I did see in the Arduino FAQ that I would not need to give out my source=20 code, but "... The LGPL does, however, require you to make available=20 object files that allow for the relinking of the firmware against=20 updated versions of the Arduino core and libraries." and "Any=20 modifications to the core and libraries must be released under the LGPL" The first looks like a (closed-source) commercial show-stopper. IE: I=20 can use it, but I'd have to make my object files openly available. The second is fine as I expect if I fix a library, I would want to give=20 that back to the community. But I'm really interested in the Chipkit and PIC32 anyway. That seems=20 to be under the same licenses, but I don't see that I need to make=20 object files available. The only restrictions I could find it that it=20 must be used on Microchip products, which is perfectly fine. Cheers, -Neil. On 5/29/2015 5:01 AM, William Westfield wrote: >> What about the license > Thorny. Much of the library and core code uses GPL or LGPL, while saying= that they don=92t intend to require that your code be open-source (which i= s contradictory, especially in embedded systems.) > > And each third party library can have additional license requirements. I= IRC, a popular SDFAT library is explicitly and intentionally viral=85 (Hmm= .. GPL3, anyway. I can=92t find =93explicitly viral=94 anywhere.) > > BillW > > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .