SainSmart UNO ATMEGA328P-PU ATMEGA8U2 Microcontroller AVR USB board for Arduino+USB cable

SainSmart UNO ATMEGA328P-PU ATMEGA8U2 Microcontroller AVR USB board for Arduino+USB cable

 

SainSmart UNO ATMEGA328P-PU ATMEGA8U2 Microcontroller AVR USB board for Arduino+USB cable

Overview: 

NB: Board color may be blue or black with the same funcionality

SainSmart UNO R3 board is our new 2013 improved version product! It's More Powerful than the original UNO R3, now it has perfect quality and much more performance , we believe it will provide exciting use experience to you!

 In addition to all the features of the previous board, the Uno R3 now uses an ATMega16U2 instead of the ATMega8U2 chip. This allows for faster transfer rates and the ability to have the Uno show up as a keyboard, mouse, joystick, etc. No drivers needed for Linux or Mac (inf file for Windows is needed),The Arduino Uno is a microcontroller board based on the ATmega328 (datasheet). It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, 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.

Note: SainSmart Uno R3 requires the Arduino drivers folder in order to install properly on some computers. We have tested and confirmed that the UNO R3 can be programmed in older versions of the IDE. However, you need to have Arduino installed on that machine when using the R3 on a new computer at the first time.

 

Revision 3 of the board has the following new features:

  • 1.0 pinout: added SDA and SCL pins that are 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 with both the board that uses the AVR, which operates with 5V and with the Sainsmart Due that operates 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.
 
 

 

Sainsmart Uno R3 2012

Sainsmart Uno R3 2013

Picture review

 

 

Microcontroller

ATmega328

MEGA328P-AU

Operating Voltage

5V

3.3V-5V (Switch)

Input Voltage (recommended)

7-12V

7-12V

Input Voltage (limits)

6-20V

6-20V

Digital I/O Pins

14 (of which 6 provide PWM output)

14 (of which 6 provide PWM output)

Analog Input Pins

6

8 (Add A6/A7 port)

DC Current per I/O Pin

40 mA

40 mA

DC Current for 3.3V Pin

50 mA

50 mA

Flash Memory

32 KB (ATmega328) of which 0.5 KB used by bootloader

32 KB (ATmega328) of which 0.5 KB used by bootloader

SRAM

2 KB (ATmega328)

2 KB (ATmega328)

EEPROM

1 KB (ATmega328)

1 KB (ATmega328)

Clock Speed

16 MHz

16 MHz

 

Package List

1X Sainsmart UNO R3 2012 MEGA328P ATMEGA16U2

1X USB Cable

1.   3.3V/5V Supply Voltage and IO Voltage can be switched at the same time.

2.    More 3.3V modules supported, such as Xbee module, Bluetooth module, RF module, GPRS module, GPS module, LCD5110 Backlight and so on, but the original version can only support 5V IO.

3.     Controller uses SMD MEGA328P-AU chip. Add A6/A7 port.

 

  •  Parameter: UNO R3
  • 5V Electric current: 500MA
  • 3.3V Electric current: 50MA
  • Input Voltage: 7-12V 

 

Description:
Digital I / O digital input / output of 0 to 13.
Analog I /O analog input / output of 0 to 7.
Support ISP downloads function.
Input voltage: no external power supply when connected to the computer USB, external power supply 5V ~ 9V DC voltage input.
Output voltage: 5V DC voltage output and 3.3V DC voltage output.

The Uno differs from all preceding boards in that it does not use the FTDI USB-to-serial driver chip. Instead, it features the Atmega8U2 programmed as a USB-to-serial converter. Revision 2 of the Uno board has a resistor pulling the 8U2 HWB line to ground, making it easier to put into DFU mode.

"Uno" means one in Italian and is named to mark the upcoming release of Arduino 1.0. The Uno and version 1.0 will be the reference versions of Arduino, moving forward. The Uno is the latest in a series of USB Arduino boards, and the reference model for the Arduino platform; for a comparison with previous versions, see the index of Arduino boards.

MicrocontrollerATmega328
Operating Voltage5V
Input Voltage (recommended)7-12V
Input Voltage (limits)6-20V
Digital I/O Pins14 (of which 6 provide PWM output)
Analog Input Pins6
DC Current per I/O Pin40 mA
DC Current for 3.3V Pin50 mA
Flash Memory32 KB (ATmega328) of which 0.5 KB used by bootloader
SRAM2 KB (ATmega328)
EEPROM1 KB (ATmega328)
Clock Speed16 MHz

Schematic & Reference Design

EAGLE files: arduino-uno-reference-design.zip

Schematic: arduino-uno-schematic.pdf

 

Summary

Microcontroller

ATmega328

Operating Voltage

5V

Input Voltage (recommended)

7-12V

Input Voltage (limits)

6-20V

Digital I/O Pins

14 (of which 6 provide PWM output)

Analog Input Pins

6

DC Current per I/O Pin

40 mA

DC Current for 3.3V Pin

50 mA

Flash Memory

32 KB (ATmega328) of which 0.5 KB used by bootloader

SRAM

2 KB (ATmega328)

EEPROM

1 KB (ATmega328)

Clock Speed

16 MHz

 

Schematic & Reference Design

EAGLE files: arduino-uno-reference-design.zip

Schematic: arduino-uno-schematic.pdf

 

Power

The Arduino Uno 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 be 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 Arduino 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. The regulated power supply used to power the microcontroller and other components on the board. This can come either from VIN via an on-board regulator, or be supplied by USB or another regulated 5V supply.
  • 3V3. A 3.3 volt supply generated by the on-board regulator. Maximum current draw is 50 mA.
  • GND. Ground pins.

 

Memory

The ATmega328 has 32 KB (with 0.5 KB used for the bootloader). It also has 2 KB of SRAM and 1 KB of EEPROM (which can be read and written with the EEPROM library).

 

Input and Output

Each of the 14 digital pins on the Uno 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). Used to receive (RX) and transmit (TX) TTL serial data. These pins are connected to the corresponding pins of the ATmega8U2 USB-to-TTL Serial chip.
  • External Interrupts: 2 and 3. 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: 3, 5, 6, 9, 10, and 11. Provide 8-bit PWM output with the analogWrite() function.
  • SPI: 10 (SS), 11 (MOSI), 12 (MISO), 13 (SCK). These pins support SPI communication using the SPI library.
  • 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.

The Uno has 6 analog inputs, labeled A0 through A5, 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 the analogReference() function. Additionally, some pins have specialized functionality:

  • TWI: A4 (SDA) and A5 (SCL). Support TWI communication using the Wire library.

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.

See also the mapping between Arduino pins and ATmega328 ports?.

 

Communication

The Arduino Uno has a number of facilities for communicating with a computer, another Arduino, or other microcontrollers. The ATmega328 provides UART TTL (5V) serial communication, which is available on digital pins 0 (RX) and 1 (TX). An ATmega8U2 on the board channels this serial communication over USB and appears as a virtual com port to software on the computer. The '8U2 firmware uses the standard USB COM drivers, and no external driver is needed. However, on Windows, a .inf file is required. The Arduino software includes a serial monitor which allows simple textual data to be sent to and from the Arduino board. The RX and TX LEDs on the board will flash when data is being transmitted via the USB-to-serial 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 Uno's digital pins.

The ATmega328 also supports I2C (TWI) and SPI communication. The Arduino software includes a Wire library to simplify use of the I2C bus; see the documentation for details. For SPI communication, use the SPI library.

 

Programming

The Arduino Uno can be programmed with the Arduino software (download). Select "Arduino Uno from the Tools > Board menu (according to the microcontroller on your board). For details, see the reference and tutorials.

The ATmega328 on the Arduino Uno comes preburned with a bootloader that allows you to upload new code to it without the use of an external hardware programmer. It communicates using the original STK500 protocol (referenceC header files).

You can also bypass the bootloader and program the microcontroller through the ICSP (In-Circuit Serial Programming) header; see these instructions for details.

The ATmega8U2 firmware source code is available . The ATmega8U2 is loaded with a DFU bootloader, which can be activated by connecting the solder jumper on the back of the board (near the map of Italy) and then resetting the 8U2. You can then use Atmel's FLIP software (Windows) or the DFU programmer (Mac OS X and Linux) to load a new firmware. Or you can use the ISP header with an external programmer (overwriting the DFU bootloader). See this user-contributed tutorial for more information.

 

Automatic (Software) Reset

Rather than requiring a physical press of the reset button before an upload, the Arduino Uno 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 theATmega8U2 is connected to the reset line of the ATmega328 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 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 Uno 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 Uno. 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 Uno 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.

 

USB Overcurrent Protection

The Arduino Uno 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.

 

Physical Characteristics

The maximum length and width of the Uno PCB are 2.7 and 2.1 inches respectively, with the USB connector and power jack extending beyond the former dimension. Four 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.

Package list:

1x SainSmart UNO

1x USB Cable

 

 

Write a review

Note: HTML is not translated!
    Bad           Good

Express Checkout

includes GST

Price includes GST
 

  • Views: 25174
  • Product Code: SainSmart UNO ATMEGA328P-PU
  • Availability: In Stock
  • AUD $26.95

Tags: SainSmart, UNO, ATMEGA328P-PU, Arduino, compatible