Working with Cosine

I would like to use the COS function to determine which part of a sine wave I am on. What I do not know is what the data is going to look like and how accurate the data will be. Thanks in advance for any and all help.

Best, Ed

i'll suggest you something else, take a few reading of your signal with the internal adc, store those data into array or internal EPROM and play with. Refering to a table will be much easier and much code efficient. BUT it's my own opinion, probably Melanie or somebody else have a better solution.

Hi,Ed

You'll get -127 to +127 as a result ... so, look at the highest digit to see where you are on your sine ( ascending = 1, descending = 0 ).

But do not forget to convert degrees as here:

Result = COS ( X * 256 / 360 ) ... for X in degrees.
Side = Result.7

Looking also to SIN highest digit will show you the quarter where you are ...

For accuracy ... 7 bits !!!

Alain