Implement a filter in C

Started by narcispr March 10, 2004

I'm working with a c5409 TI DSP and with code composer 2.0. I have
implemented a tone control filter with C.
When I filter a 480Hz sin the amplitude reacts as I wish but the
frequency down to 425Hz! If I increment the number of operations the
frequency down more and vice versa. If I use integers the frequency
down more than if I use floats.
How can I optimize this filter? Ther are any type of data especified
for realize fast operation (+, - and *) ?

Thank you!!!

PD: I don't Know anything of asembler ;)