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Altera_Forum
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14 years ago

Fixed Point Rounding

Hey guys, I have one more question about fixed point rounding. If you multiply two numbers and have to perform rounding, how would you do that with fixed point? I'm currently round...
Altera_Forum's avatar
Altera_Forum
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14 years ago

There are few rounding algorithms:

direct truncation (same as floor of matlab)

basic (same as nearest of matlab)

dc unbiassed (convergent of matlab)

round to nearest integer (round of matlab)

I normally go for basic: very simple:

to round 32 bits to 16 bits: add msb of truncated section (bit index 15)

to the 16 bits(b31:b16). thats all but be careful about saturation.