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Line 1... |
-------------------------------------------------------------------------------
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-------------------------------------------------------------------------------
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--
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--
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-- The Decoder unit.
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-- The Decoder unit.
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-- It decodes the instruction opcodes and executes them.
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-- It decodes the instruction opcodes and executes them.
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--
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--
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-- $Id: decoder.vhd,v 1.19 2005-06-11 10:08:43 arniml Exp $
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-- $Id: decoder.vhd,v 1.20 2005-09-13 21:08:34 arniml Exp $
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--
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--
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-- Copyright (c) 2004, Arnim Laeuger (arniml@opencores.org)
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-- Copyright (c) 2004, Arnim Laeuger (arniml@opencores.org)
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--
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--
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-- All rights reserved
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-- All rights reserved
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--
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--
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| Line 321... |
Line 321... |
need_address_v := not clk_second_cycle_i or
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need_address_v := not clk_second_cycle_i or
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(clk_second_cycle_i and assert_psen_s);
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(clk_second_cycle_i and assert_psen_s);
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case clk_mstate_i is
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case clk_mstate_i is
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when MSTATE1 =>
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when MSTATE1 =>
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if need_address_v and not int_pending_s then
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if need_address_v then
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if ea_i = '0' then
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if ea_i = '0' then
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if not int_pending_s then
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pm_read_pmem_o <= true;
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pm_read_pmem_o <= true;
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end if;
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else
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else
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bus_read_bus_s <= true;
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bus_read_bus_s <= true;
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p2_output_pch_o <= true;
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p2_output_pch_o <= true;
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end if;
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end if;
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end if;
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end if;
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if not clk_second_cycle_i then
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if not clk_second_cycle_i then
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if not int_pending_s then
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if not int_pending_s then
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opc_read_bus_s <= true;
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opc_read_bus_s <= true;
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| Line 1950... |
Line 1954... |
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-------------------------------------------------------------------------------
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-------------------------------------------------------------------------------
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-- File History:
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-- File History:
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--
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--
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-- $Log: not supported by cvs2svn $
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-- $Log: not supported by cvs2svn $
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-- Revision 1.19 2005/06/11 10:08:43 arniml
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-- introduce prefix 't48_' for all packages, entities and configurations
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--
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-- Revision 1.18 2005/06/09 22:18:28 arniml
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-- Revision 1.18 2005/06/09 22:18:28 arniml
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-- Move latching of BUS to MSTATE2
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-- Move latching of BUS to MSTATE2
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-- -> sample BUS at the end of RD'
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-- -> sample BUS at the end of RD'
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--
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--
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-- Revision 1.17 2005/05/09 22:26:08 arniml
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-- Revision 1.17 2005/05/09 22:26:08 arniml
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