Free42 is a re-implementation of the HP-42S calculator and the
HP-82240 printer.  It is a complete rewrite, not using any HP code,
and it does not require an HP-42S ROM image.  Free42 is an Open Source
project. The executables and source code are released under the terms
of the GNU General Public License, version 2.  All third-party code
used in Free42 is either in the public domain, or licensed under terms
compatible with GPLv2, or used with the authors' permission.