libFTDI is an open source library to talk to FTDI chips: FT232BM, FT245BM, FT2232C, FT2232D, FT245R, FT232H and FT230X including the popular bitbang mode. The library is linked with your program in userspace, no kernel driver required. libFTDI works perfectly with Linux, Windows, MacOS X and BSD variants thanks to libusb.