Hello
New to using the Spark here - I want to vary the amplitude of an LED is a sinusoidal manner through one of the analogue ports, but it seems there is no sine function to work with that I can find.
How do I generate a sine wave, say based upon the timer? Will be straightforward once I know how to find that function!
Thanks
Hi @PaulR
In C the sine function is in
#include <math.h>
So you need to include that. I believe that sin(x) in traditional C is only available for double datatype, but in more modern compilers you can use double, float, and long double.
PaulR, you can also use a sine lookup table (256 bytes in size) if you want faster control but your application may not need it. There are plenty of Arduino examples to cull code from. 
Reminds me of how I made a Mood lamp ny hand using a PIC chip… wooooo. Good old days! 
Thanks, the include dealt with that. Appreciate the suggestion of the lookup table, speed should be fine with the function.