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Line 1... |
-------------------------------------------------------------------------------
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-------------------------------------------------------------------------------
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--
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--
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-- The Clock Control unit.
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-- The Clock Control unit.
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-- Clock States and Machine Cycles are generated here.
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-- Clock States and Machine Cycles are generated here.
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--
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--
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-- $Id: clock_ctrl.vhd,v 1.11 2006-06-20 00:46:38 arniml Exp $
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-- $Id: clock_ctrl.vhd,v 1.12 2006-07-14 01:04:35 arniml Exp $
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--
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--
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-- Copyright (c) 2004, 2005, Arnim Laeuger (arniml@opencores.org)
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-- Copyright (c) 2004, 2005, 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 228... |
Line 228... |
if xtal3_s then
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if xtal3_s then
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psen_q <= false;
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psen_q <= false;
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end if;
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end if;
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when MSTATE2 =>
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when MSTATE2 =>
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if xtal2_s then
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-- PROG is removed at the end of XTAL2 of second machine cycle
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-- according to the user manual, PROG should be removed at the
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-- end of XTAL3 but this would raise the need to change P2 at
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-- XTAL1 or XTAL2 -> introduction of inter-xtal timing in
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-- the rest of the core.
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prog_q <= false;
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end if;
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if xtal3_s then
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if xtal3_s then
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-- RD, WR are removed at the end of XTAL3 of second machine cycle
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-- RD, WR are removed at the end of XTAL3 of second machine cycle
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rd_q <= false;
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rd_q <= false;
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wr_q <= false;
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wr_q <= false;
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-- so is PROG
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prog_q <= false;
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end if;
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end if;
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when MSTATE3 =>
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when MSTATE3 =>
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-- ALE is set at the end of XTAL3 of every machine cycle
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-- ALE is set at the end of XTAL3 of every machine cycle
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if xtal3_s then
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if xtal3_s then
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| Line 405... |
Line 399... |
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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 1.11 2006/06/20 00:46:38 arniml
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-- new input xtal_en_i gates xtal_i base clock
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--
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-- Revision 1.10 2005/11/01 21:24:21 arniml
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-- Revision 1.10 2005/11/01 21:24:21 arniml
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-- * shift assertion of ALE and PROG to xtal3
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-- * shift assertion of ALE and PROG to xtal3
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-- * correct change of revision 1.8
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-- * correct change of revision 1.8
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--
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--
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-- Revision 1.9 2005/06/11 10:08:43 arniml
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-- Revision 1.9 2005/06/11 10:08:43 arniml
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