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Altera_Forum
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14 years ago

FIR Megafunction Signed (Fractional) Binary only?

I am using Quartus II 11.0. It looks like the FIR filter Megafunction supports only Signed Binary or Signed Fractional Binary. As far as I understand, this means that the MSB is the sign bit, a...
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Altera_Forum
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14 years ago

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Why isn't there a twos-complement option?

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Both are 2's compliment. Signed fractional binary format results in the same hardware implementation as signed binary format, the binary point is conceptual only.

Its quite possible the GUI displays things differently, or the coefficients can be passed in as fractional integers represented as what appear to be floating point values in a text file, but ultimately the hardware will look the same.

Cheers,

Dave