGB LED is nothing more complicated than three one colour LEDs (onered, one green, and one blue) housed in a single package. Rather than having 6 leads (a cathode andanode for each LED) it has only 4 one cathode for each colour, and one common anode. (see theschematic diagram below) A common anode RGB LED is the most popular type. It is commonly found ineither a 5mm bulb size or as a 5mm pirahna form factor as shown in Figure 3-1.

Figure 3-1 RGB LED Pin-out


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Current Limiting Resistors (270 ohm) (red-purple-brown)

Most LEDs are designed to work with a voltage between 1.5v and 3v. As most microcontrollers(including the Arduino) operate on 5 volts a current limiting resistor is required.

Consult your LEDs datasheet for maximum ratings but we like to use 270 ohm resistors. This limits thecurrent to ~20mA, well within most LEDs and microcontroller ratings. Figure 3-1 shows the testschematic for RGB LED.

Figure 3-1 RGB Test SchematicPulse Width Modulation (PWM)

It is a technique for power controlling. It is also used to control the brightness of each RGB LEDs.Roughly every 1/500 of a second, the PWM output will produce a pulse. The length of this pulse iscontrolled by the 'analogWrite' function. So 'analogWrite(0)' will not produce any pulse at all and'analogWrite(255)' will produce a pulse that lasts all the way until the next pulse is due, so that the

output is actually on all the time. If the specify value in the analogWrite that is somewhere in between 0and 255 then it will produce a pulse. If the output pulse is only high for 5% of the time then whatever weare driving will only receive 5% of full power. However, the output is at 5V for 90% of the time then theload will get 90% of the power delivered to it.

Reference:www.instructables.com/id/RGB-LED-Tutorial-using-an-Arduino-RGBL/step1/Parts/


1. Arduino/Gizduino board2. Computer

3.

USB Cable4. Power Source5. Bread board6. RGB LED7. Resistors (270 , 470, 500, and 1K)8. Connecting wires
http://www.instructables.com/id/RGB-LED-Tutorial-using-an-Arduino-RGBL/step1/Parts/http://www.instructables.com/id/RGB-LED-Tutorial-using-an-Arduino-RGBL/step1/Parts/http://www.instructables.com/id/RGB-LED-Tutorial-using-an-Arduino-RGBL/step1/Parts/http://www.instructables.com/id/RGB-LED-Tutorial-using-an-Arduino-RGBL/step1/Parts/


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5. Procedure:

1. Open Sketch software.2. Create a circuit and board connection as shown in Figure 3-4.

Figure 3-4. RGB Breadboard Connection


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3. Copy the source code at Figure 3-5.

Figure 3-5 RGB LED Source Code

4. Simulate the program.5.

Determine the output at Table 3-1.6. Draw the PWM graph at the data and results for the given signals below

a. 1/20b. 10/20c. 18/20

7. Draw a PCB design at the space provided.


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Table 3-1 Color Settings

Color Settings Output

1. 255,0,02. 0,255,0

3. 0,0,2554. 255,255,0

5. 80,0,80

6. 0,255,255

7. 0x4B,0x0,0x82

8. 0x3A,0xDF,0x00

9. 0x24,0x3B,0x0B

10. 0x00,0xFF,0x00

1/20 10/20 18/10


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PCB Design

7. Data Analysis:



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Activity No. 4

LED LIGHTS, SHIFT REGISTER AND SERIAL MONITOR



Name : Instructor:

1. Objective(s):

The activity aims to create a runnable program using the Arduino programming software that will displayan LED and serial monitor output using Shift Register IC. This activity also provides students withknowledge and skills on how to develop a circuit using Shift Register IC controlled by C programmingcode.


The students shall be able to:2.1Create a runnable program that will display an LED and serial monitor output.2.2Apply the C-programming knowledge in embedded system programming.

3. Discussion:

74HC595 as an "8-bit serial-in, serial or parallel-out shift register with output latches; 3-state." In otherwords, it can be used to control 8 outputs at a time while taking only a few pins on the microcontroller. It

can be link multiple registers together to extend to even more output. (Users may also wish to search forother driver chips with "595" or "596" in their part numbers, there are many. The STP16C596 forexample will drive 16 LED's and eliminate the series resistors with built-in constant current sources.)

This integrated circuit work in a "synchronous serial communication," i.e. it can pulse one pin up anddown thereby communicating a data byte to the register bit by bit. It's by pulsing second pin, the clockpin, which can delineate between bits. This is in contrast to using the "asynchronous serialcommunication" of the Serial.begin() function which relies on the sender and the receiver to be setindependently to an agreed data rate.

Once the whole byte is transmitted to the register the HIGH or LOW messages held in each bit get

parceled out to each of the individual output pins. This is the "parallel output" part, having all the pins doall at once.

The "serial output" part of this component comes from its extra pin which can pass the serial informationreceived from the microcontroller out again unchanged. This means that it can transmit 16 bits in a row(2 bytes) and the first 8 will flow through the first register into the second register and be expressedthere.


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"3 states" refers to the fact that can set the output pins as either high, low or "high impedance." Unlikethe HIGH and LOW states, it cannot set pins to high impedance state individually. It can only set thewhole chip together. This is a pretty specialized thing to do for example think of a LED array that mightneed to be controlled by completely different microcontrollers depending on a specific mode setting built

into a project. Figure 4-1 shows the pin configuration of 74HC595

Figure 4-1 595 Pin Configuration
http://en.wikipedia.org/wiki/High_impedancehttp://en.wikipedia.org/wiki/High_impedance


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Shift registers hold an eight memory location as shown in Figure 4-2.

Figure 4-2 Pin Configuration and Pulse


1. Arduino/Gizduino board2. Computer

3.

USB Cable4. Power Source5. Bread board6. 8 LED7. 8 Resistors (270 )8. Connecting wires


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5. Procedure:

1. Create a Circuit and board connection as shown in Figure 4-3.

Figure 4-3 8 LED Lights Circuit2. Open Sketch software.3. Copy the source code at Figure 4-4


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Figure 4-4 8 LED Lights Code

4. Simulate the program.5. Fill-up Table 4-1.6. Save the program as Activity 4-1.


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7. Create a new file.8. Copy the program at Figure 4-5.

Figure 4-5 Shift RegisterBrightness Source Code

9. Simulate the program.


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10.Fill-out Table 4-2.11.Save the program as Activity 4-2.12.Create a new file.13.Copy the program at Appendix A.14.Save the program as Activity 4-3.

15.

Simulate the program.16.Draw the sequential output at the data and results.17.Create a new file.18.Copy the program at Figure 4-6.

Figure 4-6 Serial Monitor Code

19.Determine the output at COM4.20.Write the COM4 output at the data and results21.Fill-out Table 4-3.


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Sequential Output


Table 4-1. Display Modification

Case Output Observation

pinMode(latchPin,INPUT)

pinMode(dataPin,INPUT)

pinMode(clockPin,INPUT)led=1

i=1

i>8

i--

delay(100)

delay(1000)

delay(1500)

BothdigitalWrite(latchPin,High)

Both

digitalWrite(latchPin,Low)

Table 4-2. Brightness Modification


setBrightness(400), delay(1000)






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Table 4-3. Baud Rate

Case COM4 Output Observation

4800 baud

14400 baud19200 baud

28800 baud38400 baud

57600 baud

115200 baud

7. Data Analysis:



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Activity No. 5

DIGITAL INPUTS



Name : Instructor:

1. Objective(s):

The activity aims to create a runnable program using the Arduino programming software that will displayan LED light output controlled by a tactile push switch. This activity also provides students withknowledge and skills on how to develop a circuit using C-programming codes.


The students shall be able to:

2.1Create a runnable program that will display an LED light output controlled by a switch.2.2Apply the C-programming knowledge in embedded system programming.

3. Discussion:

Switches are really simple electronic components. When the user presses a button or flips a lever, itconnects two contacts together so that electricity can flow through the circuit. The little tactile switches

are a kind of switch that has four connections, which can be a little confusing. In reality, there are onlytwo electrical connections, as inside the switch package pins B and C are connected together, like the Aand D as shown in Figure 5-1.

Figure 5-1 Tactile Switch


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4.

Power Source5. Bread board6. 2 Tactile push switch7. 8 LED Lights8. 8 Resistors (270 )9. Connecting wires

5. Procedure:

1. Create a circuit connection as shown in Figure 5-2.

Figure 5-2 Breadboard Connection


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2. Open Sketch software.3. Copy the program in Figure 5-3

Figure 5-3 Source Code4. Fill-out Table 5-1.5. Save the program as Activity 5-1.6. Draw a schematic diagram for the circuit at the data and results7. Write a runnable program at the data and result using whilefunction.





pinMode(buttonApin,INPUT_PULLDOWN)

pinMode(buttonBpin,INPUT_PULLDOWN)

pinMode(buttonApin,INPUT_PULLDOWN)pinMode(buttonBpin,INPUT_PULLDOWN)

digitalWrite(ledPin,LOW)

digitalRead(buttonBpin)==HIGH


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Schematic Diagram While function Source Code

7. Data Analysis:



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Activity No. 6

RGB LED FADER



Name : Instructor:

1. Objective(s):

The activity aims to create a runnable program using the Arduino programming software that will displayan RGB LED lights common cathode output. This activity also provides students with knowledge andskills on how to develop a circuit using C programming source code.


The students shall be able to:2.1Create a runnable program that will display an RGB LED lights output controlled by a C-

program.2.2Apply the C-programming knowledge in embedded system programming.

3. Discussion:

LEDs (ell-ee-dees) are a particular type ofdiode that convert electrical energy into light. In fact, LEDstands for Light Emitting Diode. This is reflected in the similarity between the diode and LED schematic

symbols:

In short, LEDs are like tiny lightbulbs. However, LEDs require a lot less power to light up by comparison.They are also more energy efficient, so they do not tend to get hot like conventional light bulbs do. Thismakes them ideal for mobile devices and other low-power applications.

RGB LED in a 5mm diffused epoxy case. - Common Cathode (common ground) as shown in Figure 6-18,000mcd- 100,000nhour lifetime as shown in Table 6-1.

Table 6-1 RGB Colors Description

Red: 2V ~ 2.4V20

mA

Green:3.2V ~3.6V

20mA

Blue:3.2V ~3.6V

20mA
https://learn.sparkfun.com/tutorials/diodes/introductionhttps://learn.sparkfun.com/tutorials/diodes/introduction


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Figure 6-1 RGB Pin Configuration

Reference:www.chromationsystems.com/store/index.php?main_page=product_info&products_id=182


1. Arduino/Gizduino board2. Computer3. USB Cable4. Power Source5. Bread board6. RGB LED (Common Cathode)7. 3 Tactile Push Switches8. 8 Resistors (270 )

9.

2x2 Printed Circuit Board10.Ferric Chloride11.Plastic Container12.Permanent Marker13.Masking Tape14.Mini Drill15.Connecting wires


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5. Procedure:

1. Create a Breadboard connection as shown in Figure 6-1.

Figure 6-1 RGB and Switches Breadboard Connection

2.

Draw a schematic diagram at the data and results.3. Open Sketch software.4. Copy the program in Figure 6-2.


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Figure 6-2 Source Code5. Simulate the program.6.

Save the file as Activity 6-1.7. Fill-out Table 6-1 at the data and results.8. Design a PCB layout for Figure 6-1.


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Schematic Diagram




if (digitalRead(redSwitchPin)==HIGH)red--

if(red


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Activity No. 7

ANALOG INPUTS



Name : Instructor:

1. Objective(s):

The activity aims to create a runnable program using the Arduino programming software that will displayan EIGHT LED lights output controlled by a Variable resistor and design PCB Circuit and connection.This activity also provides students with knowledge and skills on how to develop a circuit using analoginput circuit controlled by a C-program.


The students shall be able to:2.1Create a runnable program and a PCB circuit that will display an EIGHT LED lights output

controlled by a Variable resistor.2.2Apply the C-programming knowledge in embedded system programming.

3. Discussion:Variable Resistors (Pots)

Are often called 'pots' which is short for 'potentiometers'. The Serial Monitor and the pot is somehow,varying the voltage at A0 and the little test sketch is converting this voltage into a number between 0and 1023.

Figure 7-1 Variable Resistor (Pots)

Pot has a circular 'track' that acts as a resistor; in this case it is a 10 k resistor. However, the differencewith a pot is that there is also a middle connection called the 'slider'. This connection is rotated whenturning the pot. So if it is connected to one end of the pot to 5V and the other is to the GND, then thevoltage at the slider will vary between 0 and 5V.


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1. Arduino/Gizduino board2. Computer3. USB Cable4. Power Source

5.

Bread board6. 8 LED (any color)7. 10K Variable resistor (pot)8. Potentiometer9. 8 Resistors (270 )10.74HC595 Shift Register11. IC Socket12.2x2 Printed Circuit Board13.Ferric Chloride14.Plastic Container15.Permanent Marker

16.

Masking Tape17.Mini Drill18.Connecting wires

5. Procedure:

1. Create a bread board layout as shown in Figure 7-2.

Figure 7-2 Bread Board Connection


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2. Copy the program in Appendix B3. Simulate the program.4. Save file as Activity 7-1.5. Write the COM4 output at the data and results

6.

Fill-out Table 7-1.7. Create a new program as shown in Figure 7-3.

Figure 7-3 Source Code8. Fill-up Table 7-2.


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Table 7-1. Baud Rate

Case COM4 Output Observation4800 baud

14400 baud

19200 baud

28800 baud

38400 baud

57600 baud115200 baud





pinMode(clockPin,INPUT)

i--


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7. Data Analysis:



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Activity No. 8

SENSOR AND SOUNDS



Name : Instructor:

1. Objective(s):

The activity aims to create a runnable program using the Arduino programming software that will displayan EIGHT LED lights and serial monitor output controlled by a photocell electronic component. Thisactivity also provides students with knowledge and skills on how to develop a circuit using photocellelectronic component that will transmit a data through the use of C program codes.


The students shall be able to:2.1Create a runnable program that will display an Eight LED lights and serial monitor output by a

photocell electronic component.2.2Apply the C-programming knowledge in embedded system programming.

3. Discussion:

A sensor is a converter that measures aphysical quantity and converts it into a signal which can be read

by an observer or by an (today mostlyelectronic) instrument. For example, amercury-in-glassthermometer converts the measured temperature into expansion and contraction of a liquid which canbe read on a calibrated glass tube. Athermocouple converts temperature to an output voltage which canbe read by avoltmeter.For accuracy, most sensors arecalibrated against knownstandards.

Sensors are used in everyday objects such as touch-sensitive elevator buttons (tactile sensor) andlamps which dim or brighten by touching the base. There are also innumerable applications for sensorsof which most people are never aware. Applications include cars, machines, aerospace, medicine,manufacturing and robotics.

A sensor is a device, which responds to an input quantity by generating a functionally related output

usually in the form of an electrical or optical signal. A sensor's sensitivity indicates how much thesensor's output changes when the measured quantity changes. For instance, if the mercury in athermometer moves 1 cm when the temperature changes by 1 C, the sensitivity is 1 cm/C (it isbasically the slope Dy/Dx assuming a linear characteristic). Sensors that measure very small changesmust have very high sensitivities. Sensors also have an impact on what they measure; for instance, aroom temperature thermometer inserted into a hot cup of liquid cools the liquid while the liquid heats thethermometer. Sensors need to be designed to have a small effect on what is measured; making the
http://en.wikipedia.org/wiki/Physical_quantityhttp://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Mercury-in-glass_thermometerhttp://en.wikipedia.org/wiki/Mercury-in-glass_thermometerhttp://en.wikipedia.org/wiki/Thermocouplehttp://en.wikipedia.org/wiki/Voltmeterhttp://en.wikipedia.org/wiki/Calibrationhttp://en.wikipedia.org/wiki/Standard_(metrology)http://en.wikipedia.org/wiki/Tactile_sensorhttp://en.wikipedia.org/wiki/Tactile_sensorhttp://en.wikipedia.org/wiki/Standard_(metrology)http://en.wikipedia.org/wiki/Calibrationhttp://en.wikipedia.org/wiki/Voltmeterhttp://en.wikipedia.org/wiki/Thermocouplehttp://en.wikipedia.org/wiki/Mercury-in-glass_thermometerhttp://en.wikipedia.org/wiki/Mercury-in-glass_thermometerhttp://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Physical_quantity


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sensor smaller often improves this and may introduce other advantages. Technological progress allowsmore and more sensors to be manufactured on a microscopic scale as microsensorsusingMEMS technology. In most cases, a microsensor reaches a significantly higher speed andsensitivity compared withmacroscopic approaches.

A photoresistor or light-dependent resistor (LDR) or photocell is a light-controlled variableresistor.Theresistance of a photoresistor decreases with increasing incident light intensity; in other words, itexhibitsphotoconductivity.A photoresistor can be applied in light-sensitive detector circuits, and light-and dark-activated switching circuits.

A photoresistor is made of a high resistancesemiconductor. In the dark, a photoresistor can have aresistance as high as a few megaohms (M), while in the light, a photoresistor can have a resistance aslow as a few hundred ohms. If incident light on a photoresistor exceeds acertainfrequency,photons absorbed by the semiconductor give boundelectrons enough energy to jumpinto theconduction band. The resulting free electrons (and theirhole partners) conduct electricity,thereby loweringresistance.The resistance range and sensitivity of a photoresistor can substantially

differ among dissimilar devices. Moreover, unique photoresistors may react substantially differently tophotons within certain wavelength bands.

A photoelectric device can be either intrinsic or extrinsic. An intrinsic semiconductor has its ownchargecarriers and is not an efficient semiconductor, for example, silicon. In intrinsic devices the only availableelectrons are in the valence band, and hence the photon must have enough energy to excite theelectron across the entire bandgap. Extrinsic devices have impurities, also calleddopants,and addedwhose ground state energy is closer to the conduction band; since the electrons do not have as far tojump, lower energy photons (that is, longer wavelengths and lower frequencies) are sufficient to triggerthe device. If a sample of silicon has some of its atoms replaced by phosphorus atoms (impurities),there will be extra electrons available for conduction. This is an example of an extrinsic semiconductor.

SoundSound waves are vibrations in the air pressure. The speed of the vibrations (cycles per second or Hertz)is what makes the pitch of the sound. The higher the frequency of the vibration, the higher the pitch, asshown in Figure 8-1.

Figure 8-1 Piezo Sounder
http://en.wikipedia.org/wiki/Microscopic_scalehttp://en.wikipedia.org/wiki/Microelectromechanical_systemshttp://en.wikipedia.org/wiki/Macroscopichttp://en.wikipedia.org/wiki/Resistorhttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/wiki/Photoconductivityhttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Frequencyhttp://en.wikipedia.org/wiki/Photonhttp://en.wikipedia.org/wiki/Electronhttp://en.wikipedia.org/wiki/Conduction_bandhttp://en.wikipedia.org/wiki/Electron_holehttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/wiki/Charge_carrierhttp://en.wikipedia.org/wiki/Charge_carrierhttp://en.wikipedia.org/wiki/Valence_bandhttp://en.wikipedia.org/wiki/Dopantshttp://en.wikipedia.org/wiki/Dopantshttp://en.wikipedia.org/wiki/Valence_bandhttp://en.wikipedia.org/wiki/Charge_carrierhttp://en.wikipedia.org/wiki/Charge_carrierhttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/wiki/Electron_holehttp://en.wikipedia.org/wiki/Conduction_bandhttp://en.wikipedia.org/wiki/Electronhttp://en.wikipedia.org/wiki/Photonhttp://en.wikipedia.org/wiki/Frequencyhttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Photoconductivityhttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/wiki/Resistorhttp://en.wikipedia.org/wiki/Macroscopichttp://en.wikipedia.org/wiki/Microelectromechanical_systemshttp://en.wikipedia.org/wiki/Microscopic_scale


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Middle C is usually defined as a frequency of 261 Hz. If it turns a digital output on and off again 261times every second then that output will be middle C. To hear the output, it one needs to attachsomething that will convert the electrical signal into sound waves. This can be done with a loudspeakeror piezo sounder. Piezo sounders use a special crystal that expands and contracts as an electrical

signal passes through it.

Reference: http://en.wikipedia.org/wiki4. Materials and Equipment:

1. Arduino/Gizduino board2. Computer3. USB Cable4. Power Source5. Bread board6. 8 LED (any color)7. Photocell (Light Dependent Resistor)

8.

8 Resistors (270 )9. 1 Resistor (1k )10.Piezo Sounder11.74HC595 Shift Register12. IC Socket13.2x2 Printed Circuit Board14.Ferric Chloride15.Plastic Container16.Permanent Marker17.Masking Tape18.Mini Drill

19.

Connecting wires

5. Procedure:

1. Create a Breadboard connection as shown in Figure 8-2.

Figure 8-2 Breadboard Connection


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2. Remove and replace the pot by a photocell.3. Open Sketch software.4. Copy the source code at Appendix C5. Upload the program.

6.

Save the file as Activity 8-1.7. Fill-out Table 8-1.8. Design a PCB circuit for Figure 8-1.9. Draw a schematic diagram at the data and results.10.Create a PCB and Arduino/Gizduino board connection.11.Create a new breadboard circuit connection as shown in Figure 8-3.

Figure 8-3. Breadboard connection using Piezo Sounder

12.Copy the source code at Appendix D13.Upload the program.14.Save the file as Activity 8-2.15.Create a new file.16.Save the file as Activity 8-3.17.

Copy the Source code at Figure 8-4.


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Figure 8-4 Loop Sound Source Code18.Upload the program.19.Answer the question at the data and results.






pinMode(clockPin,INPUT)

i--

int lightpin= 5;

int latchpin=6;

int clockpin=4;int datapin=0;

Schematic Diagram

Is there an output sound produced by the piezo sounder? ______


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7. Data Analysis:



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Activity No. 9

LCD DISPLAY



Name : Instructor:

1. Objective(s):

The activity aims to create a runnable program using the Arduino programming software that will displayan LCD output. This activity also provides students with knowledge and skills on how to develop a circuitusing LCD display controlled by a C-program.


The students shall be able to:2.1Create a runnable program that will display an LCD output.2.2Apply the C-programming knowledge in embedded system programming.

3. Discussion:

Liquid Cristal Display (LCD)

Description

Creates a variable of type LiquidCrystal. The display can be controlled using 4 or 8 data lines. If theformer, omit the pin numbers for d0 to d3 and leave those lines unconnected. The RW pin can be tied toground instead of connected to a pin on the Arduino; if so, omit it from this function's parameters.

Syntax

LiquidCrystal(rs, enable, d4, d5, d6, d7)

LiquidCrystal(rs, rw, enable, d4, d5, d6, d7)

LiquidCrystal(rs, enable, d0, d1, d2, d3, d4, d5, d6, d7)

LiquidCrystal(rs, rw, enable, d0, d1, d2, d3, d4, d5, d6, d7)

Parameters

rs: the number of the Arduino pin that is connected to the RS pin on the LCDrw: the number of the Arduino pin that is connected to the RW pin on the LCD (optional)enable: the number of the Arduino pin that is connected to the enable pin on the LCD


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d0, d1, d2, d3, d4, d5, d6, d7: the numbers of the Arduino pins that are connected to the correspondingdata pins on the LCD. d0, d1, d2, and d3 are optional; if omitted, the LCD will be controlled using onlythe four data lines (d4, d5, d6, d7).

Example:

#include

LiquidCrystallcd(12, 11, 10, 5, 4, 3, 2);

void setup()

{lcd.begin(16,1);lcd.print("hello, world!");

}

void loop() {}


1. Arduino/Gizduino board2. Computer3. USB Cable4. Power Source5. Bread board6. LCD Display (16x2 Characters)7. 10K Variable Resistor8. 1K Resistor

9.

Photocell10.TMP36 Temperature Sensor11.Connecting wires


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5. Procedure:

1. Create a connection as shown at Figure 9-1.

Figure 9-1 LCD Breadboard Connection2. Open Sketch software.3. Copy the program at Figure 9-2.


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Figure 9-2 LCD Source Code

4. Upload the program.5. Draw the LCD output at the data and results6. Save the file as Activity 9-1.7. Write a temperature program that will compute and display an output using a unit in Celsius.8. Draw a schematic diagram for Figure 9-1.


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LCD Output

Program Source Code

Schematic Diagram


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7. Data Analysis:



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Activity No. 10

MOTORS



Name : Instructor:

1. Objective(s):

The activity aims to create a runnable program using the Arduino programming software that willproduce a motor movement output. This activity also provides students with knowledge and skills onhow to develop a circuit with motor application that is controlled by a C-program.


The students shall be able to:2.1Create a runnable program that can control a motor.2.2Apply the C-programming knowledge in embedded system programming.

3. Discussion:

Transistor and DC Motor

The small DC motor is likely to use more power than an Arduino digital output can handle directly. If it is

tried to connect the motor straight to an Arduino pin, there is a good chance that it could damage theArduino. A small transistor like the PN2222 can be used as a switch that uses just a little current fromthe Arduino digital output to control the much bigger current of the motor, as shown in Figure 10-1.

Figure 10-1 Transistor


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The transistor has three leads. Most of the electricity flows from the Collector to the Emitter, but this willonly happen if a small amount is flowing into the Base connection. This small current is supplied by theArduino digital output. The diagram below is called a schematic diagram (Figure 10-2). Like abreadboard layout, it is a way of showing how the parts of an electronic project are connected together.

Figure 10-2 Motor Connection Schematic Diagram

The pin D3 of the Arduino is connected to the resistor. Just like when using an LED, this limits thecurrent flowing into the transistor through the base. There is a diode connected across the connectionsof the motor. Diodes only allow electricity to flow in one direction (the direction of their arrow).


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Servo Motor

The position of the servo motor is set by the length of a pulse. The servo expects to receive a pulseroughly every 20 milliseconds. If that pulse is high for 1 millisecond, then the servo angle will be zero, ifit is 1.5 milliseconds, then it will be at its centre position and if it is 2 milliseconds it will be at 180degrees, as shown in Figure 10-3.

Figure 10-3 Servo Motor Cycle

The end points of the servo can vary and many servos only turn through about 170 degrees.

L293D

This is a very useful chip. It can actually control two motors independently. Most of the pins on the right

hand side of the chip are for controlling a second motor. As shown in Figure 10-4.


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Figure 10-4 L293 Pin Configuration

A second motor would be attached between OUT3 and OUT4. Three more control pins are needed tocontrol the EN2 that is connected to a PWM enabled output pin on the Arduino IN3 and IN4 areconnected to digital outputs on the Arduino. The L293D has two +V pins (8 and 16). The pin '+Vmotor(8) provides the power for the motors, and +V (16) for the chip's logic. Connect both of these to theArduino 5V pin. However, if there are more powerful motor, or a higher voltage motor, it would providethe motor with a separate power supply using pin 8 connected to the positive power supply and the


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ground of the second power supply that is connected to the ground of the Arduino.

Stepper Motor

Stepper motors use a cogged wheel and electro magnets to nudge the wheel round a 'step' at a time , as

shown in Figure 10-5.

Figure 10-5 Stepper Motor

By energizing the coils in the right order, the motor is driven round. The number of steps that the steppermotor has in a 360 degree rotation is actually the number of teeth on the cog. This motor has 48 steps,

but then the motor also incorporates a reduction gearbox of 1:16 that means that it needs 16 x 48 = 768steps. This connection is only provided if a different type of drive circuit that does not allow the current ineach coil to be reversed. Having a center connection to each coil means that it can both energize the leftor right side of the coil, and get the effect of reversing the current flow without having to use a circuit thatcan reverse the current. Since, L293D is very good at reversing the current, there no need this forcommon connection, the supply current can either direct go to the whole of each of the coils.


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4.

Power Source5. Bread board6. Connecting wires7. 1 Small 6V DC Motor8. 1 PN2222 Transistor9. 1 1N4001 diode10.1 Resistor (270)11.1 Servo Motor12.10k Variable Resistor13.1 Capacitor (100 F)14.1 L293D IC

15.

1 Tactile Push Switch16.1 5V Stepper Motor

5. Procedure:

1. Create a circuit and board connection as shown in Figure 10-6.

Figure 10-6 DC Motor Board Connection


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2. Open Sketch software.3. Copy the source code at Figure 10-7.

Figure 10-7 DC Motor Source Code


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4. Save the file as Activity 10-1.5. Compile the program.6. Write the COM4 output at the data and results.7. Reverse the connection.

8.

Compile the program.9. Write the COM4 output at the data and results.10.Create a new circuit and board connection as shown in Figure 10-8.11.Create a new program12.Copy the program at Figure 10-9.13.Save the file as Activity 10-2.14.Compile the program.15.Write the COM4 output at the data and results.16.Reverse the connection.17.Compile the program.18.Write the COM4 output at the data and results.

19.

Create a new circuit and board connection as shown in Figure 10-10.20.

Create a new program21.Copy the program at Figure 10-11.22.Save the file as Activity 10-3.23.Compile the program.24.Write the COM4 output at the data and results.25.Reverse the connection.26.Compile the program.27.Write the COM4 output at the data and results.28.Create a new circuit and board connection as shown in Figure 10-12.29.Create a new program30.Copy the program at Figure 10-13.31.

Save the file as Activity 10-4.32.Compile the program.33.Write the COM4 output at the data and results.34.Reverse the connection.35.Compile the program.36.Write the COM4 output at the data and results.


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Figure 10-8 Servo Motor Connections


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Figure 10-9A Sweep Movement Figure 10-9B Knob Movement

Figure 10-9 Servo Motor Code

Figure 10-10 DC Reverse Board Connection


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Figure 10-11 Source Code for Bi-directional Movement

Figure 10-12 Stepper Motor Board Connection


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Figure 10-13 Stepper Motor Code



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7. Data Analysis:



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Appendix


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Appendix A

/*

Shift Register Example

Turning on the outputs of a 74HC595 using an array

Hardware:

* 74HC595 shift register

* LEDs attached to each of the outputs of the shift register

*/

//Pin connected to ST_CP of 74HC595

int latchPin = 8;

//Pin connected to SH_CP of 74HC595

int clockPin = 12;

////Pin connected to DS of 74HC595int dataPin = 11;

//holders for infromation you're going to pass to shifting

function

byte data;

byte dataArray[10];

void setup() {

//set pins to output because they are addressed in the main

loop

pinMode(latchPin, OUTPUT);

Serial.begin(9600);

//Arduino doesn't seem to have a way to write binary straight

into the code

//so these values are in HEX. Decimal would have been fine,

too.

dataArray[0] = 0xFF; //11111111

dataArray[1] = 0xFE; //11111110dataArray[2] = 0xFC; //11111100

dataArray[3] = 0xF8; //11111000

dataArray[4] = 0xF0; //11110000

dataArray[5] = 0xE0; //11100000

dataArray[6] = 0xC0; //11000000


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dataArray[7] = 0x80; //10000000

dataArray[8] = 0x00; //00000000

dataArray[9] = 0xE0; //11100000

//function that blinks all the LEDs

//gets passed the number of blinks and the pause timeblinkAll_2Bytes(2,500);

}

void loop() {

for (int j = 0; j < 10; j++) {

//load the light sequence you want from array

data = dataArray[j];

//ground latchPin and hold low for as long as you are

transmitting

digitalWrite(latchPin, 0);

//move 'em out

shiftOut(dataPin, clockPin, data);

//return the latch pin high to signal chip that it

//no longer needs to listen for information


delay(300);

}

}

// the heart of the program

void shiftOut(int myDataPin, int myClockPin, byte myDataOut) {

// This shifts 8 bits out MSB first,

//on the rising edge of the clock,

//clock idles low

//internal function setupint i=0;

int pinState;

pinMode(myClockPin, OUTPUT);

pinMode(myDataPin, OUTPUT);


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//clear everything out just in case to

//prepare shift register for bit shifting

digitalWrite(myDataPin, 0);

digitalWrite(myClockPin, 0);

//for each bit in the byte myDataOut

//NOTICE THAT WE ARE COUNTING DOWN in our for loop

//This means that %00000001 or "1" will go through such

//that it will be pin Q0 that lights.

for (i=7; i>=0; i--) {

digitalWrite(myClockPin, 0);

//if the value passed to myDataOut and a bitmask result

// true then... so if we are at i=6 and our value is

// %11010100 it would the code compares it to %01000000// and proceeds to set pinState to 1.

if ( myDataOut & (1


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//has its full visual effect.

void blinkAll_2Bytes(int n, int d) {


shiftOut(dataPin, clockPin, 0);


digitalWrite(latchPin, 1);delay(200);

for (int x = 0; x < n; x++) {





delay(d);





delay(d);

}

}


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Appendix B


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Appendix C


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Appendix D


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Appendix E

List of Functions for LCD Display

1.

begin()

Description

Initializes the interface to the LCD screen, and specifies the dimensions (width and height) of the

display. begin()needs to be called before any other LCD library commands.

Syntax

lcd.begin(cols, rows)

Parameters

lcd: a variable of type LiquidCrystal

cols: the number of columns that the display has

rows: the number of rows that the display has

2.clear()

Description

Clears the LCD screen and positions the cursor in the upper-left corner.

Syntax

lcd.clear()

Parameters

lcd: a variable of typeLiquidCrystal

3.home()

Description

Positions the cursor in the upper-left of the LCD. That is, use that location in outputting subsequent

text to the display. To also clear the display, use theclear()function instead.

Syntax
http://arduino.cc/en/Reference/LiquidCrystalClearhttp://arduino.cc/en/Reference/LiquidCrystalClearhttp://arduino.cc/en/Reference/LiquidCrystalClearhttp://arduino.cc/en/Reference/LiquidCrystalClear


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lcd.home()

Parameters


4.

setCursor()

Description

Position the LCD cursor; that is, set the location at which subsequent text written to the LCD will be

displayed.

Syntax

lcd.setCursor(col, row)

Parameters


col: the column at which to position the cursor (with 0 being the first column)

row: the row at which to position the cursor (with 0 being the first row)

5.

write()

Description

Write a character to the LCD.

Syntax

lcd.write(data)

Parameters


data: the character to write to the display

Returns

byte

write()will return the number of bytes written, though reading that number is optional


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Example:

#include

LiquidCrystal lcd(12, 11, 10, 5, 4, 3, 2);

void setup()

{

Serial.begin(9600);

}

void loop()

{

if (Serial.available()) {lcd.write(Serial.read());

}

}

6.

print()

Description

Prints text to the LCD.

Syntax

lcd.print(data)

lcd.print(data, BASE)

Parameters


data: the data to print (char, byte, int, long, or string)

BASE (optional): the base in which to print numbers: BIN for binary (base 2), DEC for decimal

(base 10), OCT for octal (base 8), HEX for hexadecimal (base 16).

Returns

byte

print() will return the number of bytes written, though reading that number is optional


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Example

#include

LiquidCrystal lcd(12, 11, 10, 5, 4, 3, 2);

void setup()

{

lcd.print("hello, world!");

}

void loop() {}

7.

cursor()

Description

Display the LCD cursor: an underscore (line) at the position to which the next character will be

written.

Syntax

lcd.cursor()

Parameters


Example

cursor() and noCursor()

8.

noCursor()

Description

Hides the LCD cursor.

Syntax

lcd.noCursor()

Parameters
http://arduino.cc/en/Tutorial/LiquidCrystalCursorhttp://arduino.cc/en/Tutorial/LiquidCrystalCursor


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Example

cursor() and noCursor()

9.

blink()

Description

Display the blinking LCD cursor. If used in combination with thecursor() function, the result will

depend on the particular display.

Syntax

lcd.blink()

Parameters


Example

blink() and noBlink()

10.

noBlink()

Description

Turns off the blinking LCD cursor.

Syntax

lcd.noBlink()

Parameters


Example

blink() and noBlink()

11.

display()

Description
http://arduino.cc/en/Tutorial/LiquidCrystalCursorhttp://arduino.cc/en/Reference/LiquidCrystalCursorhttp://arduino.cc/en/Reference/LiquidCrystalCursorhttp://arduino.cc/en/Tutorial/LiquidCrystalBlinkhttp://arduino.cc/en/Tutorial/LiquidCrystalBlinkhttp://arduino.cc/en/Tutorial/LiquidCrystalBlinkhttp://arduino.cc/en/Tutorial/LiquidCrystalBlinkhttp://arduino.cc/en/Reference/LiquidCrystalCursorhttp://arduino.cc/en/Tutorial/LiquidCrystalCursor


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Turns on the LCD display, after it's been turned off withnoDisplay(). This will restore the text (and

cursor) that was on the display.
http://arduino.cc/en/Reference/LiquidCrystalNoDisplayhttp://arduino.cc/en/Reference/LiquidCrystalNoDisplayhttp://arduino.cc/en/Reference/LiquidCrystalNoDisplay


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Syntax

lcd.display()

Parameters

lcd: a variable of type LiquidCrystal

Example

display() and noDisplay()

12.noDisplay()

Description

Turns off the LCD display, without losing the text currently shown on it.

Syntax

lcd.noDisplay()

Parameters


Example

display() and noDisplay()

13.scrollDisplayLeft()

Description

Scrolls the contents of the display (text and cursor) one space to the left.

Syntax

lcd.scrollDisplayLeft()

Parameters


Example

scrollDisplayLeft() and scrollDisplayRight()
http://arduino.cc/en/Tutorial/LiquidCrystalDisplayhttp://arduino.cc/en/Tutorial/LiquidCrystalDisplayhttp://arduino.cc/en/Tutorial/LiquidCrystalScrollhttp://arduino.cc/en/Tutorial/LiquidCrystalScrollhttp://arduino.cc/en/Tutorial/LiquidCrystalDisplayhttp://arduino.cc/en/Tutorial/LiquidCrystalDisplay


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14.scrollDisplayRight()

Description

Scrolls the contents of the display (text and cursor) one space to the right.

Syntax

lcd.scrollDisplayRight()

Parameters


Example

scrollDisplayLeft() and scrollDisplayRight()15.

autoscroll()

Description

It turns ON automatic LCD scrolling. This causes each character output to the display to push

previous characters over by one space. If the current text direction is left -to-right (the default), the

display scrolls to the left; if the current direction is right-to-left, the display scrolls to the right. This

has the effect of outputting each new character to the same location on the LCD.

Syntax

lcd.autoscroll()

Parameters


16.

noAutoscroll()

Description

Turns off automatic scrolling of the LCD.

Syntax

lcd.noAutoscroll()

Parameters

http://arduino.cc/en/Tutorial/LiquidCrystalScrollhttp://arduino.cc/en/Tutorial/LiquidCrystalScroll


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17.leftToRight()

Description

Set the direction for text written to the LCD to left-to-right, the default. This means that subsequent

characters written to the display will go from left to right, but does not affect previously-output text.

Syntax

lcd.leftToRight()

Parameters


18.rightToLeft()

Description

Set the direction for text written to the LCD to right-to-left (the default is left-to-right). This means

that subsequent characters written to the display will go from right to left, but does not affect

previously-output text.

Syntax

lcd.rightToLeft()

Parameters


19.

rightToLeft()

Description

Set the direction for text written to the LCD to right-to-left (the default is left-to-right). This means

that subsequent characters written to the display will go from right to left, but does not affect

previously-output text.

Syntax

lcd.rightToLeft()

Parameters



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20.createChar()

Description

Create a custom character (gylph) for use on the LCD. Up to eight characters of 5x8 pixels are

supported (numbered 0 to 7). The appearance of each custom character is specified by an array of

eight bytes, one for each row. The five least significant bits of each byte determine the pixels in that

row. To display a custom character on the screen,write() its number.

NB : When referencing custom character "0", if it is not in a variable, you need to cast it as a byte,

otherwise the compiler throws an error. See the example below.

Syntax

lcd.createChar(num, data)

Parameters


num: which character to create (0 to 7)

data: the character's pixel data

Example

#include

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

byte smiley[8] = {

B00000,

B10001,

B00000,

B00000,

B10001,

B01110,

B00000,

};
http://arduino.cc/en/Reference/LiquidCrystalWritehttp://arduino.cc/en/Reference/LiquidCrystalWrite


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void setup() {

lcd.createChar(0, smiley);

lcd.begin(16, 2);

lcd.write(byte(0));

}

void loop() {}


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Appendix F

Sample for LCD Display

LiquidCrystal - Text Direction (leftToRight() and rightToLeft()

This example sketch shows how to use the leftToRight() and rightToLeft() methods. These methods control

which way text flows from the cursor.

rightToLeft()causes text to flow to the left from the cursor, as if the display is right-justified.

leftToRight()causes text to flow to the right from the cursor, as if the display is left-justified.

This sketch prints athrough lright to left, then mthrough rleft to right, then sthrough zright to left again.

Hardware Required

Arduino Board LCD Screen (compatible with Hitachi HD44780 driver) pin headers to solder to the LCD display pins 10k Potentiometer breadboard hook-up wire

Circuit

Before wiring the LCD screen to Arduino it is suggested to solder a pin header strip to the 14 (or 16) pin

count connector of the LCD screen, as you can see in the image above.

To wire your LCD screen to your Arduino, connect the following pins:

LCD RS pin to digital pin 12 LCD Enable pin to digital pin 11 LCD D4 pin to digital pin 5

LCD D5 pin to digital pin 4 LCD D6 pin to digital pin 3 LCD D7 pin to digital pin 2

Additionally, wire a 10K pot to +5V and GND, with its wiper (output) to LCD screens VO pin (pin3).


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Code

/*

LiquidCrystal Library - TextDirection

Demonstrates the use a 16x2 LCD display. The LiquidCrystal

library works with all LCD displays that are compatible with the


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Hitachi HD44780 driver. There are many of them out there, and you

can usually tell them by the 16-pin interface.

This sketch demonstrates how to use leftToRight() and rightToLeft()

to move the cursor.

The circuit:

* LCD RS pin to digital pin 12

* LCD Enable pin to digital pin 11

* LCD D4 pin to digital pin 5




* LCD R/W pin to ground

* 10K resistor:* ends to +5V and ground

* wiper to LCD VO pin (pin 3)

Reference:

Library originally added 18 Apr 2008 by David A. Mellis

library modified 5 Jul 2009 by Limor Fried (http://www.ladyada.net)

example added 9 Jul 2009 by Tom Igoe

modified 22 Nov 2010 by Tom Igoe

This example code is in the public domain.

http://arduino.cc/en/Tutorial/LiquidCrystalTextDirection

*/

// include the library code:

#include

// initialize the library with the numbers of the interface pins

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

int thisChar = 'a';


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void setup() {

// set up the LCD's number of columns and rows:

lcd.begin(16, 2);

// turn on the cursor:

lcd.cursor();

}

void loop() {

// reverse directions at 'm':

if (thisChar == 'm') {

// go right for the next letter

lcd.rightToLeft();

}

// reverse again at 's':

if (thisChar == 's') {

// go left for the next letter

lcd.leftToRight();

}

// reset at 'z':

if (thisChar > 'z') {

// go to (0,0):

lcd.home();

// start again at 0

thisChar = 'a';

}// print the character

lcd.write(thisChar);

// wait a second:

delay(1000);

// increment the letter:

thisChar++;

}

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