vunit issue_vunit (issue(psl)) {
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-- VHDL declaration seem to be working
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signal a_delayed : std_logic := '0';
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signal prev_valid : boolean := false;
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-- Other VHDL code not
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-- results in parser errors
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-- during synthesis
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-- EDIT: works since fix of ghdl issue #1366
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process is
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begin
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wait until rising_edge(clk);
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a_delayed <= a;
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prev_valid <= true;
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end process;
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-- All is sensitive to rising edge of clk
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default clock is rising_edge(clk);
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-- This assertion holds
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CHECK_0_a : assert always (a -> b);
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-- You can't do anything with the declared signal
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-- Can be synthesized with GHDL, however
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-- results in error in ghdl-yosys-plugin:
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-- ERROR: Assert `n.id != 0' failed in src/ghdl.cc:172
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-- EDIT: works since fix of ghdl issue #1366
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CHECK_1_a : assert always prev_valid -> a_delayed = prev(a);
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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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entity sequencer is
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generic (
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seq : string
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);
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port (
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clk : in std_logic;
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data : out std_logic
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);
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end entity sequencer;
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architecture rtl of sequencer is
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signal index : natural := seq'low;
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function to_bit (a : in character) return std_logic is
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variable ret : std_logic;
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begin
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case a is
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when '0' | '_' => ret := '0';
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when '1' | '-' => ret := '1';
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when others => ret := 'X';
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end case;
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return ret;
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end function to_bit;
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begin
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process (clk) is
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begin
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if rising_edge(clk) then
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if (index < seq'high) then
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index <= index + 1;
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end if;
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end if;
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end process;
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data <= to_bit(seq(index));
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end architecture rtl;
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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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entity issue is
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port (
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clk : in std_logic
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);
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end entity issue;
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architecture psl of issue is
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component sequencer is
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generic (
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seq : string
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);
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port (
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clk : in std_logic;
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data : out std_logic
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);
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end component sequencer;
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signal a, b : std_logic;
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begin
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-- 0123456789
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SEQ_A : sequencer generic map ("__-__-____") port map (clk, a);
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SEQ_B : sequencer generic map ("__-__-____") port map (clk, b);
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end architecture psl;
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