Just do

    autoconf (optional)
    autoheader (optional)
    ./configure --help

and choose your settings.
Optionally add special search paths for libraries and includes:
    CFLAGS="-I/path/to/includes"
    LDFLAGS="-L/path/to/libs"
Read in the manual of your shell how to set environment variables.

Then run
    ./configure <your settings>
If you are using CygWin, you might want to run it like
    ./configure --with-device=COM1
On other systems like *BSD you might consider to use equivalent options.

Then finally built it:
    make
    make install

For the parameters to run the program:
    scmxx --help
 or
    man scmxx

