Spiral Finite/Infinite Impulse Response FIlter Generator
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This tool requires the Spiral Multiplier Block generator, available at
http://spiral.ece.cmu.edu/mcm/gen.html The variable "$acm_path" in
acm2values.pl must be set to the path of its "acm" executable.


Description:

This tool generates a Transposed Direct Form implementation of a
Finite Impulse Response (FIR) filter, or an Infinite Impulse Response
(IIR) filter, from a standard difference equation. The multiplier
blocks within the design are generated from the Spiral Multiplier
Block Generator. An FIR can be generated by simply setting a_0 to one
and all other a_k constants to zero. The values of the b_k constants
form the notches of the FIR. In the Transposed Direct Form I
implementation, the IIR is generated from two separate FIR filters,
connected by an adder. In the Transposed Direct Form II
implementation, the FIR filter tool is not used at all, and the two
multiplier block outputs are taken directly through adders and input
into the flip flop array.

More information at:
http://www.spiral.net/hardware/filter.html