[Coco] CUBIX on the CoCo?

[Dave Dunfield]

>Hello Dave:

Hi James,

>As far as I know no one has ported Cubix to the Coco or at least the 
>Coco 3. I looked into doing a port to the Coco3. Several areas that 
>would require a deal of work. Since there are plenty of Coco disk 
>controllers availble to most Coco users, the disk driver would have 
>to be written for the WD1793/1773/2793 chips. Also the I/O range 
>moved to $FF00-$FFEF. Finally there is the GIME chip on the Coco 
>3. 
>
>While not impossible, it does entail a bit of work and time. Thanks 
>for  the link as I too  have an older copy. Maybe I can look at the 
>latest and see just  how complex a task it will be. Currently I have a 
>major home project working now that is taking up a bunch of my 
>free time.

CUBIX was designed from the very beginning to be quite portable. All
interface to hardware is through a clearly defined set of drivers,
which are separate enough that you can often port CUBIX just by changing
the drivers and initial vectors in the ROM image (a separate block at
the end). There is also no absolute memory requirements (although if
you don't have RAM at 2000 you will have to rebuild all of the system
utilities and application software to match your memory map).

To get it running, you need only provide sector read/write for the
block device, and character read/write for the console and other stream
oriented devices. Although CUBIX was designed to go into ROM, and likes
to control the interrupt vectors, even that is not a hard requirement,
as long as you can redirect the vectors into CUBIX under whatever host
environment you have. (The only vector the OS itself really needs is
SWI which is the System Service Request instruction - all others
are initially established by the driver supplied init function, and
need not be used unless the drivers require it).

Agreed that there may be some work to enhance the screen editors,
languages etc. to make full use of the hardware available on the CoCo,
however I wouldn't think a simple serial TTY interface and basic disk
I/O would be terribly difficult, especially if anyone has driver code
already lying around for these functions on the CoCo it shouldn't be
difficult at all.

(It would be cool for example to use the CoCo graphics to do an actual
APL character set for Micro-APL - but this is not necessary to use it,
as it was designed to work with ASCII characters).

If you do at some point have some time and would like to work together
to get it up and running, please give me a shout. I will stay attached
to this list as long as the traffic does not prove too high, but you
can always reach me via the contact information on my site.

FWIW, until the past couple of years, you could not experience CUBIX
unless you either built a system to match mine, or ported it to your
hardware - about a year or so ago, I wrote a simulator for my original
CUBIX machine, so you can easily check it out on a PC if you like.

(While getting it up and running on the simulator, I discovered a couple
of latent bugs which had not been apparent on "the real metal" - hence
the updated release this year).

Regards,
Dave

-- 
dave04a (at)    Dave Dunfield
dunfield (dot)  Firmware development services & tools: www.dunfield.com
com             Collector of vintage computing equipment:
                http://www.parse.com/~ddunfield/museum/index.html