-------------------------------------------------------------------------
-- Project: JCPU, a portable 8-bit RISC CPU written in VHDL
-- This file: The ROM file for use in your VHDL design
--
-- Copyright (C) 2007 J. Ahrensfeld
--
-- 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/>.
--
-- For questions and ideas, please contact the author at jens@jayfield.org
--
--------------------------------------------------------------------------

LIBRARY ieee;
use IEEE.STD_LOGIC_1164.ALL;
USE ieee.numeric_std.ALL;


ENTITY rom IS
	Generic 
	(
		addr_width 	: integer := 2;
		data_width 	: integer := 32
	);
	Port 
	(
		addr		: in  unsigned(addr_width-1 downto 0);
		dout		: out unsigned(data_width-1 downto 0)
	);
END rom;

ARCHITECTURE itest OF rom IS 
	
	subtype word_t is unsigned(data_width-1 downto 0);
	type word_array_t is array (0 to 2**addr_width-1) of word_t;

	-- Assembled from itest.jsm
	constant word_array : word_array_t :=
	(
		X"3c011234", --	[0x00400000]	lui $1, 4660                     
		X"34225678", --	[0x00400004]	ori $2, $1, 22136
		X"3c012345", --	[0x00400008]	lui $1, 9029                     
		X"34236789", --	[0x0040000c]	ori $3, $1, 26505
		X"3c018765", --	[0x00400010]	lui $1, -30875                   
		X"34244321", --	[0x00400014]	ori $4, $1, 17185
		X"3c019876", --	[0x00400018]	lui $1, -26506                   
		X"34255432", --	[0x0040001c]	ori $5, $1, 21554
		X"3c081000", --	[0x00400020]	lui $8, 4096                     
		X"00000000", --	[0x00400024]	nop                              
		X"2c4f1234", --	[0x00400028]	sltiu $15, $2, 4660              
		X"2c4f2345", --	[0x0040002c]	sltiu $15, $2, 9029              
		X"2c4fedcc", --	[0x00400030]	sltiu $15, $2, -4660             
		X"2c4fdcbb", --	[0x00400034]	sltiu $15, $2, -9029             
		X"2c6f1234", --	[0x00400038]	sltiu $15, $3, 4660              
		X"2c6f2345", --	[0x0040003c]	sltiu $15, $3, 9029              
		X"2c6fedcc", --	[0x00400040]	sltiu $15, $3, -4660             
		X"2c6fdcbb", --	[0x00400044]	sltiu $15, $3, -9029             
		X"2c8f1234", --	[0x00400048]	sltiu $15, $4, 4660              
		X"2c8f2345", --	[0x0040004c]	sltiu $15, $4, 9029              
		X"2c8fedcc", --	[0x00400050]	sltiu $15, $4, -4660             
		X"2c8fdcbb", --	[0x00400054]	sltiu $15, $4, -9029             
		X"2caf1234", --	[0x00400058]	sltiu $15, $5, 4660              
		X"2caf2345", --	[0x0040005c]	sltiu $15, $5, 9029              
		X"2cafedcc", --	[0x00400060]	sltiu $15, $5, -4660             
		X"2cafdcbb", --	[0x00400064]	sltiu $15, $5, -9029             
		X"00000000", --	[0x00400068]	nop                              
		X"284f1234", --	[0x0040006c]	slti $15, $2, 4660               
		X"284f2345", --	[0x00400070]	slti $15, $2, 9029               
		X"284fedcc", --	[0x00400074]	slti $15, $2, -4660              
		X"284fdcbb", --	[0x00400078]	slti $15, $2, -9029              
		X"286f1234", --	[0x0040007c]	slti $15, $3, 4660               
		X"286f2345", --	[0x00400080]	slti $15, $3, 9029               
		X"286fedcc", --	[0x00400084]	slti $15, $3, -4660              
		X"286fdcbb", --	[0x00400088]	slti $15, $3, -9029              
		X"288f1234", --	[0x0040008c]	slti $15, $4, 4660               
		X"288f2345", --	[0x00400090]	slti $15, $4, 9029               
		X"288fedcc", --	[0x00400094]	slti $15, $4, -4660              
		X"288fdcbb", --	[0x00400098]	slti $15, $4, -9029              
		X"28af1234", --	[0x0040009c]	slti $15, $5, 4660               
		X"28af2345", --	[0x004000a0]	slti $15, $5, 9029               
		X"28afedcc", --	[0x004000a4]	slti $15, $5, -4660              
		X"28afdcbb", --	[0x004000a8]	slti $15, $5, -9029              
		X"00000000", --	[0x004000ac]	nop                              
		X"08104000", --	[0x004000b0]	j 0x00410000 [main]              
		X"00000000", --	[0x004000b4]	nop                              
		X"00000000", --	[0x004000b8]
		X"00000000", --	[0x004000bc]
		X"00000000", --	[0x004000c0]
		X"00000000", --	[0x004000c4]
		X"00000000", --	[0x004000c8]
		X"00000000", --	[0x004000cc]
		X"00000000", --	[0x004000d0]
		X"00000000", --	[0x004000d4]
		X"00000000", --	[0x004000d8]
		X"00000000", --	[0x004000dc]
		X"00000000", --	[0x004000e0]
		X"00000000", --	[0x004000e4]
		X"00000000", --	[0x004000e8]
		X"00000000", --	[0x004000ec]
		X"00000000", --	[0x004000f0]
		X"00000000", --	[0x004000f4]
		X"00000000", --	[0x004000f8]
		X"00000000"  --	[0x004000fc]
	);

begin

PROM_READ:
	dout <= word_array(to_integer(addr));

end itest;