Sine function on F28335

Tim11828

Hi all,

I tried using the sine function with F28335, and the result is not what I'm expecting. I have included the rts2800_fpu32.lib, and math.h in the project, but still not working. Any suggestions?

Thanks,

Tim

over 16 years ago

0 Yaminov Kamil over 16 years ago

Prodigy 130 points

detaGood question is a half of answer! Try to describe more detail your problem.

0 Tim11828 over 16 years ago in reply to Yaminov Kamil

Expert 1845 points

I created a simple test project with this line of code:

test = sin(45.0);

and then looked at the value of test. It is not what it should be.

Tim

0 Lori Heustess over 16 years ago in reply to Tim11828

TI__Guru* 93800 points

Tim said:

I created a simple test project with this line of code:

test = sin(45.0);

and then looked at the value of test. It is not what it should be.

The sin() function takes an argument in radians, not degrees.

On a side note, check out the 28x FPU fastRTS library for a sin function that leverages a lookup table in the ROM for performance.

Regards

Lori

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0 Tim11828 over 16 years ago in reply to Lori Heustess

Expert 1845 points

Hi Lori,

Thanks for the response. I remember now seeing this: cos(A*6.283185307), in the define for _IQsinPU.

Tim

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Sine function on F28335