Geekduino Mega Olympic(2560)
Quad-Core Arduino? No, It is Geekduino MEGA Olympic! The Geekduino Mega Olympic is a microcontroller board based on the ATmega2560 (datasheet). It has 54 digital input/output pins (of which 14 can be used as PWM outputs), 16 analog inputs, 4 UARTs (hardware serial ports), a 16 MHz crystal oscillator, a microUSB connector, a power jack, three ICSP headers(one for Atmega16u2,the other two for ATmega2560 ), and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a microUSB cable or power it with a AC-to-DC adapter or battery to get started.
The Mega Oliymic has 4 UNO R3 interfaces, each unit has one UART, 2 I2Cs and 4 analog inputs. Two of the 4 units have the same SPI interface(Unit 1 and Unit 3), and the other two units have the same ICSP of ATmega2560 (datasheet), so the Mega Oliymic not only can expand vertically but also can extend laterally, which makes it almost compatible with all the shields designed for the Arduino UNO, Duemilanove or Diecimila and their clones.
For detail break-outs, please refer to Hardware Diagram
- 4 Arduino UNO R3 interface
- 256k Flash Memory
- 16Mhz Clock Speed
- 150mA DC Current for 3.3V Pin（500mA peak）
- microUSB connector
|Input Voltage (recommended)||6.5-12V|
|Input Voltage (limits)||6-15V|
|Digital I/O Pins||54 (of which 14 provide PWM output)|
|Analog Input Pins||16|
|DC Current per I/O Pin||40mA|
|DC Current for 3.3V Pin||150mA（500mA peak）|
|Flash Memory||256 KB of which 8 KB used by bootloader|
- Be gentle to microUSB connector.
Refer to Arduino Mega2560 Page
The Geekduino Mega Olympic can be powered via the microUSB connection or with an external power supply. The power source is selected automatically.
- microUSB. You can use your smart phone microUSB cable to power or communicate with Mega Olympic and be more environment friendly. It also has USB Overcurrent Protection which is a 500mA resettable polyfuse that protects your computer's USB ports from shorts and overcurrent.
- 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 15 volts. If supplied with less than 6.5V, however, the 5V pin may supply less than five volts and the board may be unstable. If using more than 12V, the voltage regulator may overheat and damage the board. The recommended range is 6.5 to 12 volts.
The power pins are as follows:
- VIN. The input voltage to the Mega Olympic board when it's using an external power source (as opposed to 5 volts from the microUSB 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 (6.5-12V). 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 500 mA.
- 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 Arduino Due that operate with 3.3V.
- GND. Ground pins.
Input and Output
Each of the 54 digital pins on the Mega Olympic 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 a maximum of 40 mA and has an internal pull-up resistor (disconnected by default) of 20-50 kOhms. 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 value, a rising or falling edge, or a change in value. 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 the SPI library. Mega Olympic has 2 same SPI interfaces located respectively in Unit 1 and Unit 3. The SPI pins are also broken out onto 2 ICSP headers(Unit 0 and Unit 2), which is physically compatible with the Uno, Duemilanove and Diecimila.
- 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 in the same location as the TWI pins on the UNO in each unit.
The ATMega2560 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. The 16 analog inputs are broken out onto 4 units of Mega Olympic, each unit has 4 analog inputs.
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.
Automatic (Software) Reset
Rather then requiring a physical press of the reset button before an upload, the Mega Olympic is designed in the way of Arduino Mega2560 that allows it to be reset by software running on a connected computer.
Refer to Arduino Mega2560 Page for more information.
The Mega Olympic has a number of facilities for communicating with a computer, another Arduino, or other microcontrollers. The ATmega2560 provides four hardware UARTs for TTL (5V) serial communication. An ATmega16U2 on the board channels one of these over microUSB 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 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 ATmega16U2 chip and USB connection to the computer (but not for serial communication on pins 0 and 1).
A SoftwareSerial library allows for serial communication on any of the Mega2560's digital pins.
Refer to Arduino Mega2560 Page for more information.
How to buy
Mega Olympic can be ordered through the GOF store. Its product page is located here