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Registered: ‎04-08-2009

Design a narrow band using FIR_Compiler 4.0

Dear all,


I want to design a narrow band low pass filter which is more than 2400 taps

but, my device target is Spartan-3A DSP 1800A which has 84 DSP48As only

i try to use Interpolated FIR  architecture and Systolic Multi-MAC to implement it

The frame of Systolic Multi-MAC is base on figure 5 of datasheet of FIR_Compiler 4.0 (DS534)


Now,  i want to implement Systolic Multi-MAC using FIR_Compiler 4.0



if a filter has 1024 taps and 16 DSP48As will be used

so, there are 64 coefficients map to one DSP48A

(c1~c64 as a coefficeint set, c65~c128 as a coefficient set, and so on)


but, i set a value into the field (Number of coefficient sets) which is larger than 1

then the IP create an input port which named filter_sel

this port is used to selecte one coefficient set to calculate only

According to the frame of Systolic Multi-MAC, this port should not exist.


please help me to make sure the use of the port


thanks a lot

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Registered: ‎08-14-2007

Re: Design a narrow band using FIR_Compiler 4.0

The FILTER_SEL port identifies which set of coefficients will be used to process the current set of data. If there's no this port, how do u determine which coef set you wanna use? Plus, changing coef sets number won't always affect DSP Slice usage. U can track this by viewing Resource Estimates tab.

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