problem in cos funtion

Question

sir/mam,

i have used ieee math_real ,now

k1 : bwlmulti port map (a1,f,q1);

qout <= cos (q1);

here shows an error that "cos can't have such operand in this context". plz help me out of problem.:cry:

altera_forum · Answer

You cannot use the math_real package for synthesis. In addition, you cannot use real types for synthesis.  They are only suitable for simulation.

altera_forum · Answer

If I need tackle cos operation, how can I do it

altera_forum · Answer

For a start, its best to use fixed point rather than floating point.

There are two main methods for cos function:

Use a lookup table.

Use the CORDIC algorithm. There are many implementations of this. Or have a look here:

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