In the ffuart.tar.gz it has one file.
The serial.c is the source codes of the FFUART as a console port, it should be put into the directory: /usr/src/linux/drivers/char/, and be compiled into the kernel.
This is a serial mouse driver, which is compliant with Plug and Play, supports dynamic detection (via serenum) and removal (either hotplug or via the device manager). The code serves as a sample for any serial-enumerable device. The behavior of the various routines is documented in the source code files.