Printing floats with printf doesn't work on my TeensyLC - TeensyUser/doc GitHub Wiki
The code required for the printf type of functions gets very large when you use floating point numbers. If you set the optimize option to 'Smallest Code', the linker uses a reduced sets of standard libraries which do not implement printf for floats. (This is true for all Teensies, not only LC)
- Note: TeensyLC uses 'Smallest Code' as default.
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