Specify prefix (string) for filter coefficient names



The default prefix for filter coefficient names is coeff.

For...The Prefix Is Concatenated with...
FIR filtersEach coefficient number, starting with 1. For example, the default for the first coefficient would be coeff1.
IIR filtersAn underscore (_) and an a or b coefficient name (for example, _a2, _b1, or _b2) followed by the string _sectionn, where n is the section number. For example, the default for the first numerator coefficient of the third section is coeff_b1_section3.

For example:

  -- Type Definitions
  TYPE delay_pipeline_type IS ARRAY (NATURAL range <>)
       OF signed(15 DOWNTO 0); -- sfix16_En15
  CONSTANT coeff1 : signed(15 DOWNTO 0) := to_signed(-30, 16); -- sfix16_En15
  CONSTANT coeff2 : signed(15 DOWNTO 0) := to_signed(-89, 16); -- sfix16_En15
  CONSTANT coeff3 : signed(15 DOWNTO 0) := to_signed(-81, 16); -- sfix16_En15
  CONSTANT coeff4 : signed(15 DOWNTO 0) := to_signed(120, 16); -- sfix16_En15

If you specify a string that is a VHDL reserved word, a reserved word postfix string is appended to form a valid VHDL identifier. For example, if you specify the reserved word signal, the resulting name string would be signal_rsvd. See ReservedWordPostfix for more information.

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