Elegoo Mega2560 User Manual

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THE MOST COMPLETE STARTER KIT

TUTORIAL FOR MEGA2560

V1.0.17.7.9

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Preface

Our Company

Established in 2011, Elegoo Inc. is a thriving technology company dedicated to opensource hardware research & development, production and marketing. Located in Shenzhen, the Silicon Valley of China, we have grown to over 150+ employees with a 10,763+ square ft. factory. Our product lines rang from DuPont wires, 2560 R3 boards to complete starter kits designed for customers of any level to learn Arduino knowledge. In addition, we also sell products of Raspberry Pi accessories like 2.8’’ TFT touch and STM32. In the future we would devote more energy and investment to 3D printer products and so on. All of our products comply with international quality standards and are greatly appreciated in a variety of different markets throughout the world.

Official website: http://www.elegoo.com US Amazon storefront: http://www.amazon.com/shops/A2WWHQ25ENKVJ1 CA Amazon storefront: http://www.amazon.ca/shops/A2WWHQ25ENKVJ1 UK Amazon storefront: http://www.amazon.co.uk/shops/A1780XYQ9DFQM6 DE Amazon storefront: http://www.amazon.de/shops/A1780XYQ9DFQM6 FR Amazon storefront: http://www.amazon.de/shops/A1780XYQ9DFQM6 ES Amazon storefront: http://www.amazon.de/shops/A1780XYQ9DFQM6 IT Amazon storefront: http://www.amazon.de/shops/A1780XYQ9DFQM6

Our Tutorial

This tutorial is designed for beginners. You will learn all the basic information about how to use Arduino controller board, sensors and components. If you want to study Arduino in more depth, we recommend that you read the Arduino Cookbook written by Michael Margolis. Some codes in this tutorial is edited by Simon Monk. Simon Monk is author of a number of books relating to Open Source Hardware. They are available in Amazon: Programming Arduino, 30 Arduino Projects for the Evil Genius and Programming the Raspberry Pi.

Customer Service

As a continuous and fast growing technology company we keep striving our best to

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offer you excellent products and quality service as to meet your expectation and you can reach out to us by simply drop a line at service@elegoo.com or

EUservice@elegoo.com. We look forward to hearing from you and any of your critical

comment or suggestion would be much valuable to us. And any of problems and questions you have with our products will be promptly replied by our experienced engineers within 12 hours (24hrs during holiday)

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Content

Lesson 0 Installing IDE ............................................................................................................. 12

Lesson 1 Add Libraries and Open Serial Monitor ................................................................... 23

Lesson 2 Blink ........................................................................................................................... 32

Lesson 3 LED ............................................................................................................................. 43

Lesson 4 RGB LED ..................................................................................................................... 50

Lesson 5 Digital Inputs ............................................................................................................. 59

Lesson 6 Active buzzer ............................................................................................................. 64

Lesson 7 Passive Buzzer ........................................................................................................... 68

Lesson 8 Tilt Ball Switch ........................................................................................................... 72

Lesson 9 Servo .......................................................................................................................... 76

Lesson 10 Ultrasonic Sensor Module ...................................................................................... 80

Lesson 11 Membrane Switch Module ..................................................................................... 85

Lesson 12 DHT11 Temperature and Humidity Sensor ............................................................ 91

Lesson 13 Analog Joystick Module .......................................................................................... 97

Lesson 14 IR Receiver Module ............................................................................................... 102

Lesson 15 MAX7219 LED Dot Matrix Module ....................................................................... 108

Lesson 16 GY-521 Module ..................................................................................................... 112

Lesson 17 HC-SR501 PIR Sensor ............................................................................................ 121

Lesson 18 Water Level Detection Sensor Module ................................................................ 131

Lesson 19 Real Time Clock Module ....................................................................................... 136

Lesson 20 Sound Sensor Module ........................................................................................... 141

Lesson 21 RC522 RFID Module .............................................................................................. 147

Lesson 22 LCD Display ............................................................................................................ 152

Lesson 23 Thermometer ........................................................................................................ 157

Lesson 24 Eight LED with 74HC595 ........................................................................................ 162

Lesson 25 The Serial Monitor ................................................................................................ 169

Lesson 26 Photocell ............................................................................................................... 175

Lesson 27 74HC595 And Segment Display ............................................................................ 180

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Lesson 28 Four Digital Seven Segment Display ..................................................................... 186

Lesson 29 DC Motors ............................................................................................................. 191

Lesson 30 Relay ...................................................................................................................... 201

Lesson 31 Stepper Motor ...................................................................................................... 206

Lesson 32 Controlling Stepper Motor With Remote ............................................................ 214

Lesson 33 Controlling Stepper Motor With Rotary Encoder ................................................ 218

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Lesson 0 Installing IDE

Introduction

The Arduino Integrated Development Environment (IDE) is the software side of the Arduino platform. In this lesson, you will learn how to setup your computer to use Arduino and how to set about the lessons that follow.

The Arduino software that you will use to program your Arduino is available for Windows, Mac and Linux. The installation process is different for all three platforms and unfortunately there is a certain amount of manual work to install the software.

STEP 1: Go to https://www.arduino.cc/en/Main/Software and find below page.

The version available at this website is usually the latest version, and the actual

version may be newer than the version in the picture.

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STEP2：Download the development software that is compatible with the operating system of your computer. Take Windows as an example here.

Click Windows Installer.

Click JUST DOWNLOAD.

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Also version 1.8.0 is available in the material we provided, and the versions of our materials are the latest versions when this course was made.

Installing Arduino (Windows)

Install Arduino with the exe. Installation package.

Click I Agree to see the following interface

Click Next

You can press Browse… to choose an installation path or directly type in the

directory you want.

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Click Install to initiate installation

Finally, the following interface appears, click Install to finish the installation.

Next, the following icon appears on the desktop

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Double-click to enter the desired development environment

You may directly choose the installation package for installation and skip the

contents below and jump to the next section. But if you want to learn some methods

other than the installation package, please continue to read the section.

Unzip the zip file downloaded, Double-click to open the program and enter the

desired development environment

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However, this installation method needs separate installation of driver.

The Arduino folder contains both the Arduino program itself and the drivers that

allow the Arduino to be connected to your computer by a USB cable. Before we

launch the Arduino software, you are going to install the USB drivers.

Plug one end of your USB cable into the Arduino and the other into a USB socket on

your computer. The power light on the LED will light up and you may get a 'Found

New Hardware' message from Windows. Ignore this message and cancel any

attempts that Windows makes to try and install drivers automatically for you.

The most reliable method of installing the USB drivers is to use the Device Manager.

This is accessed in different ways depending on your version of Windows. In

Windows 7, you first have to open the Control Panel, then select the option to view

Icons, and you should find the Device Manager in the list.

Under ‘Other Devices’, you should see an icon for ‘unknown device’ with a little

yellow warning triangle next to it. This is your Arduino.

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Right-click on the device and select the top menu option (Update Driver Software...).

You will then be prompted to either ‘Search Automatically for updated driver

software’ or ‘Browse my computer for driver software’. Select the option to browse

and navigate to the X\arduino1.8.0\drivers.

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Click 'Next' and you may get a security warning, if so, allow the software to be

installed. Once the software has been installed, you will get a confirmation message.

Windows users may skip the installation directions for Mac and Linux systems and

jump to Lesson 1. Mac and Linux users may continue to read this section.

Installing Arduino (Mac OS X)

Download and Unzip the zip file, double click the Arduino.app to enter Arduino IDE;

the system will ask you to install Java runtime library if you don’t have it in your

computer. Once the installation is complete you can run the Arduino IDE.

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Installing Arduino (Linux)

You will have to use the make install command. If you are using the Ubuntu system, it is

recommended to install Arduino IDE from the software center of Ubuntu.

TIPS: If you have problems in installing the drivers, please refer to the UNO R3,

MEGA, NANO DRIVER FAQ.

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Lesson 1 Add Libraries and Open Serial Monitor

Installing Additional Arduino Libraries

Once you are comfortable with the Arduino software and using the built-in functions,

you may want to extend the ability of your Arduino with additional libraries.

What are Libraries?

Libraries are a collection of code that makes it easy for you to connect to a sensor,

display, module, etc. For example, the built-in LiquidCrystal library makes it easy to

talk to character LCD displays. There are hundreds of additional libraries available

on the Internet for download. The built-in libraries and some of these additional

libraries are listed in the reference. To use the additional libraries, you will need to

install them.

How to Install a Library

Using the Library Manager

To install a new library into your Arduino IDE you can use the Library Manager

(available from IDE version 1.8.0). Open the IDE and click to the "Sketch" menu and

then Include Library > Manage Libraries.

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Then the library manager will open and you will find a list of libraries that are already

and wait.

installed or ready for installation. In this example we will install the Bridge library.

Scroll the list to find it, then select the version of the library you want to install.

Sometimes only one version of the library is available. If the version selection menu

does not appear, don't worry: it is normal.

There are times you have to be patient with it, just as shown in the figure. Please refresh it

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Finally click on install and wait for the IDE to install the new library. Downloading

may take time depending on your connection speed. Once it has finished,

an Installed tag should appear next to the Bridge library. You can close the library

manager.

You can now find the new library available in the Include Library menu. If you want

to add your own library open a new issue on Github.

Importing a .zip Library

Libraries are often distributed as a ZIP file or folder. The name of the folder is the

name of the library. Inside the folder will be a .cpp file, a .h file and often a

keywords.txt file, examples folder, and other files required by the library. Starting

with version 1.0.5, you can install 3rd party libraries in the IDE. Do not unzip the

downloaded library, leave it as is.

In the Arduino IDE, navigate to Sketch > Include Library. At the top of the drop down

list, select the option to "Add .ZIP Library''.

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You will be prompted to select the library you would like to add. Navigate to the .zip

file's location and open it.

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Return to the Sketch > Import Library menu. You should now see the library at the

bottom of the drop-down menu. It is ready to be used in your sketch. The zip file

will have been expanded in the libraries folder in your Arduino sketches directory.

NB: the Library will be available to use in sketches, but examples for the library will

not be exposed in the File > Examples until after the IDE has restarted.

Those two are the most common approaches. MAC and Linux systems can be

handled likewise. The manual installation to be introduced below as an alternative

may be seldom used and users with no needs may skip it.

Manual installation

To install the library, first quit the Arduino application. Then uncompress the ZIP file

containing the library. For example, if you're installing a library called

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"ArduinoParty", uncompress ArduinoParty.zip. It should contain a folder

calledArduinoParty, with files like ArduinoParty.cpp and ArduinoParty.h inside. (If

the .cpp and .h files aren't in a folder, you'll need to create one. In this case, you'd

make a folder called "ArduinoParty" and move into it all the files that were in the

ZIP file, like ArduinoParty.cpp and ArduinoParty.h.)

Drag the ArduinoParty folder into this folder (your libraries folder). Under Windows,

it will likely be called "My Documents\Arduino\libraries". For Mac users, it will likely

be called "Documents/Arduino/libraries". On Linux, it will be the "libraries" folder

in your sketchbook.

Your Arduino library folder should now look like this (on Windows):

My Documents\Arduino\libraries\ArduinoParty\ArduinoParty.cpp My Documents\Arduino\libraries\ArduinoParty\ArduinoParty.h My Documents\Arduino\libraries\ArduinoParty\examples

or like this (on Mac and Linux):

Documents/Arduino/libraries/ArduinoParty/ArduinoParty.cpp Documents/Arduino/libraries/ArduinoParty/ArduinoParty.h Documents/Arduino/libraries/ArduinoParty/examples

....

There may be more files than just the .cpp and .h files, just make sure they're all

there. (The library won't work if you put the .cpp and .h files directly into the

libraries folder or if they're nested in an extra folder. For example:

Documents\Arduino\libraries\ArduinoParty.cpp and

Documents\Arduino\libraries\ArduinoParty\ArduinoParty\ArduinoParty.cpp won't

work.)

Restart the Arduino application. Make sure the new library appears in the Sketch-

>Import Library menu item of the software. That's it! You've installed a library!

Arduino Serial Monitor (Windows, Mac, Linux)

The Arduino Integrated Development Environment (IDE) is the software side of the

Arduino platform. And, because using a terminal is such a big part of working with

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Arduinos and other microcontrollers, they decided to include a serial terminal with

the software. Within the Arduino environment, this is called the Serial Monitor.

Making a Connection

Serial monitor comes with any and all version of the Arduino IDE. To open it, simply

click the Serial Monitor icon.

Selecting which port to open in the Serial Monitor is the same as selecting a port for

uploading Arduino code. Go to Tools -> Serial Port, and select the correct port.

Tips: Choose the same COM port that you have in Device Manager.

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Once open, you should see something like this:

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Settings

The Serial Monitor has limited settings, but enough to handle most of your serial

communication needs. The first setting you can alter is the baud rate. Click on the

baud rate drop-down menu to select the correct baud rate. (9600 baud)

Last, you can set the terminal to Autoscroll or not by checking the box in the bottom

left corner.

Pros

The Serial Monitor is a great quick and easy way to establish a serial connection with

your Arduino. If you’re already working in the Arduino IDE, there’s really no need to

open up a separate terminal to display data.

Cons

The lack of settings leaves much to be desired in the Serial Monitor, and, for

advanced serial communications, it may not do the trick.

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Lesson 2 Blink

Principle

The ME

GA2560 R3

board has rows of con

nector

s along both sides that are used to

onnect to s

ever

al el

ectr

onic devices and plug-in 'shields' that extends its capability.

also has a single LED th

at y

ou can con

tro

l from your s

ketche

s. This LED is buil

onto

the

GA2560 R3

board and is often

referred t

o as the 'L' LED as this is how i

is labeled on the board.

Overview

In this lesson, you will learn how to program your MEGA2560 R3 controller board to

blink the Arduino’s built-in LED, and how to download programs by basic steps.

Component Required:

(1) x Elegoo Mega2560 R3

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You may find that your MEGA2560 R3 board's 'L' LED already blinks when you

connect it to a USB plug. This is because the boards are generally shipped with the

'Blink' sketch pre-installed.

In this lesson, we will reprogram the MEGA2560 R3 board with our own Blink sketch

and then change the rate at which it blinks.

In Lesson 0, you set up your Arduino IDE and made sure that you could find the right

serial port for it to connect to your MEGA2560 R3 board. The time has now come to

put that connection to the test and program your MEGA2560 R3 board.

The Arduino IDE includes a large collection of example sketches that you can load

up and use. This includes an example sketch for making the 'L' LED blink.

Load the 'Blink' sketch that you will find in the IDE's menu system under File >

Examples > 01.Basics

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When the sketch window opens, enlarge it so that you can see the entire sketch in

the window.

The example sketches included with the Arduino IDE are 'read-only'. That is, you can

upload them to an MEGA2560 R3 board, but if you change them, you cannot save

them as the same file.

Since we are going to change this sketch, the first thing you need to do is save your

own copy.

From the File menu on the Arduino IDE, select 'Save As..' and then save the sketch

with the name 'MyBlink'.

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You have saved your copy of 'Blink' in your sketchbook. This means that if you ever

want to find it again, you can just open it using the File > Sketchbook menu option.

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Attach your Arduino board to your computer with the USB cable and check that the

'Board Type' and 'Serial Port' are set correctly.

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Note: The Board Type and Serial Port here are not necessarily the same as shown

in picture. If you are using 2560, then you will have to choose Mega 2560 as the

Board Type, other choices can be made in the same manner. And the Serial Port

displayed for everyone is different, despite COM 26 chosen here, it could be COM3

or COM4 on your computer. A right COM port is supposed to be COMX (arduino

XXX), which is by the certification criteria.

The Arduino IDE will show you the current settings for board at the bottom of the

window.

Click on the 'Upload' button. The second button from the left on the toolbar.

If you watch the status area of the IDE, you will see a progress bar and a series of

messages. At first, it will say 'Compiling Sketch...'. This converts the sketch into a

format suitable for uploading to the board.

Next, the status will change to 'Uploading'. At this point, the LEDs on the Arduino

should start to flicker as the sketch is transferred.

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Finally, the staus will change to 'Done'.

The other message tells us that the sketch is using 928 bytes of the 32,256 bytes

available.After the 'Compiling Sketch..' stage you could get the following error

message:

It can mean that your board is not connected at all, or the drivers have not been

installed (if necessary) or that the wrong serial port is selected.

If you encounter this, go back to Lesson 0 and check your installation.

Once the upload has completed, the board should restart and start blinking.

Open the code

Note that a huge part of this sketch is composed of comments. These are not actual

program instructions; rather, they just explain how the program works. They are

there for your benefit.

Everything between /* and */ at the top of the sketch is a block comment; it explains

what the sketch is for.

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Single line comments start with // and everything up until the end of that line is

considered a comment.

The first line of code is:

int led = 13;

As the comment above it explains, this is giving a name to the pin that the LED is

attached to. This is 13 on most Arduinos, including the MEGA2560 and Leonardo.

Next, we have the 'setup' function. Again, as the comment says, this is executed

when the reset button is pressed. It is also executed whenever the board resets for

any reason, such as power first being applied to it, or after a sketch has been

uploaded.

void setup() {

// initialize the digital pin as an output.

pinMode(led, OUTPUT);

}

Every Arduino sketch must have a 'setup' function, and the place where you might

want to add instructions of your own is between the { and the }.

In this case, there is just one command there, which, as the comment states tells

the Arduino board that we are going to use the LED pin as an output.

It is also mandatory for a sketch to have a 'loop' function. Unlike the 'setup' function

that only runs once, after a reset, the 'loop' function will, after it has finished running

its commands, immediately start again.

void loop() {

digitalWrite(led, HIGH); // turn the LED on (HIGH is the voltage level) delay(1000); // wait for a second digitalWrite(led, LOW); // turn the LED off by making the voltage LOW delay(1000); // wait for a second

}

Inside the loop function, the commands first of all turn the LED pin on (HIGH), then

'delay' for 1000 milliseconds (1 second), then turn the LED pin off and pause for

another second.

You are now going to make your LED blink faster. As you might have guessed, the

key to this lies in changing the parameter in () for the 'delay' command.

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This delay period is in milliseconds, so if you want the LED to blink twice as fast,

change the value from 1000 to 500. This would then pause for half a second each

delay rather than a whole second.

Upload the sketch again and you should see the LED start to blink more quickly.

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Lesson 3 LED

Overview

In this lesson, you will learn how to change the brightness of an LED by using

different values of resistor.

Component Required:

(1) x Elegoo Mega2560 R3

(1) x 5mm red LED

(1) x 220 ohm resistor

(1) x 1k ohm resistor

(1) x 10k ohm resistor

(2) x M-M wires (Male to Male jumper wires)

Component Introduction

BREADBOARD MB-102：

A breadboard enables you to prototype circuits quickly, without having to solder

the connections. Below is an example.

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Breadboards come in various sizes and configurations. The simplest kind is just a

grid of holes in a plastic block. Inside are strips of metal that provide electrical

connection between holes in the shorter rows. Pushing the legs of two different

components into the same row joins them together electrically. A deep channel

running down the middle indicates that there is a break in connections there,

meaning, you can push a chip in with the legs at either side of the channel without

connecting them together. Some breadboards have two strips of holes running

along the long edges of the board that are separated from the main grid. These have

strips running down the length of the board inside and provide a way to connect a

common voltage. They are usually in pairs for +5 volts and ground. These strips are

referred to as rails and they enable you to connect power to many components or

points in the board.

While breadboards are great for prototyping, they have some limitations. Because

the connections are push-fit and temporary, they are not as reliable as soldered

connections. If you are having intermittent problems with a circuit, it could be due

to a poor connection on a breadboard.

LED:

LEDs make great indicator lights. They use very little electricity and they pretty much

last forever.

In this lesson, you will use perhaps the most common of all LEDs: a 5mm red LED.

5mm refers to the diameter of the LED. Other common sizes are 3mm and 10mm.

You cannot directly connect an LED to a battery or voltage source because 1) the

LED has a positive and a negative lead and will not light if placed the wrong way and

2) an LED must be used with a resistor to limit or 'choke' the amount of current

flowing through it; otherwise, it will burn out!

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If you do not use a resistor with an LED, then it may well be destroyed almost

immediately, as too much current will flow through, heating it and destroying the

'junction' where the light is produced.

There are two ways to tell which is the positive lead of the LED and which the

negative.

Firstly, the positive lead is longer.

Secondly, where the negative lead enters the body of the LED, there is a flat edge

to the case of the LED.

If you happen to have an LED that has a flat side next to the longer lead, you should

assume that the longer lead is positive.

RESISTORS:

As the name suggests, resistors resist the flow of electricity. The higher the value of

the resistor, the more it resists and the less electrical current will flow through it.

We are going to use this to control how much electricity flows through the LED and

therefore, how brightly it shines.

But first, more about resistors...

The unit of resistance is called the Ohm, which is usually shortened to Ω the Greek

letter Omega. Because an Ohm is a low value of resistance (it doesn't resist much at

all), we also denote the values of resistors in kΩ (1,000 Ω) and MΩ (1,000,000 Ω).

These are called kilo-ohms and mega-ohms.

In this lesson, we are going to use three different values of resistor: 220Ω, 1kΩ and

10kΩ. These resistors all look the same, except that they have different colored

stripes on them. These stripes tell you the value of the resistor.

The resistor color code has three colored stripes and then a gold stripe at one end.

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Unlike LEDs, resistors do not have a positive and negative lead. They can be

connected either way around.

If you find this approach method too complicated, you can read the color ring flag

on our resistors directly to determine its resistance value. Or you may use a digital

multimeter instead.

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Connection

Schematic

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Wiring diagram

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The MEGA2560 is a convenient source of 5 volts, which we will use to provide power

to the LED and the resistor. You do not need to do anything with your MEGA2560,

except to plug it into a USB cable.

With the 220 Ω resistor in place, the LED should be quite bright. If you swap out the

220 Ω resistor for the 1kΩ resistor, then the LED will appear a little dimmer. Finally,

with the 10 kΩ resistor in place, the LED will be just about visible. Pull the red jumper

lead out of the breadboard and touch it into the hole and remove it, so that it acts

like a switch. You should just be able to notice the difference.

At the moment, you have 5V going to one leg of the resistor, the other leg of the

resistor going to the positive side of the LED and the other side of the LED going to

GND. However, if we moved the resistor so that it came after the LED, as shown

below, the LED will still light.

You will probably want to put the 220Ω resistor back in place.

It does not matter which side of the LED we put the resistor, as long as it is there

somewhere

Example picture

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Overview

Lesson 4 RGB LED

RGB LEDs are a fun and easy way to add some color to your projects. Since they are

like 3 regular LEDs in one, how to use and connect them is not much different.

They come mostly in 2 versions: Common Anode or Common Cathode.

Common Anode uses 5V on the common pin, while Common Cathode connects to

ground.

As with any LED, we need to connect some resistors inline (3 total) so we can limit

the current being drawn.

In our sketch, we will start with the LED in the Red color state, then fade to Green,

then fade to Blue and finally back to the Red color. By doing this we will cycle

through most of the color that can be achieved.

Component Required:

(1) x Elegoo Mega2560 R3

(1) x 830 Tie Points Breadboard

(4) x M-M wires (Male to Male jumper wires)

(1) x RGB LED

(3) x 220 ohm resistors

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Component Introduction

RGB:

At first glance, RGB (Red, Green and Blue) LEDs look just like regular LEDs. However,

inside the usual LED package, there are actually three LEDs, one red, one green and

yes, one blue. By controlling the brightness of each of the individual LEDs you can

mix pretty much any color you want.

We mix colors the same way you would mix paint on a palette - by adjusting the

brightness of each of the three LEDs. The hard way to do this would be to use

different value resistors (or variable resistors) as we did with in Lesson 2, but that's

a lot of work! Fortunately for us, MEGA2560 R3 board has an analogWrite function

that you can use with pins marked with a ~ to output a variable amount of power to

the appropriate LEDs.

The RGB LED has four leads. There is one lead going to the positive connection of

each of the single LEDs within the package and a single lead that is connected to all

three negative sides of the LEDs.

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Here on the photographs you can see 4 electrode LED. Every separate pin for Green

or Blue or Red color is called Anode. You will always connect “+” to it. Cathode goes

to “-“ (ground). If you connect it other way round the LED will not light.

The common negative connection of the LED package is the second pin from the flat

side. It is also the longest of the four leads and will be connected to the ground.

Each LED inside the package requires its own 220Ω resistor to prevent too much

current flowing through it. The three positive leads of the LEDs (one red, one green

and one blue) are connected to MEGA2560 output pins using these resistors.

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COLOR:

The reason that you can mix any color you like by varying the quantities of red, green

and blue light is that your eye has three types of light receptor in it (red, green and

blue). Your eye and brain process the amounts of red, green and blue and convert

it into a color of the spectrum.

In a way, by using the three LEDs, we are playing a trick on the eye. This same idea

is used in TVs, where the LCD has red, green and blue color dots next to each other

making up each pixel.

If we set the brightness of all three LEDs to be the same, then the overall color of

the light will be white. If we turn off the blue LED, so that just the red and green

LEDs are the same brightness, then the light will appear yellow.

We can control the brightness of each of the red, green and blue parts of the LED

separately, making it possible to mix any color we like.

Black is not so much a color as an absence of light. Therefore, the closest we can

come to black with our LED is to turn off all three colors.

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Theory (PWM)

Pulse Width Modulation (PWM) is a technique for controlling power.

We also use it here to control the brightness of each of the LEDs.

The diagram below shows the signal from one of the PWM pins on the MEGA2560.

Roughly every 1/500 of a second, the PWM output will produce a pulse. The length

of this pulse is controlled 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 we specify a value in the analogWrite that is somewhere in between 0 and 255,

then we will produce a pulse. If the output pulse is only high for 5% of the time, then

whatever we are driving will only receive 5% of full power.

If, however, the output is at 5V for 90% of the time, then the load will get 90% of

the power delivered to it. We cannot see the LEDs turning on and off at that speed,

so to us, it just looks like the brightness is changing.

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Connection

Schematic

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Wiring diagram

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Code

After wiring, please open the program in the code folder- Lesson 4 RGB LED, and

click UPLOAD to upload the program. See Lesson 2 for details about program

uploading if there are any errors.

Our code will use FOR loops to cycle through the colors.

The first FOR loop will go from RED to GREEN.

The second FOR loop will go from GREEN to BLUE.

The last FOR loop will go from BLUE to RED.

Try the sketch out and then we will dissect it in some detail......

The sketch starts by specifying which pins are going to be used for each of the colors:

// Define Pins

#define BLUE 3

#define GREEN 5

#define RED 6

The next step is to write the 'setup' function. As we have learnt in earlier lessons,

the setup function runs just once after the Arduino has reset. In this case, all it has

to do is define the three pins we are using as being outputs.

void setup()

{

pinMode(RED, OUTPUT);

pinMode(GREEN, OUTPUT);

pinMode(BLUE, OUTPUT);

digitalWrite(RED, HIGH);

digitalWrite(GREEN, LOW);

digitalWrite(BLUE, LOW);

}

Before we take a look at the 'loop' function, let’s look at the last function in the

sketch.

The define variables

redValue = 255; // choose a value between 1 and 255 to change the color.

greenValue = 0;

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blueValue = 0;

This function takes three arguments, one for the brightness of the red, green and

blue LEDs. In each case the number will be in the range 0 to 255, where 0 means off

and 255 means maximum brightness. The function then calls 'analogWrite' to set

the brightness of each LED.

If you look at the 'loop' function you can see that we are setting the amount of red,

green and blue light that we want to display and then pausing for a second before

moving on to the next color.

#define delayTime 10 // fading time between colors

delay(delayTime);

Try adding a few colors of your own to the sketch and watch the effect on your LED.

Example picture

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Lesson 5 Digital Inputs

Overview

In this lesson, you will learn to use push buttons with digital inputs to turn an LED

on and off.

Pressing the button will turn the LED on; pressing the other button will turn the LED

off.

Component Required:

(1) x Elegoo Mega2560 R3

(1) x 830 Tie-points Breadboard

(1) x 5mm red LED

(1) x 220 ohm resistor

(2) x push switches

(7) x M-M wires (Male to Male jumper wires)

Component Introduction

PUSH SWITCHES:

Switches are really simple components. When you press a button or flip a lever, they

connect two contacts together so that electricity can flow through them.

The little tactile switches that are used in this lesson have four connections, which

can be a little confusing.

Actually, there are only really two electrical connections. Inside the switch package,

pins B and C are connected together, as are A and D.

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Connection

Schematic

Wiring diagram

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Although the bodies of the switches are square, the pins protrude from opposite

sides of the switch. This means that the pins will only be far enough apart when they

are placed correctly on the breadboard.

Remember that the LED has to have the shorter negative lead to the left.

Code

After wiring，please open program in the code folder- Lesson 5 Digital Inputs, and

press UPLOAD to upload the program. If errors are prompted, see Lesson 2 for

details about the tutorial on program upload.

Load the sketch onto your MEGA2560 board. Pressing the left button will turn the

LED on while pressing the right button will turn it off.

The first part of the sketch defines three variables for the three pins that are to be

used. The 'ledPin' is the output pin and 'buttonApin' will refer to the switch nearer

the top of the breadboard and 'buttonBpin' to the other switch.

The 'setup' function defines the ledPin as being an OUTPUT as normal, but now we

have the two inputs to deal with. In this case, we use the set the pinMode to be

'INPUT_PULLUP' like this:

pinMode(buttonApin, INPUT_PULLUP);

pinMode(buttonBpin, INPUT_PULLUP);

The pin mode of INPUT_PULLUP means that the pin is to be used as an input, but that if nothing else is connected to the input, it should be 'pulled up' to HIGH. In other words, the default value for the input is HIGH, unless it is pulled LOW by the action of pressing the button. This is why the switches are connected to GND. When a switch is pressed, it connects the input pin to GND, so that it is no longer HIGH. Since the input is normally HIGH and only goes LOW when the button is pressed, the logic is a little upside down. We will handle this in the 'loop' function.

void loop() {

if (digitalRead(buttonApin) == LOW)

{

digitalWrite(ledPin, HIGH); } if (digitalRead(buttonBpin) == LOW)

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{

digitalWrite(ledPin, LOW); }

}

In the 'loop' function there are two 'if' statements. One for each button. Each does an 'digitalRead' on the appropriate input. Remember that if the button is pressed, the corresponding input will be LOW, if button A is low, then a 'digitalWrite' on the ledPin turns it on. Similarly, if button B is pressed, a LOW is written to the ledPin.

Example picture

Lesson 6 Active buzzer

diff

erence

twee

n the two is that an active bu

zzer

has a built-in oscillating

sour

ce,

so it will

generate

a sound

when electr

ified. A passive bu

zzer

does not ha

such a source so it will not

if DC signals are us

ed;

instead, you need to us

square waves whose

fre

quency is be

tween 2K

and 5K to drive it. T

he active

buz

zer

is often more expensive than

the

passive o

ne bec

ause of multiple built-in oscillating

circ

uits.

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Overview

In this lesson, you will learn how to generate a sound with an active buzzer.

Component Required:

(1) x Elegoo Mega2560 R3

(1) x Active buzzer (2) x F-M wires (Female to Male DuPont wires)

Component Introduction

BUZZER:

Electronic buzzers are DC-powered and equipped with an integrated circuit. They are widely used in computers, printers, photocopiers, alarms, electronic toys, automotive electronic devices, telephones, timers and other electronic products for voice devices. Buzzers can be categorized as active and passive ones. Turn the pins of two buzzers face up. The one with a green circuit board is a passive buzzer, while the other enclosed with a black tape is an active one.

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Connection

Schematic

Wiring diagram

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Code

After wiring, please open the program in the code folder- Lesson 6 Making Sounds and click UPLOAD to upload the program. See Lesson 2 for details about program uploading if there are any errors.

Example picture

Lesson 7 Passive Buzzer

midrange Mi. By the buzz

er, y

ou can play a song.

should be careful not to use the ME

GA2560 R3

board analog Write () function

generate

a pulse to

the

zzer,

because the pulse output of analog Write () is

fixed (500Hz).

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Overview

In this lesson, you will learn how to use a passive buzzer. The purpose of the experiment is to generate eight different sounds, each sound lasting 0.5 seconds: from Alto Do (523Hz), Re (587Hz), Mi (659Hz), Fa (698Hz), So (784Hz), La (880Hz), Si (988Hz) to Treble Do (1047Hz).

Component Required:

(1) x Elegoo Mega2560 R3

(1) x Passive buzzer (2) x F-M wires (Female to Male DuPont wires)

Component Introduction

Passive Buzzer:

The working principle of passive buzzer is using PWM generating audio to make the air to vibrate. Appropriately changed as long as the vibration frequency, it can generate different sounds. For example, sending a pulse of 523Hz, it can generate Alto Do, pulse of 587Hz, it can generate midrange Re, pulse of 659Hz, it can produce

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Connection

Schematic

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Wiring diagram

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Wiring the buzzer connected to the MEGA2560 R3 board, the red (positive) to the pin8, black wire (negative) to the GND.

Code

After wiring, please open the program in the code folder- Lesson 7 Passive Buzzer and click UPLOAD to upload the program. See Lesson 2 for details about program uploading if there are any errors. Before you can run this, make sure that you have installed the <pitches> library or re-install it, if necessary. Otherwise, your code won't work. For details about loading the library file, see Lesson 1.

Example picture

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Lesson 8 Tilt Ball Switch

Overview

In this lesson, you will learn how to use a tilt ball switch in order to detect small angle of inclination.

Component Required:

(1) x Elegoo Mega2560 R3

(1) x Tilt Ball switch (2) x F-M wires (Female to Male DuPont wires)

Component Introduction

Tilt sensor:

Tilt sensors (tilt ball switch) allow you to detect orientation or inclination. They are small, inexpensive, low-power and easy-to-use. If used properly, they will not wear out. Their simplicity makes them popular for toys, gadgets and appliances. Sometimes, they are referred to as "mercury switches", "tilt switches" or "rolling ball sensors" for obvious reasons. They are usually made up of a cavity of some sort (cylindrical is popular, although not always) with a conductive free mass inside, such as a blob of mercury or rolling ball. One end of the cavity has two conductive elements (poles). When the sensor is oriented so that that end is downwards, the mass rolls onto the poles and shorts them, acting as a switch throw. While not as precise or flexible as a full accelerometer, tilt switches can detect motion or orientation. Another benefit is that the big ones can switch power on their own. Accelerometers, on the other hand, output digital or analog voltage that must then be analyzed using extra circuitry.

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Connection

Schematic

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Wiring diagram

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Code

After wiring, please open the program in the code folder- Lesson 8 Ball Switch and click UPLOAD to upload the program. See Lesson 2 for details about program uploading if there are any errors.

Example picture



ime

nsion : 1.26 in x 1.18 in x 0.47 in (3.2 cm x 3 cm x 1.2 cm)



ight : 4.73 oz (

134 g

)

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Overview

Lesson 9 Servo

Servo is a type of geared motor that can only rotate 180 degrees. It is controlled by sending electrical pulses from your 2560 R3 board. These pulses tell the servo what position it should move to. The Servo has three wires, of which the brown one is the ground wire and should be connected to the GND port of 2560, the red one is the power wire and should be connected to the 5v port, and the orange one is the signal wire and should be connected to the Dig #9 port.

Component Required:

(1) x Elegoo Mega2560 R3 (1) x Servo (SG90) (3) x M-M wires (Male to Male jumper wires)

Component Introduction

SG90



Universal for JR and FP connector



Cable length : 25cm



No load; Operating speed: 0.12 sec / 60 degree (4.8V), 0.10 sec / 60 degree (6.0V)



Stall torque (4.8V): 1.6kg/cm



Temperature : -30~60'C



Dead band width: 5us



Working voltage: 3.5~6V

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Connection

Schematic

223

Wiring diagram

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Code

After wiring, please open the program in the code folder- Lesson 9 Servo and click UPLOAD to upload the program. See Lesson 2 for details about program uploading if there are any errors. Before you can run this, make sure that you have installed the < Servo> library or re-install it, if necessary. Otherwise, your code won't work.

For details about loading the library file, see Lesson 1.

Example picture

In the picture, the brown wire of servo is adapted via the black M-M wires, the red one is adapted via the red M-M wires, and the orange one is adapted via the yellow M-M wires.

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Overview

Lesson 10 Ultrasonic Sensor Module

Ultrasonic sensor is great for all kind of projects that need distance measurements, avoiding obstacles as examples. The HC-SR04 is inexpensive and easy to use since we will be using a Library specifically designed for these sensor.

Component Required:

(1) x Elegoo Mega2560 R3 (1) x Ultrasonic sensor module (4) x F-M wires (Female to Male DuPont wires)

Component Introduction

Ultrasonic sensor

Ultrasonic sensor module HC-SR04 provides 2cm-400cm non-contact measurement function, the ranging accuracy can reach to 3mm. The modules includes ultrasonic transmitters, receiver and control circuit. The basic principle of work:

(1) Using IO trigger for at least 10us high level signal, (2) The Module automatically sends eight 40 kHz and detect whether there is a pulse

signal back.

(3) IF the signal back, through high level , time of high output IO duration is the time

from sending ultrasonic tore turning. Test distance = (high level time × velocity of sound (340m/s) /2 The Timing diagram is shown below. You only need to supply a short 10us pulse to the trigger input to start the ranging, and then the module will send out an 8 cycle burst of ultrasound at 40 kHz and raise its echo. The Echo is a distance object that is pulse width and the range in proportion .You can calculate the range through the time interval between sending trigger signal and receiving echo signal. Formula: us / 58 = centimeters or us / 148 =inch; or: the range = high level time * velocity (340M/S) / 2; we suggest to use over 60ms measurement cycle, in order to prevent trigger signal to the echo signal.

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Connection

Schematic

Wiring diagram

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Code

Using a Library designed for these sensors will make our code short and simple. We include the library at the beginning of our code, and then by using simple commands we can control the behavior of the sensor.

After wiring, please open the program in the code folder- Lesson 10 Ultrasonic Sensor Module and click UPLOAD to upload the program. See Lesson 2 for details about program uploading if there are any errors. Before you can run this, make sure that you have installed the < HC-SR04> library or re-install it, if necessary. Otherwise, your code won't work.

For details about loading the library file, see Lesson 1.

Example picture

Open the monitor then you can see the data as blow:

Click the Serial Monitor button to turn on the serial monitor. The basics about the serial monitor are introduced in details in Lesson 1.

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Overview

Lesson 11 Membrane Switch Module

In this project, we will go over how to integrate a keyboard with an MEGA2560 R3 board so that the MEGA2560 R3 can read the keys being pressed by a user. Keypads are used in all types of devices, including cell phones, fax machines, microwaves, ovens, door locks, etc. They're practically everywhere. Tons of electronic devices use them for user input. So knowing how to connect a keypad to a microcontroller such as an MEGA2560 R3 board is very valuable for building many different types of commercial products. At the end when all is connected properly and programmed, when a key is pressed, it shows up at the Serial Monitor on your computer. Whenever you press a key, it shows up on the Serial Monitor. For simplicity purposes, we start at simply showing the key pressed on the computer. For this project, the type of keypad we will use is a matrix keypad. This is a keypad that follows an encoding scheme that allows it to have much less output pins than there are keys. For example, the matrix keypad we are using has 16 keys (0-9, A-D, *, #), yet only 8 output pins. With a linear keypad, there would have to be 17 output pins (one for each key and a ground pin) in order to work. The matrix encoding scheme allows for less output pins and thus much less connections that have to make for the keypad to work. In this way, they are more efficient than linear keypads, being that they have less wiring.

Component Required:

(1) x Elegoo Mega2560 R3 (1) x Membrane switch module (8) x M-M wires (Male to Male jumper wires)

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Connection

Schematic

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Wiring diagram

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When connecting the pins to the MEGA2560 R3 board, we connect them to the digital output pins, D9-D2. We connect the first pin of the keypad to D9, the second pin to D8, the third pin to D7, the fourth pin to D6, the fifth pin to D5, the sixth pin to D4, the seventh pin to D3, and the eighth pin to D2. These are the connections in a table:

Code

After wiring, please open the program in the code folder- Lesson 11 Membrane Switch Module and click UPLOAD to upload the program. See Lesson 2 for details about program uploading if there are any errors. Before you can run this, make sure that you have installed the < Keypad> library or re-install it, if necessary. Otherwise, your code won't work. For details about loading the library file, see Lesson 1.

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Example picture

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With this code, once we press a key on the keypad, it should show up on the serial monitor of the Arduino software once the code is compiled and uploaded to the MEGA2560 R3 board.

Click the Serial Monitor button to turn on the serial monitor. The basics about the serial monitor are introduced in details in Lesson 1.

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Lesson 12 DHT11 Temperature and Humidity Sensor

Overview

In this tutorial we will learn how to use a DHT11 Temperature and Humidity Sensor. It’s accurate enough for most projects that need to keep track of humidity and temperature readings. Again we will be using a Library specifically designed for these sensors that will make our code short and easy to write.

Component Required:

(1) x Elegoo Mega2560 R3 (1) x DHT11 Temperature and Humidity module (3) x F-M wires (Female to Male DuPont wires)

Component Introduction

Temp and humidity sensor:

DHT11 digital temperature and humidity sensor is a composite Sensor which contains a calibrated digital signal output of the temperature and humidity. The dedicated digital modules collection technology and the temperature and humidity sensing technology are applied to ensure that the product has high reliability and

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excellent long-term stability. The sensor includes a resistive sense of wet components and a NTC temperature measurement devices, and connects with a high-performance 8-bit microcontroller. Applications: HVAC, dehumidifier, testing and inspection equipment, consumer goods, automotive, automatic control, data loggers, weather stations, home appliances, humidity regulator, medical and other humidity measurement and control.

Product parameters

Relative humidity: Resolution: 16Bit Repeatability: ±1% RH

Accuracy: At 25℃ ±5% RH

Interchangeability: fully interchangeable Response time: 1 / e (63%) of 25℃ 6s

1m / s air 6s Hysteresis: <± 0.3% RH Long-term stability: <± 0.5% RH / yr in Temperature: Resolution: 16Bit

Repeatability: ±0.2℃

Range: At 25℃ ±2℃

Response time: 1 / e (63%) 10S Electrical Characteristics Power supply: DC 3.5～5.5V

Supply Current: measurement 0.3mA standby 60μA Sampling period: more than 2 seconds Pin Description: 1, the VDD power supply 3.5～5.5V DC 2 DATA serial data, a single bus 3, NC, empty pin 4, GND ground, the negative power

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Connection

Schematic

Wiring diagram

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As you can see we only need 3 connections to the sensor, since one of the pin is not used. The connections are: Voltage, Ground and Signal which can be connected to any Pin on our MEGA2560.

Code

After wiring, please open the program in the code folder- Lesson 12 DHT11 Temperature and Humidity Sensor and click UPLOAD to upload the program. See Lesson 2 for details about program uploading if there are any errors. Before you can run this, make sure that you have installed the < SimpleDHT> library or re-install it, if necessary. Otherwise, your code won't work.

For details about the tutorial on the loading of library file, see Lesson 1.

Example picture

Upload the program then open the monitor, we can see the data as below: (It shows the temperature of the environment, we can see it is 22 degree)

Click the Serial Monitor button to turn on the serial monitor. The basics about the serial monitor are introduced in details in Lesson 1.

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Lesson 13 Analog Joystick Module

Overview

Analog joysticks are a great way to add some control in your projects. In this tutorial we will learn how to use the analog joystick module.

Component Required:

(1) x Elegoo Mega2560 R3 (1) x Joystick module (5) x F-M wires (Female to Male DuPont wires)

Component Introduction

Joystick

The module has 5 pins: VCC, Ground, X, Y, Key. Note that the labels on yours may be slightly different, depending on where you got the module from. The thumb stick is analog and should provide more accurate readings than simple ‘directional’ joysticks tact use some forms of buttons, or mechanical switches. Additionally, you can press the joystick down (rather hard on mine) to activate a ‘press to select’ push- button. We have to use analog Arduino pins to read the data from the X/Y pins, and a digital pin to read the button. The Key pin is connected to ground, when the joystick is pressed down, and is floating otherwise. To get stable readings from the Key /Select pin, it needs to be connected to VCC via a pull-up resistor. The built in resistors on the Arduino digital pins can be used. For a tutorial on how to activate the pull-up resistors for Arduino pins, configured as inputs

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Connection

Schematic

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Wiring diagram

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We need 5 connections to the joystick. The connections are: Key, Y, X, Voltage and Ground. “Y and X” are Analog and “Key” is Digital. If you don’t need the switch then you can use only 4 pins.

Code

After wiring, please open the program in the code folder- Lesson 13 Analog Joystick Module and click UPLOAD to upload the program. See Lesson 2 for details about program uploading if there are any errors.

Analog joysticks are basically potentiometers so they return analog values. When the joystick is in the resting position or middle, it should return a value of about 512. The range of values goes from 0 to 1024.

Example picture

Elegoo Mega2560 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual