multiplication of two 14bits number

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i need to multiply two numbers of 14 bits and the result should have the same number of bits, how can i do this?

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What is your 14-bit number representation? Is it a fractional integer, is it signed, is it unsigned?

You would multiply the two 14-bit numbers and get a 28-bit result. You would then decide which 14-bits to keep. If you discard most-significant-bits, then for numbers that fall outside that range, you need to decide whether to saturate numbers to the most positive or negative 14-bit value. For discarded least-significant-bits, you need to determine how you want to round the number. For a discussion on that, see this thread:

http://www.alteraforum.com/forum/showthread.php?t=29931

Cheers,

Dave