Moreover, to the download of it is possible to add also the following packages; plugin ssp (a.k.a. Simple Serial Programmer), Development boards that adds RS232 to TTL converter board (contains two MAX232 ICs to convert voltage levels of all TIA RS-232 signals from RS-232 to 5V CMOS logic) and FT232BM development board. Chip FT232BM (from FTDI) is quite popular USB to UART bridge. Such a board like this provides an easy way to develop an electronic design with FT232BM in your breadboard, etc. In other words, you can quite simply develop an USB application. See this site for more details!