head	1.2;
access;
symbols
	bg2_23:1.2
	bg2_22:1.2
	bg2_21:1.2
	bg2_20:1.2
	bg2_16:1.2
	bg2_15:1.2
	bg2_12:1.2
	bg2_07:1.2
	isorc2008_submission:1.1
	handbook_alpha_edition:1.1
	jtres2007_submission:1.1
	bg1_07:1.1
	bg1_06:1.1
	bg1_05:1.1
	TAL_101:1.1
	TAL_100:1.1
	jtres_submission:1.1
	wises06_submission:1.1
	lctes2006_submission:1.1
	rtgc_isorc2006:1.1.0.4
	isorc2006:1.1.0.2
	rtgc_paper:1.1;
locks; strict;
comment	@# @;


1.2
date	2008.02.23.23.18.46;	author martin;	state Exp;
branches;
next	1.1;
commitid	b7347c0a9b84567;

1.1
date	2005.11.30.17.31.09;	author martin;	state Exp;
branches;
next	;
commitid	2bbc438de1d14567;


desc
@@


1.2
log
@JOP goes GPL
@
text
@--
--
--  This file is a part of JOP, the Java Optimized Processor
--
--  Copyright (C) 2001-2008, Martin Schoeberl (martin@@jopdesign.com)
--
--  This program is free software: you can redistribute it and/or modify
--  it under the terms of the GNU General Public License as published by
--  the Free Software Foundation, either version 3 of the License, or
--  (at your option) any later version.
--
--  This program is distributed in the hope that it will be useful,
--  but WITHOUT ANY WARRANTY; without even the implied warranty of
--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
--  GNU General Public License for more details.
--
--  You should have received a copy of the GNU General Public License
--  along with this program.  If not, see <http://www.gnu.org/licenses/>.
--


--
--	sc_test_slave.vhd
--
--	A simple test slave for the SimpCon interface
--	
--	Author: Martin Schoeberl	martin@@jopdesign.com
--
--
--	resources on Cyclone
--
--		xx LCs, max xx MHz
--
--
--	2005-11-29	first version
--
--	todo:
--
--


library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;

entity sc_test_slave is
generic (addr_bits : integer);

port (
	clk		: in std_logic;
	reset	: in std_logic;

-- SimpCon interface

	address		: in std_logic_vector(addr_bits-1 downto 0);
	wr_data		: in std_logic_vector(31 downto 0);
	rd, wr		: in std_logic;
	rd_data		: out std_logic_vector(31 downto 0);
	rdy_cnt		: out unsigned(1 downto 0)

);
end sc_test_slave;

architecture rtl of sc_test_slave is

	signal xyz			: std_logic_vector(31 downto 0);
	signal cnt			: unsigned(31 downto 0);

begin

	rdy_cnt <= "00";	-- no wait states

--
--	The registered MUX is all we need for a SimpCon read.
--	The read data is stored in registered rd_data.
--
process(clk, reset)
begin

	if (reset='1') then
		rd_data <= (others => '0');
	elsif rising_edge(clk) then

		if rd='1' then
			-- that's our very simple address decoder
			if address(0)='0' then
				rd_data <= std_logic_vector(cnt);
			else
				rd_data <= xyz;
			end if;
		end if;
	end if;

end process;


--
--	SimpCon write is very simple
--
process(clk, reset)

begin

	if (reset='1') then
		xyz <= (others => '0');
		cnt <= (others => '0');

	elsif rising_edge(clk) then

		if wr='1' then
			xyz <= wr_data;
		end if;

		cnt <= cnt+1;

	end if;

end process;


end rtl;
@


1.1
log
@SimpCon IO test
@
text
@d2 21
@