3641 |
kaklik |
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-- increase output every fourth clock cycle |
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-- |
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library ieee; |
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use ieee.std_logic_1164.all; |
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use ieee.numeric_std.all; |
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library sychro1; |
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entity saw_generator_wrapper is |
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generic ( |
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G_INCREASE_EVERY_NTH : positive := 4 |
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); |
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port ( |
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i_clk : in std_logic; |
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i_rst : in std_logic; |
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o_valid : out std_logic; |
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o_data : out std_logic_vector |
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); |
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end saw_generator_wrapper; |
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architecture behavioral of saw_generator_wrapper is |
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signal s_modulo_counter_carry : std_logic; |
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begin |
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-- first counter that counts modulo G_INCREASE_EVERY_NTH to generate a valid signal for the second counter |
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-- and the output: |
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modulo_up_counter : entity sychro1.up_counter |
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generic map ( G_MIN_NUMBER => 0, G_MAX_NUMBER => G_INCREASE_EVERY_NTH - 1 ) |
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port map ( i_clk => i_clk, i_rst => i_rst, i_valid => '1', o_data => open, o_carry => s_modulo_counter_carry ); |
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-- the second counter: |
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main_up_counter : entity sychro1.up_counter_stdlv |
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generic map ( G_BITS => o_data'length, G_MIN_NUMBER => ( o_data'range => '0' ), G_MAX_NUMBER => ( o_data'range => '1' ) ) |
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port map( i_clk => i_clk, i_rst => i_rst, i_valid => s_modulo_counter_carry, o_data => o_data, o_carry => open ); |
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-- signal connection: |
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o_valid <= s_modulo_counter_carry; |
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end architecture; |
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