[En-Nut-Discussion] Problems using global variables and/or floating point numbers on Nut/Os (using ethernut 5)

[Harald Kipp]

Hi Vegard,

On 19.05.2012 10:27, Vegard Aaker wrote:
 
> I am using Ethernut 5 board and nut/os version 4.10.
> 
> Do anyone have another os config file for the ethernut 5 board which
> utilize the floating point unit on the processor? Even better would be if
> anyone has both a code example and a config file I could try :)

There is no FPU on the SAM9XE, all floating point operations are done in software by the C library, newlib in your case. Using floats on embedded systems is not a good idea unless you have an FPU attached.  I'm rarely using them, but I'll try your test case. In the meantime this page will provide additional information:

http://www.ethernut.de/en/documents/ntn-4_floats.html

Regards,

Harald