ALPHA CP2104 is an usb-to-ttl module，used to upload program to none-usb-core-boards like ALPHA MEGA328 or ALPHA 8F328D。
CP2104 will automatically install the driver in most cases。You can also install the driver blow if the process fail.
Windows XP/Server 2003 Vista/7/8/8.1 Mac OSX
CP2104-datasheet in chinese schematic