Arduino MEGA 2560 Hardware Manual Web Links

On this page are web links from the Arduino MEGA 2560 Hardware Manual for easy access to referenced websites. Find the main Arduino website at

Newer Book Available

The Arduino MEGA 2560 Hardware Manual has been replaced by the newer full color revised and updated Ultimate Arduino MEGA 2560 Hardware Manual. This page has been left to support those readers who bought the older book, which is no longer available.

Scroll down to find the chapter and section that contains the link that you are looking for, or use the links directly below to jump to the desired chapter on this page.

Chapter 1 | Chapter 2 | Chapter 3 | Chapter 4 | Chapter 5 | Chapter 6 | Chapter 7 | Chapter 8 | Chapter 9

Chapter 1

1.1.3 Uses of the Arduino MEGA 2560

Wiring project

Arduino Project Hub ICSP Header

Those readers interested in learning the C language to program Arduino boards may be interested in the book C Programming with Arduino ISBN 978-1-907920-46-2

1.1.5 Programming

The Arduino IDE is free to download from Prototype Shields

Figure 1.8 on the next page shows the Arduino MEGA PROTO shield REV3 that has the product code A000080 (

Prototype shields with the Arduino Uno form factor are also available, such as the PROTO Shield REV3, product code TSX00083 ( Custom PCB

KiCad ( is an open-source EDA (Electronic Design Automation) software package that can be used to draw circuit diagrams and lay out PCBs.

1.1.7 Open-Source and Licensing

See for more information on the various Creative Commons licenses.

For more details, see the page on the Arduino website.

1.1.8 Third Party Compatible Boards

For more information on the various spin-off boards including official boards, clones, derivatives, compatibles and even counterfeits, see the article on the Arduino blog.

1.1.9 Build Quality, Warranty and Safety

A full list of official Arduino boards can be found at on the Arduino website.

For more information on Arduino board compliance and for the warranty statement, see

1.2.1 USB Bridge Firmware

The ATmega16U2 microcontroller and its firmware replaces the FT232RL USB to UART bridge chip from FTDI ( found on the original Arduino MEGA before the Arduino MEGA 2560.

1.6.1 Installing Software

Help documentation on installing the Arduino IDE software is available for Windows, MAC OS X and Linux. Follow the links below for your operating system. Windows MAC OS X Linux

1.6.2 Getting Started, Examples and Reference

Getting started guides, examples and a software reference are all available on the Arduino website. Getting started guides and examples are a great way for new Arduino users to learn about building projects with Arduino and learning to write sketches. Getting Started Guides

Links to getting started guides for any Arduino board can be found at:

Arduino MEGA 2560 specific getting started guide: Arduino Examples and Tutorials

An index to tutorials and examples at on the Arduino website provides links to various categories. Building Breadboard Circuits

A tutorial series at shows how to build breadboard circuits with some Arduino examples. Arduino Software Reference

Arduino language and library reference:

1.6.3 Getting Help

Find the Arduino FAQ (Frequently Asked Questions) at Update: replaced by

Problems and solutions can be found on the Arduino Troubleshooting page at Update: replaced by

The Arduino wiki at is a user contributed collection of documentation and other useful information.

The Arduino Forum at is a place where anyone can post a question that will be answered by community members. The forum can also be searched for other user’s questions which may already have answers. It is also a place where more experienced Arduino users can help others by answering questions.

1.6.4 Related Open-Source Projects Fritzing

Fritzing, found at on the web, provide a software package that can be used to draw Arduino breadboard circuits and then turn them into custom made printed circuit boards or PCBs. Wiring

Find the Wiring project at on the web. Processing

Processing, found at on the web, is a programming language based on Java, and a software package for developing applications on a computer.


Find the PhysicalPixel tutorial on the Arduino website at

1.6.5 Arduino MEGA 2560 on the Web

Find the Arduino MEGA 2560 web page at which includes basic technical information and links to the circuit diagram (schematic) and board build files in electronic format.

1.7.1 Arduino DUE vs. Arduino MEGA 2560

More information on the Arduino DUE can be found at

1.7.2 Arduino MEGA ADK vs. Arduino MEGA 2560

For more information on the Arduino MEGA ADK, see

Chapter 2

2.2 Atmel, Microchip and AVR

Microchip ( EEPROM Programming is the library reference for using the EEPROM in sketches. SD Cards (SPI Interface) contains more information from Arduino on using SD cards.

See for more information on the Arduino SD card library. SPI Devices

See the library reference for more information on the SPI library. TWI and I²C Devices

See the library reference for more information on the Wire library. Analog In Example Sketch

The corresponding tutorial page for the AnalogReadSerial example sketch can be found at on the Arduino website, which shows how to connect a potentiometer to A0 to vary the voltage on this pin.

2.7.6 AREF Pin

For more information on the analogReference() function, see

2.8.3 ATmega16u2 ICSP Header

More information on DFU programming can be found on the Arduino website at and in section 5.1 of chapter 5 of this book.

2.8.4 ICSP Programming Resources

The links that follow provide more information on the Atmel-ICE, Atmel Studio and C programming of Arduino boards using Atmel Studio. Also see chapter 5. Links to older Atmel/Microchip programmers that are now redundant are also listed for interest.

Atmel-ICE –

Atmel Studio – Update: Atmel Studio has been replaced by Microchip Studio Old versions of Atmel Studio can be found at

C Programming –

Redundant no longer for sale programmers:



2.8.5 Using an Arduino as an In-System Programmer

Find more information on the Arduino website at

Chapter 3

3.2.2 ATmega2560 Alternate Pin Functions

More information on each pin function can be found in the ATmega2560 datasheet from the page on the Microchip website. Pins as Outputs
Switching Heavier Loads with Transistors and Relays

For more details on interfacing Arduino boards and microcontrollers, refer to the appropriate texts or other sources such as the Interfacing With Hardware page in the playground area on the Arduino website. Pins as Inputs
Pull-down Resistor

Find the tutorial page at on the Arduino website.

3.3.2 PWM Pins

( Taken from: )

3.3.3 Analog Pins

Refer to for information on using the analogRead() function to read values from the analog input pins. Accessing TWI Devices in Software

Use the Wire library in a sketch to access TWI bus devices by including the Wire.h header file in a sketch, and using the Wire library object and functions found in the reference on the Arduino website. Accessing SPI Devices in Software

Use the SPI object and functions from – the SPI reference page on the Arduino website. Accessing SD Cards in Software

Go to to find the SD card reference on the Arduino website. Hardware Serial Port
Using Serial Port 1, Serial Port 2 and Serial Port 3

Basic Breakout ( Again, TX and RX are crossed, and GND is connected between the Arduino and adapter boards.

Click the download link on the Tera Term home page at which will take you to a page with a link to the latest version of Tera Term.

Serial Port Reference

Go to for the serial port library reference. Software Serial Port

Go to on the Arduino website for more information on the SoftwareSerial library.

3.3.10 AREF Pin

The Arduino documentation at gives the input voltage range of the AREF pin as 0V to 5V, however the ATmega2560 datasheet gives the AREF voltage range as 1V to 5V.

3.8 Finding the Datasheets

3.8.1 ATmega2560 Datasheet

Find the ATmega2560 datasheet at on the Microchip website.

3.8.2 ATmega16U2 Datasheet

Go to to find the datasheet for the ATmega16U2 microcontroller used as the USB to serial bridge chip on Arduino MEGA 2560 boards.

Chapter 4

4.1.1 Operating Voltage

STMicroelectronics (

ON Semiconductor (

Diodes Incorporated (

Chapter 5

5.1 Updating the USB to Serial Bridge Firmware using DFU

For Windows computers, download the FLIP (Flexible In-system Programmer) software from Microchip at

For additional information on Arduino DFU programming and for DFU programming using Linux and Mac, see on the Arduino website.

5.2 Atmel Studio

Find more information about the Atmel-ICE on the Microchip website at:

To install Atmel Studio, go to on the Microchip website. Update: Microchip Studio has replaced Atmel Studio. Find older versions of Atmel Studio if needed.

Update: Find older versions of Atmel Studio here:


Go to for instructions with screen captures that shows how to install Atmel Studio in detail.

5.3.2 DFU Bootloader Firmware

At GitHub is the link to the same source code.

5.3.3 USB to Serial Bridge Firmware

The same source code and HEX files can be found on GitHub at which contains the latest version of this code and HEX files.

5.4.2 Bootloader Firmware – stk500v2

The same files can be found at on GitHub.

5.5 The RESET-EN Solder Jumper

For the Atmel-ICE, this information can be found in the Atmel-ICE User Guide that is available for download from the Microchip website at

5.6 Alternative Firmware Programming Methods

Using an Arduino as an ISP (In-system programmer) is described on the Arduino website at

Refer to for additional information on DFU programming the ATmega16u2.

Chapter 6

6.4 Getting an Electronic Copy of the Circuit Diagram

Find the circuit diagram in PDF format, and the circuit diagram and PCB design file in Eagle format at for the Arduino MEGA 2560. Look under the DOCUMENTATION tab for these files.

To view the files in Eagle format, the Eagle EDA software package will need to be downloaded from and installed.

Chapter 7

7.4 Waveform Patterns and Measurement

PicoScope 2000 series digital PC oscilloscope, model number 2205A used for oscilloscope measurements.

Chapter 8

8.8 Drill Template and KiCad Template

The drill template file as well as the KiCad template file can be found on the Resources page of this website.

The KiCad software package can be found at where it can be downloaded free of charge and unrestricted.

Chapter 9

9.5.2 Ethernet Shield Example

Information on this shield can be found at: