The "Dunfield 6809" is a portable computer that I designed in the mid
1980s. This was a complete system design. It does not run an "off the
shelf" operating system, but uses CUBIX, a system I developed at the
same time.

This package is a simulator for the "Dunfield 6809" homebuilt, which allows
you to mount and access diskette images and run the software on your PC,
exactly as you would on the physical 6809 based computer.

Note: This is not a "pretty" graphical simulator. It is mainly intended
to provide an experience of my machine from the point of view that you are
sitting in front of it and viewing the internal text based screen. For this
reason the simulation runs in a TEXT mode screen. The large fixed pitch
characters of text mode provide a fairly accurate reproduction of the "feel"
of using the internal text video display.

I have not yet written extensive documentation for the simulator, however
there is fairly decent online help available from within it.

Being a text mode program, the simulator and tools are best used from a
command line prompt (If you are not comfortable with a command line prompt
and text mode screens, you will probably not find this material very useful,
and you definately not have liked the D6809 - or any other computer from
this time period).

-- Simulator files --
D6809.COM   - Dunfield 6809 simulator
D6809.HLP   - Help file for ""
D6809.ROM   - System ROM image containing CUBIX OS
DDI.COM     - Utility to create/manipulate disk image files
GETDOCS.BAT - Batch file to Import documents to PC files
CUBIX.DDI   - Cubix utilities disk image
CDOC1.DDI   - Cubix system documentation disk image
CDOC2.DDI   - Cubix languages documentation disk image

The CUBIX documentation files are provided in a CUBIX format disk image.
You can mount CDOC1.DDI and CDOC2.DDI as disks on the simulator, and
access the documentation under CUBIX, exactly as an actual CUBIX user
would have.

[Hint: Normally, you would mount the CUBIX utilities disk CUBIX.DDI as
 drive A, and the documentation disk as drive B - this way you will have
 access to the CUBIX utilities for viewing text files]

I have also provided a PC GETDOCS command which makes use of the included
DDI utility to extract the documents from the disk images to standard PC
files, where you can view them with any PC based text editor.
Simply run:
     GETDOCS
And the .TXT files will be created in the current directory.

--CUBIX OS documentation files--
CUBIX.TXT   - CUBIX Users Guide
SYSPROG.TXT - CUBIX System Programming Manual
PORT.TXT    - CUBIX System Porting Guide
ASM.TXT     - 6809 Assembler
ASP.TXT     - Assembly Source Preprocessor
BASIC.TXT   - Micro-BASIC
ED.TXT      - Simple editor
EDT.TXT     - More powerful editor
MAPL.TXT    - Micro-APL
MICROC.TXT  - Micro-C
RAID.TXT    - Debugger
SIM80.TXT   - 8080 Simulator
TTY.TXT     - TTY package
FORTH.TXT   - Notes on 6809 FORTH implementation
MBASIC.TXT  - Notes on 8080 BASIC implementation


Booting the Dunfield 6809
-------------------------
The D6809 does not actually boot from disk. It simply begins running from
it's internal ROM. Therefore, just starting the simulator will cause the
CUBIX OS to start up.

One of the first things CUBIX does, is to look for a file called STARTUP.*
and execute it if found. In order to avoid a disk error, you should have a
disk mounted in drive A: when CUBIX boots. You can do this with the command
line R=/W= options, or via the F7 STOP mode command within the simulator.

Note that if you like, you can use the C= option to redirect the virtual
6551 serial ports to a physical PC serial port. You can then use the
SET CONSOLE command within CUBIX to redirect console I/O to the serial
port, and communicate with it via an external terminal, which is how some
other CUBIX systems that I have built over the years worked.

NOTES:
------
- There are no files in the [MAIN] directory of the working disk. Use
  'DIR [*]' to see all the files on the disk (You will probably want to
  press F6 first to get slow console scrolling).

- There is minimal online help for most CUBIX commands (type HELP), 
  however much more information is available in the documentation files.
  Most commands will also output a brief usage summary if invoked with an
  argument of '?'.

- You can mount drives "on the fly" in the simulator by pressing F3 to stop
  the simulation, then F7 to access the disk mount function. After selecting
  a drive and diskette image, press 'G' and the simulation will continue.

- Most of the files on the distribution "diskettes" are Read only, which
  is how the original master disks were created. You can use the following
  steps to make a working disk with Read/Write files ('>'=PC command,
  '*'=D6809/CUBIX command):
     >DDI WORKDISK FORMAT            <= Create blank disk: FORMAT.DDI
     >D6809 R=CUBIX W=WORKDISK -D    <= Run simulator, mount disks (fast)
     *COPY A:[*]*.* B:[*]            <= Copy files but not protections
  WORKDISK.DDI will now have all of the files from the original system
  disk, however they will have full permissions (RWED).

- There are two versions of the ED editor - ED.EXE is the version for the
  Portable 6809 computer. ED100.EXE is the VT100 version. Refer to the
  simulator help for PC->D6809 keyboard mapping, and use ^0 (ALT-0) to
  bring up a help screen in ED showing the D6809 keys used.

- Key mapping for the TTY library (used by EDT) is:
  Function               D6809       PC
  -------------------------------------
  Cursor Up               Up         Up
  Cursor Down             Down       Down
  Cursor Left             Left       Left
  Cursor Right            Right      Right
  Page Up                 Rvrse      PgUp
  Page Down               Fwd        PgDn
  Page Left               ^Left      ^Left
  Page Right              ^Right     ^Right
  Home                    ^Up        Home
  End                     ^Down      End
  Delete Char             Blank      Backspace
  Delete Previous         ^Blank     ^Backspace
  Clear Screen            ^X         ^X
  Function 1-9            ^1-^9      Alt1-Alt9
  Function 10             ^0         Alt0
  Function 11             ^=         Ctrl=
  Function 12             ^-         Ctrl-
  Function 13             ^Rvrse     Insert
  Function 14             ^Fwd       Delete
  Function 15             ^Enter     ^Enter

- If you build a CUBIX compatible computer (eveything you need is available
  on my site), you can write the disk images to physical disks that you can
  use on the machine with my ImageDisk program (also on my site).
  EG: Use the command: bin2imd cubix.ddi cubix /2 n=40 sm=0-8 dm=5 ss=512
  to convert the CUBIX.DDI raw simulator image into CUBIX.IMD format image
  which can be written to a physical diskette with ImageDisk.

A complete "package" on the Dunfield 6809 computer which includes, photos,
documentation, reference material and the complete CUBIX source code is
available on my web site:

    http://www.dunfield.com
    Scroll down to the "old computer guy" at the bottom of the page and
    click on him - this will take you to my classic computer collection.
    Select the entry under "Homebuilts" called "D6809 Portable".


Dunfield Development Services (DDS) offers software and firmware
development services specializing in systems and embedded applications.
For more information, visit: http://www.dunfield.com
