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Altera_Forum
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15 years ago

Are only MSBs outputted if bits are restricted?

Hi, Suppose I have a complex multiplier from the MegaWizard with inputs having 16 bits each and the outputs also having 16 bits. Because 16*16 equals 32 bits, would restricting the output to 16...
Altera_Forum's avatar
Altera_Forum
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15 years ago

When discarding most significant bits, you should use saturation logic to avoid overflow. For unsigned multiply, if any of the 6 bits on the left is set, the output should be forced to maximum value. For signed multiply, to min- or maxint, depending on the sign.