DragonPyEmulator 0.2.0

Current state

The Dragon 32 / 64 and CoCo ROMs works in Text mode. Also the “single board computer” ROMs sbc09, Simple6809 and Multicomp6809 works well.

There is a rudimentary BASIC editor with save/load BASIC programm listings direct into RAM.

Looks like this:

(older version of the editor)

...path/to/DragonPy$ python2 DragonPy_CLI.py --verbosity 5 --machine=Vectrex run --trace --max_ops 1

BASIC Editor

Use “BASIC editor / open” in the main menu to open the editor.

You can load/save ASCII .bas files from you local drive or just type a BASIC listing ;) With “inject into DragonPy” you send the current listing from the Editor to the Emulator and with “load from DragonPy” back from emulator to editor. Note: The is currently no “warning” that un-saved content will be “overwritten” and there is no “auto-backup” ;)

The “renumbering” tool can be found in the editor window under “tools”

You can also run the BASIC Editor without the Emulator:

...path/to/DragonPy$ python2 DragonPy_CLI.py editor

A rudimentary BASIC source code highlighting is available and looks like this:

Special feature: The Line number that are used in GOTO, SOGUB etc. are extra marked on the left side.

Currently the code are only differate into:

• DATA

• Strings

• Comments

• Code

TODO: parse the code, to coloring it differently.

ROMs

The Dragon ROMs can be downloaded here:

• http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/

There is a simple shell script to automatic download and extract the Dragon ROMs:

...path/to/DragonPy$ ./download_ROMs.sh

Quick start:

# clone the repro:
~$ git clone https://github.com/jedie/DragonPy.git

# Alternative download as .zip: https://github.com/jedie/DragonPy/archive/master.zip

~$ cd DragonPy

# Download all ROM files:
~/DragonPy$ ./download_ROMs.sh

# Start Dragon 32
~/DragonPy$ python2 DragonPy_CLI.py --machine=Dragon32 run

run unittests

You can run tests with PyPy, Python 2 and Python 3:

...path/to/DragonPy$ python -m unittest discover

All variants:

...path/to/DragonPy$ python2 -m unittest discover
...path/to/DragonPy$ python3 -m unittest discover
...path/to/DragonPy$ pypy -m unittest discover

create coverage report

install coverage for python 2:

~$ sudo pip2 install coverage

...path/to/DragonPy$ coverage2 run --source=dragonpy setup.py test
...path/to/DragonPy$ coverage2 coverage2 html
# e.g.:
...path/to/DragonPy$ firefox htmlcov/index.html

Dragon Keyboard

The keyboard mapping is stored into dragonpy/Dragon32/keyboard_map.py.

Some notes:

• “CLEAR” is mapped to “Home” / “Pos 1” key

• “BREAK” is mapped to “Escape” button

• “LEFT” is mapped to left cursor key and to normal backspace, too.

A “auto shift” mode is implemented. So normal lowercase letters would be automaticly converted to uppercase letters.

10 CLS
20 FOR I = 0 TO 255:
30 POKE 1024+(I*2),I
40 NEXT I
50 I$ = INKEY$:IF I$="" THEN 50

DragonPy schematic

The main thread with GUI starts the sub thread with CPU+Memory+Periphery. It looks like this:

Main Thread                                     Sub Thread
+------------------+                         +---------------------+
|                  |                         |                     |
| +-------------+  |  CPU cycles/sec queue   |                     |
| |            <------------------------------------+6809 CPU      |
| |             |  |                         |       +     ^       |
| |     GUI     |  |                         |       |     |       |
| |             |  | Display RAM write queue |    +--v-----+--+    |
| |  .--------------------------------------------+   Memory  |    |
| |  |          |  |                         |    +--+-----^--+    |
| |  |          |  |                         |       |     |       |
| |  |          |  |                         | +-----v-----+-----+ |
| |  |          |  |                         | |    Periphery    | |
| |  |          |  |     Keyboard queue      | |   MC6883 SAM    | |
| |  |          +--------------------------------->MC6821 PIA    | |
| |  |          |  |                         | |                 | |
| +--+-----^----+  |                         | |                 | |
|    |     |       |                         | +-----------------+ |
|    |     |       |                         |                     |
| +--v-----+----+  |                         |                     |
| |             |  |                         |                     |
| |   Display   |  |                         |                     |
| |             |  |                         |                     |
| +-------------+  |                         |                     |
+------------------+                         +---------------------+

performance

The current implementation is not really optimized.

With CPython there is round about 490.000 CPU cycles/sec. in console version. This is half as fast as the real Hardware.

With PyPy round about 6.900.000 - 8.000.000 CPU cycles/sec. In other words with PyPy it’s 8 times faster as the real Hardware.

e.g. The Dragon 32 6809 machine with a 14.31818 MHz crystal runs with: 0,895MHz (14,31818Mhz/16=0,895MHz) in other words: 895.000 CPU-cycles/sec.

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

...path/to/DragonPy$ python2 DragonPy_CLI.py benchmark
...path/to/DragonPy$ python3 DragonPy_CLI.py benchmark
...path/to/DragonPy$ pypy DragonPy_CLI.py benchmark
...path/to/DragonPy$ pypy3 DragonPy_CLI.py benchmark --loops 10

included Python modules:

python-pager Page output and find dimensions of console.

• Author: Anatoly Techtonik

• License: Public Domain

• Homepage: https://bitbucket.org/techtonik/python-pager/

• Stored here: /dragonpy/utils/pager.py

srecutils.py Motorola S-Record utilities

• Author: Gabriel Tremblay

• License: GNU GPL v2

• Homepage: https://github.com/gabtremblay/pysrec

• Stored here: /dragonpy/utils/srecord_utils.py

six Six is a Python 2 and 3 compatibility library.

• https://pypi-hypernode.com/pypi/six

• https://bitbucket.org/gutworth/six