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Sushmita's avatar
Sushmita
Icon for Occasional Contributor rankOccasional Contributor
5 years ago

Latency in multiplier IP

Hi, I am using LPM mult IP for 9x9 multiplication on cyclone V GT device. I had set the latency as 3. So each DSP used to provide me 3 9x9 multipliers. So totally there would be 315 DSPs(3 * 315 -...
SengKok_L_Intel's avatar
SengKok_L_Intel
Icon for Regular Contributor rankRegular Contributor
5 years ago

Hi,


Each of the DSP block is able to fit 3 independent 9x9 multiplier. The DSP merging will automatically kicks in when there are not enough DSPs in the region of interest. The output latency setting is not supposed to impact this. From my side, no matter it is 1 or 3 clock cycles, from the Fitter -> DSP Block Usage Summary Report, it show independent 9x9 multiplier. I believe this could be something else caused the fitter error since there are many DSP configuration based on the attached file. You may starting to debug it by simplify the design with only independent 9x9 multiplier.


Regards -SK