Old versions of CMSIS had a weird "only for use with ARM hardware" license header, which also carried through into most BSPs. I don't think this was resolved until around CMSIS 4, so it might just be a matter of front porting since it looks like normal STM32 stuff which is mostly permissively licensed now.
Yeah. And ngl porting up to newer versions of CMSIS isn't too terribly hard. I'm looking at porting up to CMSIS 6 soon and it doesn't look like it'll be that bad either.
Presumably the source included the TTF files from which the rasterized bitmap resources were automatically generated. Including the pre-rasterized bitmaps extracted from a previous release should not be a problem as typefaces and bitmap fonts are not subject to copyright in the US, vs vector font files which are eligible for copyright as computer programs.
The Bluetooth stack, except for a stub that will function in an emulator
This seems unfortunate, and looks to be one of the most critical gaps in the source release.
The STM peripheral library
You can get this from ST no problem, although it is only licensed for use on STM devices.
The voice codec
It should be feasible enough to replace this.
ARM CMSIS
The old versions with non-free licenses are still available from ARM or ST, and the recent versions are Apache licensed (but some porting of code might be required to use to newer versions).
For the Pebble 2 HR, the heart rate monitor driver
This was probably based on sample code from the vendor which could be replaced.
I remember reading that the Bluetooth stack was one of the main differentiators for Pebble at the time due to its reliability, shame it's not included here.
In 2014, that certainly was true. Every open source Bluetooth stack (i.e., Android, Linux and FreeBSD) was buggy and unreliable. Since then they rewrote the Bluetooth stack in Android twice, and finally what's in AOSP is quite comprehensive and reliable. It's now been merged into ChromeOS as well.
I feel like it's the same about many of the items mentioned above, the free/libre offering in that space are a lot more polished than was the case 9-10 years ago. Back then the audio codec was still a patent encumbered minefield, now you can just use opus. The quality and diversity of free fonts is ordered of magnitudes above what it was 10 years ago.
In short, it should be much easier for Eric to fill those gaps with free/open offerings than it was 10 years ago.
- All of the system fonts
- The Bluetooth stack, except for a stub that will function in an emulator
- The STM peripheral library
- The voice codec
- ARM CMSIS
- For the Pebble 2 HR, the heart rate monitor driver