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MC6809 CPU emulator written in Python

Project description

MC6809 CPU emulator written in Python

MC6809 is a Open source (GPL v3 or later) emulator for the legendary 6809 CPU, used old homecomputer Dragon 32/64 and Tandy TRS-80 Color Computer (CoCo) built in the 1980s…

Tested with Python 3.6, 3.7, 3.8 and PyPy3

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A example usage can be find in: MC6809/


~$ python3 -m venv MC6809
~$ cd MC6809
~/MC6809 $ source bin/activate
(MC6809) ~/MC6809 $ pip3 install MC6809
(MC6809) ~/MC6809$ MC6809 --help

  MC6809 is a Open source (GPL v3 or later) emulator for the legendary 6809
  CPU, used in 30 years old homecomputer Dragon 32 and Tandy TRS-80 Color
  Computer (CoCo)...

  Created by Jens Diemer


  --version  Show the version and exit.
  --help     Show this message and exit.

  benchmark  Run a 6809 Emulation benchmark

There is a simple benchmark. Run e.g.:

(MC6809) ~/MC6809$ MC6809 benchmark --help


~$ cd MC6809-clone
~/MC6809-clone $ make pytest
~/MC6809-clone $ poetry run pytest


To profile, e.g.: $ cd MC6809-clone /MC6809-clone $ make profile or /MC6809-clone $ poetry run MC6809 profile }}}


  1. Update ‘’
  2. Use bottle for http control server part

unimplemented OPs:

  • SWI / SWI2 / SWI3
  • SYNC


(Some of the points are related to DragonPy Emulator)

  • 10.02.2020 - v0.6.0

    • modernize project and sources
    • skip support for Python 2
    • minimal Python v3.6
  • 19.10.2015 - v0.5.0

    • Split CPU with mixin inheritance

    • Optimizing:

      • remove .get() function calls from registers
      • move Condition Code Register (CC) into CPU via mixin class
    • Bugfix TFR and EXG by convert_differend_width()

    • Run DragonPy unittests on travis CI, too.

  • 24.08.2015 - v0.4.6

    • Add a “max_delay”, to fix the “freeze” after a speed limit change
    • rename some of the “speed limit” variables
  • 21.08.2015 - v0.4.5

    • deactivate ‘’ - TODO: update it!
    • update cli unittests
    • update README and code cleanup
  • 10.08.2015 - v0.4.4 - bugfix and cleanup the tests

  • 10.08.2015 - v0.4.3 - run unittests with nose

  • 27.05.2015 - v0.4.2 - Add MC6809/

  • 26.05.2015 - v0.4.0, 0.4.1 - Split MC6809 from DragonPy

  • 22.09.2014 - Remove hacked CPU skeleton generator scripts with commit ac903a8f

  • 14.09.2014 - Release v0.2.0 - Add a speedlimit, config dialog and IRQ: Forum post 11780

  • 05.09.2014 - Release v0.1.0 - Implement pause/resume, hard-/soft-reset 6809 in GUI and improve a little the GUI/Editor stuff: v0.1.0 see also: Forum post 11719.

  • 27.08.2014 - Run CoCo with Extended Color Basic v1.1, bugfix transfer BASIC Listing with 8fe24e5…697d39e see: Forum post 11696.

  • 20.08.2014 - rudimenary BASIC IDE works with 7e0f16630…ce12148, see also: Forum post 11645.

  • 05.08.2014 - Start to support CoCo, too with 0df724b, see also: Forum post 11573.

  • 04.08.2014 - Use the origin Pixel-Font with Tkinter GUI, see: Forum post 4909 and Forum post 11570.

  • 27.07.2014 - Copyrigth info from Dragon 64 ROM is alive with 543275b, see: Forum post 11524.

  • 29.06.2014 - First “HELLO WORLD” works, see: Forum post 11283.

  • 27.10.2013 - “sbc09” ROM works wuite well almist, see: Forum post 9752.

  • 16.10.2013 - See copyright info from “Simple6809” ROM with 25a97b6 see also: Forum post 9654.

  • 10.09.2013 - Start to implement the 6809 CPU with 591d2ed

  • 28.08.2013 - Fork “Apple ][ Emulator” written in Python: to


Note: this file is generated from README.creole 2020-02-10 21:04:15 with "python-creole"

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