Source: http://www.ftdichip.com/Support/Documents/DataSheets/ICs/DS_FT232R.pdf
Source: http://electroshed.com/wordpress/usb-to-rs485-converter/
Source: http://www.tme.vn/upload/file/TMe_USB_RS485_SCH.pdf
USB TO RS485 SERIAL CONVERTER CABLE: http://www.unioncables.com/usb-to-rs485-converter-compact-pro-p00149p1.html
Module chuyển đổi của Sparkfun:
https://www.sparkfun.com/datasheets/BreakoutBoards/USB-to-RS485-Breakout-v11.pdf
File Eagle: http://www.sparkfun.com/datasheets/BreakoutBoards/USB-to-RS485-Breakout-v11.zip