UART interface:easily conts to UART modules such as RS232, RS485, USB TO UART, etc.
8I/Os interface:easily conts to modules controlled by I/Os, such as 8 Push Buttons, Logic Level Converter, Mix Board, etc.
SPI interface:easily conts to SPI modules such as AT45DBXX Dataflash, L3G4200D Board, etc.
I2C interface:easily conts to I2C modules such as PCF8574 Expansion Board, PCF8563 RTC Board, LSM303DLHC Board, etc.
Character LCD interface:for conting character LCDs like LCD1602
USB contor:USB TO UART, supported by onboard converter CP2102
Potentiometer:for LCD1602 contrast adjustment
RTC battery holder
PCF8563:onboard RTC chip
768K crystal:RTC crystal
CP2102:onboard USB TO UART chip, for debugging
User LEDs jumper
User Keys jumper
For jumpers above:
short the jumper to cont to I/Os used in example code
open the jumper to cont to other custom pins via jumper wires