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-- NOTE : THE PC DOES NOT GET FAT!!!
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LIBRARY IEEE;
USE IEEE.std_logic_1164.ALL;
--
LIBRARY EXEMPLAR;
USE EXEMPLAR.exemplar_1164.ALL;
USE EXEMPLAR.exemplar.ALL;
--
LIBRARY WORK;
USE WORK.synthesis_utilities.ALL;
USE WORK.synthesis_parameters.ALL;
USE WORK.global_environment.ALL;
--
ENTITY program_counter_unit IS
PORT (increment, load_page, load_offset, reset : IN std_logic);
END program_counter_unit;
--
ARCHITECTURE Concurrent OF program_counter_unit IS
BEGIN
PROCESS (reset, increment, load_page, load_offset)
BEGIN
IF reset'EVENT THEN
IF (pc_out/=NULL AND pc_out/=zero_12) THEN DEALLOCATE(pc_out); END IF;
pc_out := zero_12;
ELSIF increment'EVENT THEN
IF (pc_out=NULL OR pc_out=zero_12) THEN
pc_out := NEW twelve_node;
pc_out.val:="000000000000";
pc_out.link:=NULL;
END IF;
pc_out.val := pc_out.val + "01";
END IF;
IF load_offset'EVENT THEN
IF (pc_out=NULL OR pc_out=zero_12) THEN
pc_out := NEW twelve_node;
pc_out.val:="000000000000";
pc_out.link:=NULL;
END IF;
pc_out.val (7 DOWNTO 0) := mar_offset_out.val;
END IF;
IF load_page'EVENT THEN
IF (pc_out=NULL OR pc_out=zero_12) THEN
pc_out := NEW twelve_node;
pc_out.val:="000000000000";
pc_out.link:=NULL;
END IF;
pc_out.val (11 DOWNTO 8) := mar_page_out.val;
END IF;
test;
END PROCESS;
END Concurrent;