i solve the problem but i have a question
i have the following question.
I realized a distrubuited complex fir
the coefficient are defined in a package as follows:
....
type vect is array (0 to N_channels-1) of std_logic_vector(N_bit -1 downto 0);
constant h_REAL :vect :=("0000000001","1100001111","1101110101","0000111 100","0101011101","1101011100","1110100100","10101 00100");
constant h_IMAG :vect :=("1010110100","1101101111","0001110101","0011111 101","0101011101","1101011100","0000100100","00000 01100");
.....
this number are useb by the N taps and are passed as generic
entity complex_fir_tap is
generic(
constant H_REAL1 : STD_LOGIC_VECTOR (N_bit-1 downto 0);
constant H_IMAG1 : STD_LOGIC_VECTOR (N_bit-1 downto 0)
);
....
whe i synthesize and implement my design the ISE suite use DSP48 if i set the relative option to AUTO in the synthesis option.
Being the value constant why the DSP48 are used.
If i force in the synthesis options the tool to not use DSP48 it realize constant multipliers or normal multipliers
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