[Coco] Ethernet Port Cartridge for the Coco 3

[John W. Linville]

On Tue, Feb 05, 2013 at 09:44:10AM -0800, Steve Batson wrote:

> While some say that the CoCo is too slow to implement an ethernet
> interface with software to implement the TCP/IP stack on it (and I
> totally understand that), wouldn't it be possible to create a product
> that handled all of the Ethernet hardware as well as the networking
> stack and just transfer requests and responses to the coco when
> appropriate? For example, if software was doing a file transfer,
> couldn't the coco just pass the request  off to the controller and
> transfer the data at speeds that it can handle with the controller
> doing all of the heavy lifting and buffering as needed?

I will say categorically that there is _nothing_ preventing a CoCo from
being able to communicate via TCP/IP.  This is true either over serial
or via ethernet (provided the correct hardware), and also true whether
the networking code runs on the CoCo itself, on a wiznet or similar
device, or on a connected host (e.g. DriveWire).  At least one option
(serial port to DriveWire server) exists today already.  Running the
stack on the CoCo itself is really just a Simple Matter Of Programming.

Now, the practicalities of what might be done with such a stack
are real.  File transfers and simple "console" style access are the
most likely applications.  (FWIW, email and even the retrieval of HTML
pages are basically just file transfers.)

Also, running the stack on the CoCo itself would likely exert some
performance penalty on the CoCo.  So, such an option may further limit
what practical use you might get of the system.

> I know people of talked about a web browser for the coco too. I do
> think the graphics and resolution limits alone would make that not
> feasible even if the controller did all the hard work and just passed
> the page info to the coco, but I don't see why text based connections
> and file transfer type networking would be out of the question if
> the controller did all the stuff that the CoCo couldn't do efficiently.

As you say, the graphical display of web pages is at least impractical
on a CoCo.  Some subset of functionality might be available, including
limiting display to text only.  Unfortunately, even rather primitive
web pages often include code that executes on the local browser
nowadays...

> Let's say this was a feasible approach, why would this approach
> not be acceptable if it works and there's no other feasible way to
> do it? Better than not having the ability to do it :)

I'm sure it can be done.  I just have other things that are higher
on my list of priorities.  I presume that others are in the same boat
as me.

FWIW, I think that KA9Q networking package was available on the CoCo
(perhaps under OS-9) in the past.  If you are desperate for TCP/IP
file transfers running over the serial port, you might try to revive
that code. :-)

John
-- 
John W. Linville		Someday the world will need a hero, and you
linville at tuxdriver.com			might be all we have.  Be ready.