License Statement Update - 4th of June 2018 Dear SwissMicros customers,

Thank you for your support in regards to the DM42 model’s GPL compliance. We have been actively working to split our firmware into “System” and “Program”. It took us long due to the complexity of the code and many third-party HALs (Hardware Abstraction Layers). We have also analyzed, reviewed and conferred third-party licenses and their respective compatibility with GPL.

We’ve separated the “Program” portion of the source code into “Free42_core” and “Free42_frontend”, both of which will be released. It took us longer than expected but we want to emphasize that we are committed to full GPL compliance.

Thank you for your patience.

SwissMicros Team
License Statement Update - 22th of April 2018 Dear SwissMicros customers,

Thank you for your support as we go through the source code compliance activities. On April 6 2018, we released a statement saying that we will ensure our users can compile modified Free42 source code into a custom DM42 firmware version. We have been occupied with analyzing a vast labyrinth of DM42 source code with multiple licensing terms which are difficult to coagulate. We underestimated the time required to anatomize the source code — i.e, to satisfy compliance from all parties and ensure accurate, truthful and fair licensing terms.

We appreciate your patience and you can expect an update from us within 3-4 weeks due to upcoming travel schedule. Michael Steinmann will be on a business trip from April 25 to May 2nd followed by a vacation until May 14 during which time we will not be shipping orders.

SwissMicros Team
License Statement - 6th of April 2018 Dear SwissMicros customers,

Thank you for your support in making DM42 come to fruition. We began development of the DM42 in 2015 followed by beta testing May 2017. We have been very fortunate to have a supportive community providing us with constructive feedback, bug reports and usability concerns throughout the development phase. We poured our heart and soul in pursuing for the best handheld RPN calculator in the world. Our goal is simple - we want to build useful tools for you with uncompromising quality, reliability, durability and robustness you expect from professional products.

Our relationship with the community is important to us; we listen to all forms of feedback and we take what our community thinks very seriously. In the past few days, there has been an escalation in a few online forums regarding the SwissMicros firmware in the DM42 calculator and GPL License requirements for code release to customers. In no way did we ever intend to violate the GPL, nor do we wish to neglect the work done by others. We sincerely recognize the work of Thomas Okken and the calculator community - Free42 is the operational jewel, the central core of DM42. We decided to use Free42 as it has been thoroughly tested over many years.

We have heard you and we are making things right.

DM42's source code comprises of several components - Free42 core, a custom DM42 shell developed by SwissMicros, FreeRTOS as a real-time operating system and several components from ST Microelectronics. Each part has a different licensing model. We are currently working hard to understand and correctly determine the proper hierarchy of licenses.

In the next few days, we will be releasing the full source code to be able to build your own DM42 firmware. All components of DM42 will be open-sourced. We think that this is the right thing to do and hopefully with the help from community, we can accelerate the development of DM42's software on Github.

Full source code will be available at:

We ask for your patience as we prepare the source code for a public release.

Thank you,
Michael Steinmann