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Altera_Forum
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17 years ago

Fixed-Point Problem

I have generated a sinus signal with the Megacore-NCO in Quartus. My question is: How can I convert the signed binary output to a fixed-point representation?? I want to do this, because I hav...
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Altera_Forum
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17 years ago

In fact, a signed binary number can be interpreted as a fixed point number. It depends on how many fractional bits are assumed.

If the NCO output word width is 16 bits it ranges from -32768 to 32767, considering that sine signal amplitude ranges from -1 to 1, the width of fractional part is 15 bits.

(-32768)>>15 = -1 --->Sine signal minimum value.

(32767)>>15 = 0.999969482421875 ---> Sine signal maximum value.