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+# Py65
+
+The Py65 project provides software building blocks for simulating hardware
+systems based on the 6502 microprocessor and its derivatives.  It has the 
+following goals:
+
+ - Focus on ease of use and modularity rather than performance.  Py65 is
+   written in the Python programming language for productivity, while
+   similar programs are written in C for performance.
+
+ - Enable simulations to be created for systems where it might have 
+   otherwise not been practical, such as homebuilt computers. 
+
+ - Rigorously unit test all of the components.  While the tools provided
+   by Py65 may not always be perfect, their behavior is verified through 
+   tests so unexpected results are minimized.
+   
+## Installation
+                          
+Py65 packages are [available](http://pypi.python.org/pypi/py65) on the 
+Python Package Index (PyPI).  You download them from there or you can 
+use `easy_install` to automatically install or upgrade Py65:
+
+    $ easy_install -U py65
+
+Alternatively, you can [download](http://github.com/mnaberez/py65/downloads) 
+a package from GitHub in `.tar.gz` or `.zip` format.  After extracting the 
+package, use the following command to install Py65:
+
+    $ python setup.py install
+
+## Devices
+
+The following devices are simulated at this time:
+
+ - `mpu6502` simulates the orignal NMOS 6502 microprocessor from MOS
+    Technology, later known as Commodore Semiconductor Group (CSG). At this
+    time, all of the documented opcodes are supported.  Support for the
+    illegal opcodes is planned for the future.
+
+ - `mpu65c02` simulates a generic CMOS 65C02 microprocessor. There were
+    several 65C02 versions from various manufacturers, some with more opcodes
+    than others. This simulation is based on the W65C02S from the Western
+    Design Center (WDC).
+
+## Monitor
+
+Py65 includes a console-based machine language monitor (sometimes also called
+a debugger).  This program, `py65mon`, allows you to interact with the
+simulations that you build.  Its features include:
+
+ - Commands that are largely compatible with those used in the monitor of
+   the popular VICE emulator for Commodore computers.
+
+ - Ability to load, dump, and fill memory.
+
+ - Simple assemble and disassemble capability, including support for labels 
+   and labels with offsets.
+
+## Documentation
+
+Py65 documentation is written using [Sphinx](http://sphinx.pocoo.org/) and is
+periodically published to 
+[http://6502.org/projects/py65/](http://6502.org/projects/py65/).
+
+## Contributors
+
+These people are responsible for Py65:
+
+ - [Mike Naberezny](http://github.com/mnaberez) is the original author of 
+   Py65 and is the primary maintainer.
+ 
+ - [Oscar Lindberg](http://github.com/offe) started the 65C02 simulation 
+   module and contributed greatly to its implementation.