readme.txt

和NIOS功能一样的CPU

/***************************************************************************
    UT Nios Soft-Core Processor v1.00
    Copyright (C) by Franjo Plavec 2004

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License Version 2, as
    published by the Free Software Foundation.

    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, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    The full text of the GNU General Public License is given at the end of
    this file.
*****************************************************************************/

/******************************Usage instructions*****************************
	To use UT Nios, the Nios Embedded Processor from Altera
	has to be installed on your system, since the bus, memory
	and peripheral logic is necessary to build a useful system.

	UT Nios can be used in a system in place of Altera Nios.
	When configuring Altera Nios, make sure that cache support is
	disabled, and that the "Multiplier" option in Hardware tab of
	the Nios configuration page in SOPC Builder is set to "Software".
	This ensures that the libraries generated by the SOPC Builder
	do not use caches and hardware multiplication, which are not
	currently supported by UT Nios.

	UT Nios has several customizable parameters, of which at least two
	have to be customized for the processor to function properly.
	The two options are START_ADDRESS and VECTOR_TABLE_ADDRESS.
	  START_ADDRESS defines the starting address of the program.
	The value of this parameter should be equal to the "Address" of
	the "Reset Location" in "More Settings" tab of the SOPC Builder
	  VECTOR_TABLE_ADDRESS - memory address of the interrupt vector table.
	The value of this parameter should be equal to the "Address" of the
	"Vector Table" in "More Settings" tab of the SOPC Builder.
	See the nios_0.v file for more details.
	
	To use UT Nios instead of Altera Nios, simply replace the nios_0.v
	file in the project folder generated by the SOPC Builder with the nios_0.v
	file provided (Notice that "nios_0" is a default name for the first
	processor in the system. If you change the processor name manually,
	the file name will correspond to the name given to the processor.
	In such case, the file nios_0.v should be renamed to the given name,
	and the top level module in the file should also be given the same name.)
	If the instruction decoder is implemented in memory (default), two
	mif (Memory Initialization File) files (instr_mem_one.mif and
	instr_mem_two.mif) should be copied to the project folder.

	To simulate the system behaviour using ModelSim, the files instr_mem_one.dat
	and instr_mem_two.dat have to be copied to the simulation folder (along
	with all of the changes described above).
	The simulation folder is usually named <system name>_sim, where the
	<system name> is the name of the Nios based system, as specified on the
	page 2a of the MegaWizard Plug-In Manager when instantiating the system.

	Files instr_mem_one.hex and instr_mem_two.hex are not used in 
	a Quartus based design flow, and are provided for compatibility
	with other tools.

	
	This file comes AS IS, WITHOUT ANY GUARANTEED SUPPORT!
	For more information on UT Nios, refer to the master's thesis:
	F. Plavec: Soft-Core Processor Design, which can be downloaded from:
	http://www.eecg.toronto.edu/~plavec/utnios.html

	Comments and bug reports are welcome, and should be sent to:
	[e-mail], with subject line "UT Nios Comment/Bug Report"

	Bug report should ideally be accompanied with the Quartus project which
	exhibits the problem, along with the source code of the program running
	on the system, and a detailed description of the problem.
	Before filing a bug report, please make sure that the cause of the
	problem is UT Nios. The easiest way to verify this is to use the
	Altera Nios in the same	system configuration, and make sure that the
	problem	disappears. If the problem remains, the problem is likely in
	the bus or peripheral logic.
*****************************************************************************/

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