UNO R3 development board UNO ATMEGA16U2 + MEGA328P with USB cable
UNO R3 is an easy-to-use open source controller introduced in 2012, the hardware compared with UNO did not change significantly, the big difference is that the USB re-serial circuit part, the use of an ATMega16U2 microcontroller, the cost has also increased, the software part as before, no major change.
1. Pin changes: Two I2C pins (SDA and SCL, just copy of Analog 4 and 5, not additional I2C interface) are added to the AREF pins, and two pins are added next to the RESET One is IOREF, which allows the expansion board to adapt to the on-board voltage, and this pin simply tells the expansion board what the current on-board voltage is (for example, UNO is 5V, can be seen as the copy of the power pin, and does not provide a level pull-up), The other is the place-up pins to be used later.
2. MORE STABLE RESET CIRCUIT. THE RESET KEY POSITION HAS ALSO CHANGED AND HAS BEEN MOVED TO THE CORNER OF THE BOARD NEAR THE USB INTERFACE FOR EASIER PRESSING.
3. The ATmega16U2 replaces 8U2, which does not mean that the R3 with 16K flash will make your code run faster, this update is a USB interface chip service, which in theory allows UNO to simulate USB HID, such as MIDI/Joystick/Keyboard.
Description Open original design circuit diagram, the development of software interface free download, but also according to the needs of their own modifications, download program is simple and convenient. A variety of interesting works can be made simply using sensors and a wide variety of electronic components (e.g. LED lights, buzzers, buttons, photoresistors, etc.).
With the high-speed microprocessing controller (ATMEGA328), the development interface and environment are simple and easy to understand, making it ideal for beginners.
description Digital I/O Digital Input/Output totals 0 to 13.
Analog I/O analog inputs/outputs total 0 to 5.
ISP download is supported.
Input voltage: no external power supply is required when connecting to the computer USB, external power supply 5V to 9V DC voltage input.
Output voltage: 5V DC voltage output and 3.3V DC voltage output.
Atmel Atmega328 microprocessing controller is used.
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