At SparkFun we use many microcontrollers compatible with Arduino and we're always looking for the simplest, most stable one. Each board is a bit different and no one board has everything we want, so we decided to make our own version that combines all our favorite features. The RedBoard combines the simplicity of the UNO's Optiboot bootloader (which is used in the Pro series), the stability of the FTDI (which we all missed after the Duemilanove was discontinued) and the R3 shield compatibility.
The RedBoard can be programmed over a USB Mini-B cable and is compatible with the Arduino IDE: Just plug in the board, select "UNO" from the board menu and you're ready to upload code. RedBoard has all of the hardware peripherals you know and love: 14 Digital I/O pins with 6 PWM pins, 6 Analog Inputs, UART, SPI and external interrupts. We've also broken out the SDA, SCL and IOREF pins that showed up on the UNO R3, so the RedBoard will be compatible with future shields.
You can power the RedBoard over USB or through the barrel jack. The on-board power regulator can handle anything from 7 to 15VDC. Check out the related items below for a compatible wall-wart power supply.
14 Digital I/O Pins (6 PWM outputs)
6 Analog Inputs
ISP Header
32k Flash Memory
16MHz Clock Speed