Skip to main content

Latest Post

What is Industry 4.0?

  What is Industry 4.0 and what are some of the technologies that are driving it? Industry 4.0 is a term that refers to the fourth industrial revolution, which is characterized by the integration of digital technologies, such as artificial intelligence, cloud computing, big data, the internet of things, robotics, and 3D printing, into the manufacturing sector. Industry 4.0 aims to create smart factories that are more efficient, flexible, and responsive to customer needs and market changes. Some of the technologies that are enabling Industry 4.0 are: - Artificial intelligence (AI) : AI is the ability of machines to perform tasks that normally require human intelligence, such as reasoning, learning, decision-making, and problem-solving. AI can help optimize production processes, improve product quality, reduce costs, and enhance customer satisfaction. - Cloud computing: Cloud computing is delivering computing services, such as servers, storage, databases, software, and analytics, ov...

Arduino Mega 2560 Datasheet

Overview

The Arduino Mega 2560 is a microcontroller board based on the ATmega2560. It has 54 digital input/output pins (of which 15 can be used as PWM outputs), 16 analog inputs, 4 UARTs (hardware serial ports), a 16 MHz crystal oscillator, a USB connection, a power jack, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started. The Mega 2560 board is compatible with most shields designed for the Uno and the former boards Duemilanove or Diecimila.

The Mega 2560 is an update to the Arduino Mega, which it replaces.

Tech specs

MICROCONTROLLERATmega2560
OPERATING VOLTAGE5V
INPUT VOLTAGE (RECOMMENDED)7-12V
INPUT VOLTAGE (LIMIT)6-20V
DIGITAL I/O PINS54 (of which 15 provide PWM output)
ANALOG INPUT PINS16
DC CURRENT PER I/O PIN20 mA
DC CURRENT FOR 3.3V PIN50 mA
FLASH MEMORY256 KB of which 8 KB used by bootloader
SRAM8 KB
EEPROM4 KB
CLOCK SPEED16 MHz
LED_BUILTIN13
LENGTH101.52 mm
WIDTH53.3 mm
WEIGHT37 g

Pinout Diagram

Warnings

The Mega 2560 has a resettable polyfuse that protects your computer's USB ports from shorts and overcurrent. Although most computers provide their own internal protection, the fuse provides an extra layer of protection. If more than 500 mA is applied to the USB port, the fuse will automatically break the connection until the short or overload is removed.

Power

The Mega 2560 can be powered via the USB connection or with an external power supply. The power source is selected automatically.

External (non-USB) power can come either from an AC-to-DC adapter (wall-wart) or battery. The adapter can be connected by plugging a 2.1mm center-positive plug into the board's power jack. Leads from a battery can be inserted in the GND and Vin pin headers of the POWER connector.

The board can operate on an external supply of 6 to 20 volts. If supplied with less than 7V, however, the 5V pin may supply less than five volts and the board may become unstable. If using more than 12V, the voltage regulator may overheat and damage the board. The recommended range is 7 to 12 volts.

The power pins are as follows:

  • Vin. The input voltage to the board when it's using an external power source (as opposed to 5 volts from the USB connection or other regulated power source). You can supply voltage through this pin, or, if supplying voltage via the power jack, access it through this pin.
  • 5V. This pin outputs a regulated 5V from the regulator on the board. The board can be supplied with power either from the DC power jack (7 - 12V), the USB connector (5V), or the VIN pin of the board (7-12V). Supplying voltage via the 5V or 3.3V pins bypasses the regulator, and can damage your board. We don't advise it.
  • 3V3. A 3.3 volt supply generated by the on-board regulator. Maximum current draw is 50 mA.
  • GND. Ground pins.
  • IOREF. This pin on the board provides the voltage reference with which the microcontroller operates. A properly configured shield can read the IOREF pin voltage and select the appropriate power source or enable voltage translators on the outputs for working with the 5V or 3.3V.

Memory

The ATmega2560 has 256 KB of flash memory for storing code (of which 8 KB is used for the bootloader), 8 KB of SRAM and 4 KB of EEPROM (which can be read and written with the EEPROM library).

Input and Output

See the mapping between Arduino pins and Atmega2560 ports:

Each of the 54 digital pins on the Mega can be used as an input or output, using pinMode(),digitalWrite(), and digitalRead() functions. They operate at 5 volts. Each pin can provide or receive 20 mA as recommended operating condition and has an internal pull-up resistor (disconnected by default) of 20-50 k ohm. A maximum of 40mA is the value that must not be exceeded to avoid permanent damage to the microcontroller.

In addition, some pins have specialized functions:

  • Serial: 0 (RX) and 1 (TX); Serial 1: 19 (RX) and 18 (TX); Serial 2: 17 (RX) and 16 (TX); Serial 3: 15 (RX) and 14 (TX). Used to receive (RX) and transmit (TX) TTL serial data. Pins 0 and 1 are also connected to the corresponding pins of the ATmega16U2 USB-to-TTL Serial chip.
  • External Interrupts: 2 (interrupt 0), 3 (interrupt 1), 18 (interrupt 5), 19 (interrupt 4), 20 (interrupt 3), and 21 (interrupt 2). These pins can be configured to trigger an interrupt on a low level, a rising or falling edge, or a change in level. See the attachInterrupt() function for details.
  • PWM: 2 to 13 and 44 to 46. Provide 8-bit PWM output with the analogWrite() function.
  • SPI: 50 (MISO), 51 (MOSI), 52 (SCK), 53 (SS). These pins support SPI communication using theSPI library. The SPI pins are also broken out on the ICSP header, which is physically compatible with the Arduino /Genuino Uno and the old Duemilanove and Diecimila Arduino boards.
  • LED: 13. There is a built-in LED connected to digital pin 13. When the pin is HIGH value, the LED is on, when the pin is LOW, it's off.
  • TWI: 20 (SDA) and 21 (SCL). Support TWI communication using the Wire library. Note that these pins are not in the same location as the TWI pins on the old Duemilanove or Diecimila Arduino boards.

See also the mapping Arduino Mega 2560 PIN diagram.

The Mega 2560 has 16 analog inputs, each of which provide 10 bits of resolution (i.e. 1024 different values). By default they measure from ground to 5 volts, though is it possible to change the upper end of their range using the AREF pin and analogReference() function.
There are a couple of other pins on the board:

  • AREF. Reference voltage for the analog inputs. Used with analogReference().
  • Reset. Bring this line LOW to reset the microcontroller. Typically used to add a reset button to shields which block the one on the board.

Communication

The Mega 2560 board has a number of facilities for communicating with a computer, another board, or other microcontrollers. The ATmega2560 provides four hardware UARTs for TTL (5V) serial communication. An ATmega16U2 (ATmega 8U2 on the revision 1 and revision 2 boards) on the board channels one of these over USB and provides a virtual com port to software on the computer (Windows machines will need a .inf file, but OSX and Linux machines will recognize the board as a COM port automatically. The Arduino Software (IDE) includes a serial monitor which allows simple textual data to be sent to and from the board. The RX and TX LEDs on the board will flash when data is being transmitted via the ATmega8U2/ATmega16U2 chip and USB connection to the computer (but not for serial communication on pins 0 and 1).

SoftwareSerial library allows for serial communication on any of the Mega 2560's digital pins.

The Mega 2560 also supports TWI and SPI communication. The Arduino Software (IDE) includes a Wire library to simplify use of the TWI bus; see the documentation for details. For SPI communication, use the SPI library.

Physical Characteristics and Shield Compatibility

The maximum length and width of the Mega 2560 PCB are 4 and 2.1 inches respectively, with the USB connector and power jack extending beyond the former dimension. Three screw holes allow the board to be attached to a surface or case. Note that the distance between digital pins 7 and 8 is 160 mil (0.16"), not an even multiple of the 100 mil spacing of the other pins.

The Mega 2560 is designed to be compatible with most shields designed for the Uno and the older Diecimila or Duemilanove Arduino boards. Digital pins 0 to 13 (and the adjacent AREF and GND pins), analog inputs 0 to 5, the power header, and ICSP header are all in equivalent locations. Furthermore, the main UART (serial port) is located on the same pins (0 and 1), as are external interrupts 0 and 1 (pins 2 and 3 respectively). SPI is available through the ICSP header on both the Mega 2560 and Duemilanove / Diecimila boards. Please note that I2C is not located on the same pins on the Mega 2560 board (20 and 21) as the Duemilanove / Diecimila boards (analog inputs 4 and 5).

Automatic (Software) Reset

Rather then requiring a physical press of the reset button before an upload, the Mega 2560 is designed in a way that allows it to be reset by software running on a connected computer. One of the hardware flow control lines (DTR) of the ATmega8U2 is connected to the reset line of the ATmega2560 via a 100 nanofarad capacitor. When this line is asserted (taken low), the reset line drops long enough to reset the chip. The Arduino Software (IDE) uses this capability to allow you to upload code by simply pressing the upload button in the Arduino environment. This means that the bootloader can have a shorter timeout, as the lowering of DTR can be well-coordinated with the start of the upload.

This setup has other implications. When the Mega 2560 board is connected to either a computer running Mac OS X or Linux, it resets each time a connection is made to it from software (via USB). For the following half-second or so, the bootloader is running on the ATMega2560. While it is programmed to ignore malformed data (i.e. anything besides an upload of new code), it will intercept the first few bytes of data sent to the board after a connection is opened. If a sketch running on the board receives one-time configuration or other data when it first starts, make sure that the software with which it communicates waits a second after opening the connection and before sending this data.

The Mega 2560 board contains a trace that can be cut to disable the auto-reset. The pads on either side of the trace can be soldered together to re-enable it. It's labeled "RESET-EN". You may also be able to disable the auto-reset by connecting a 110 ohm resistor from 5V to the reset line; see this forum thread for details.

Revisions

The Mega 2560 does not use the FTDI USB-to-serial driver chip used in past designs. Instead, it features the ATmega16U2 (ATmega8U2 in the revision 1 and revision 2 Arduino boards) programmed as a USB-to-serial converter.
Revision 2 of the Mega 2560 board has a resistor pulling the 8U2 HWB line to ground, making it easier to put into DFU mode.
Revision 3 of the Arduino board and the current Genuino Mega 2560 have the following improved features:

  • 1.0 pinout: SDA and SCL pins - near to the AREF pin - and two other new pins placed near to the RESET pin, the IOREF that allow the shields to adapt to the voltage provided from the board. In future, shields will be compatible both with the board that use the AVR, which operate with 5V and with the board that uses ATSAM3X8E, that operate with 3.3V. The second one is a not connected pin, that is reserved for future purposes.
  • Stronger RESET circuit.
  • Atmega 16U2 replace the 8U2.


Comments

Popular

Playing with Buttons

Button Pushbuttons or switches connect two points in a circuit when you press them. This example turns on the built-in LED on pin 13 when you press the button. Hardware Arduino Board Momentary button or Switch 10K ohm resistor hook-up wires breadboard Circuit diagram Code // constants won't change. They're used here to // set pin numbers: const int buttonPin = 2 ;     // the number of the pushbutton pin const int ledPin =   13 ;      // the number of the LED pin // variables will change: int buttonState = 0 ;         // variable for reading the pushbutton status void setup () {   Serial . begin ( 9600 );   // initialize the LED pin as an output:   pinMode (ledPin, OUTPUT);   // initialize the pushbutton pin as an input:   pinMode (buttonPin, INPUT); } void loop () {   // read the state of the pushbutton value:   buttonState = digitalRead (buttonPin);   // Show the state of pushbutton on s...

Home Automation

A smart system made by using Node MCU dev board. What is Node MCU? NodeMCU is an open-source firmware for which open-source prototyping board designs are available. The name "NodeMCU" combines "node" and "MCU" (micro-controller unit). The term "NodeMCU" strictly speaking refers to the firmware rather than the associated development kits.  Both the firmware and prototyping board designs are open source. Requirments Node MCU 4 channel relay toggle switch * 4 Hi-links (220v ac to 5v dc) Circuit Diagram Program #ifdef ENABLE_DEBUG         #define DEBUG_ESP_PORT Serial         #define NODEBUG_WEBSOCKETS         #define NDEBUG #endif #include <Arduino.h> #include <ESP8266WiFi.h> #include "SinricPro.h" #include "SinricProSwitch.h" #include <map> #define WIFI_SSID         "your wifi name"     #define WIFI_PASS         "your wifi pass" #define APP_KEY...

Turn LED On and Off Through LDR

  LDR An LDR ( Light Dependent Resistor ) is a component that has a (variable) resistance that changes with the light intensity that falls upon it. This allows them to be used in light sensing circuits. A photoresistor is made of a high resistance semiconductor. Hardware Required Arduino Board LED 220 ohm resistor LDR 10k ohms resistor Circuit Diagram Code int ldr=A0; //Set A0(Analog Input) for LDR. int value= 0 ; void setup () { Serial . begin ( 9600 ); pinMode ( 3 ,OUTPUT); } void loop () { value= analogRead (ldr); //Reads the Value of LDR(light). Serial . println ( "LDR value is :" ); //Prints the value of LDR to Serial Monitor. Serial . println (value); if (value< 300 )   {     digitalWrite ( 3 ,HIGH); //Makes the LED glow in Dark.   }   else   {     digitalWrite ( 3 ,LOW); //Turns the LED OFF in Light.   } }

Temperature sensor

About the LM35 The LM35 is an inexpensive, precision Centigrade temperature sensor made by  Texas Instruments . It provides an output voltage that is linearly proportional to the Centigrade temperature and is, therefore, very easy to use with the Arduino. The sensor does not require any external calibration or trimming to provide accuracies of ±0.5°C at room temperature and ±1°C over the −50°C to +155°C temperature range. One of the downsides of the sensor is that it requires a negative bias voltage to read negative temperatures. So if that is needed for your project, I recommend using the DS18B20 or TMP36 instead. The TMP36 by Analog Devices is very similar to the LM35 and can read temperatures from -40°C to 125°C without any external components Note that the sensor operates on a voltage range of 4 to 30 V and that the output voltage is independent of the supply voltage. The LM35 is part of a series of analog temperature sensors sold by Texas Instruments. Other members of the seri...

MQ2 Gas Sensor

 About Gas Sensor The MQ series of gas sensors use a small heater inside with an electrochemical sensor. They are sensitive to a range of gasses and are used indoors at room temperature. The output is an analog signal and can be read with an analog input of the Arduino. The MQ-2 Gas Sensor module is useful for gas leakage detection in homes and industries. It can detect LPG, i-butane, propane, methane, alcohol, hydrogen, and smoke. Some modules have a built-in variable resistor to adjust the sensitivity of the sensor. Note:  The sensor becomes very hot after a while, don't touch it! Required  Arduino UNO Breadboard MQ-2 Gas sensor module Red, Green led 5mm 220 Ohm Buzzer The connections are pretty easy: The MQ-5 sensor Pin-> Wiring to Arduino Uno A0-> Analog pins D0-> none GND-> GND VCC-> 5V other components Pin-> Wiring to Arduino Uno D13-> +ve of buzzer GND-> -ve of buzzer D12-> anode of red light D11-> anode of green light GND-> cathode...

Play a melody with a Piezo speaker

  Play a Melody using the tone() function This example shows how to use the  tone()  command to generate notes. It plays a little melody you may have heard before. Hardware Required Arduino board piezo buzzer or a speaker hook-up wires Making header file To make the pitches.h file, either click on the button just below the serial monitor icon and choose "New Tab", or use Ctrl+Shift+N. Then paste in the following code: /************************************************* * Public Constants *************************************************/ # define NOTE_B0 31 # define NOTE_C1 33 # define NOTE_CS1 35 # define NOTE_D1 37 # define NOTE_DS1 39 # define NOTE_E1 41 # define NOTE_F1 44 # define NOTE_FS1 46 # define NOTE_G1 49 # define NOTE_GS1 52 # define NOTE_A1 55 # define NOTE_AS1 58 # define NOTE_B1 62 # define NOTE_C2 65 # define NOTE_CS2 69 # define NOTE_D2 73 # define NOTE_DS2 78 # define NOTE_E2 82 # define NOTE_F2 87 ...

Seven Segment Display Interfacing with Arduino

Seven-Segment Introduction  Let’s start the main part of this tutorial by answering a question: what is a seven-segment display? As its name suggests, a 7-segment device consists of 7  light-emitting diodes . These light-emitting diodes are arranged and packed inside a single display with a specific pattern in mind. If this pattern is controlled in a specific way by turning on and turning off LEDs, a seven-segment device will display a unique number. There is also an extra eighth LED on a seven-segment display which is used to display dots. This dot is sometimes used as a decimal point when we want to display a fractional value.  The picture below shows a seven-segment display and its pinout. The string of eight LEDs on the left side shows the internal connection and a picture on the right side shows how these LEDs are arranged to make a seven-segment display. Pin3 and 8 are common pins. These pins are used to provide either 5 volts or ground in common-anode and common ca...

Mini Oscilloscope via Arduino Nano

What is an oscilloscope?   An  oscilloscope , formerly known as an oscillograph, is an instrument that graphically displays electrical signals and shows how those signals change over time. It measures these signals by connecting with a sensor, which is a device that creates an electrical signal in response to physical stimuli like sound, light, and heat. For instance, a microphone is a sensor that converts sound into an electrical signal. Oscilloscopes are often used when designing, manufacturing, or repairing electronic equipment. Engineers use an oscilloscope to measure electrical phenomena and solve measurement challenges quickly and accurately to verify their designs or confirm that a sensor is working properly. Scientists, engineers, physicists, repair technicians, and educators use oscilloscopes to see signals change over time. An automotive engineer might use an oscilloscope to correlate analog data from sensors with serial data from the engine control unit. Meanwh...

Fade an LED

  Fade This example demonstrates the use of the  analogWrite()  function in fading an LED off and on. AnalogWrite uses  pulse width modulation (PWM) , turning a digital pin on and off very quickly with different ratio between on and off, to create a fading effect. Hardware Required Arduino board LED 220 ohm resistor hook-up wires Circuit Diagram Code int led = 9 ;           // the PWM pin the LED is attached to int brightness = 0 ;    // how bright the LED is int fadeAmount = 5 ;    // how many points to fade the LED by // the setup routine runs once when you press reset: void setup () {   // declare pin 9 to be an output:   pinMode (led, OUTPUT); } // the loop routine runs over and over again forever: void loop () {   // set the brightness of pin 9:   analogWrite (led, brightness);   // change the brightness for next time through the loop:   brightness = brightness + fadeAmount; ...

Fire Alarm with arduino

Flame Sensor A  flame detector  is a sensor designed to detect and respond to the presence of a flame or fire. Responses to a detected flame depend on the installation but can include sounding an alarm, deactivating a fuel line (such as a propane or a natural gas line), and activating a fire suppression system. The IR Flame sensor used in this project is shown below, these sensors are also called  Fire sensor modules  or  flame detector sensors  sometimes. There are different types of flame detection methods. Some of them are Ultraviolet detector, near IR array detector, infrared (IR) detector, Infrared thermal cameras, UV/IR detector, etc. When fire burns it emits a small amount of Infra-red light, this light will be received by the Photodiode (IR receiver) on the sensor module. Then we use an Op-Amp to check for a change in voltage across the IR Receiver, so that if a fire is detected the output pin (DO) will give 0V(LOW), and if the is no fire the o...