[Coco] Ethernet status (uIP/Contiki)

[James Dessart]

Here's the status on the ethernet adaptor I'm designing for the CoCo, in
case anyone wants to know where I am. I've got an AVR processor now, an
ATmega8, and since the PacketWhacker (from http://www.edtp.com/) is used
in the AVR implementation of uIP (the TCP/IP stack at the heart of
Contiki) I'm going to get it going with my mega8 as a baseline.

Once this is done, I have a design for the CoCo version of the card
that'll hopefully work. I'm a novice when it comes to electronics, so I'm
not sure my design is any good, or even optimal. The design is somewhat
more complicated than it might need to be, so that I can cram a 5-bit
address space into 4 bytes of CoCo IO space. One is a register selector,
another writes and reads from the selected register, and the last two are
the in/out ports of the device. I sent my design off to someone to check,
but haven't heard back from them. If someone here's willing to take a
look, it'd be very much appreciated.

I'll have to breadboard the device, after buying the necessary standard
TTLs. Unfortunately, I don't have much in the way of CoCo card prototyping
tools. Someone on the list had said they'd prepare me a board for that,
and I can't, for the life of me, remember who that was. I lost all my
email from that time, so I can't check either.

In the end, for those wanting to put one of these board together yourself,
the PacketWhacker costs $35 ($25 for the partly assembled version, which
is a PITA...). I imagine the TTLs wont be too expensive, so you're
probably looking at a total part cost of $45 at the most.

I'm hoping that the coco gcc port can handle the uIP code without dying,
which might be a bit shady. The compiler has some rough edges and I've had
some abrasions from it already. :) (stdarg support isn't)

I'd like to do this in OS-9, but right now the compiler can't do PIC code.
So it'll be a standalone RS-DOS app at first, maybe with an httpd server
as the application. If and when I get it working, I'll try to post a URL
so you guys can give it a try. :)

James