[Coco] two other things..
cyouse at serialtechnologies.com
Wed Jul 9 16:10:25 EDT 2008
I'm not a uIP fan because of its rather unusual interface (the
application is responsible for buffering data in case of retransmission,
it's state-driven, etc.). It's meant for _very_ small uC environments,
and a Coco 3 w/ OS-9 and 512K of RAM doesn't really qualify. I'd be
much more comfortable with something more like the traditional socket
interface, in the form of a file manager. Don't sell the Coco short!
As for hardware, SiLabs makes a chip called the CP2200 which is an
integrated 10baseT MAC/PHY. Interestingly, it probably will require
very little in the way of bus interfacing to the Coco. Its only
drawback is that it has odd requirements on the magnetics, 1:2.5 turns
ratio on the transmit lines -- but that's just a minor annoyance rather
than a serious problem. I've got three of the chips and three
compatible jacks handy, so I'll give it a whirl.
On Wed, 2008-07-09 at 17:00 -0300, James Dessart wrote:
> On 7/9/08, Chuck Youse <cyouse at serialtechnologies.com> wrote:
> > But I really think the only thing that makes using NitrOS-9 today
> > somewhat problematic is its lack of Ethernet/IP support. I could
> > _totally_ use it as a workstation if it were networked. And no, SLIP
> > doesn't count (too slow!).
> I had been trying in the past to get ethernet going on the CoCo. My
> main problem was that my hardware design skills are next to
> non-existant. Added to that was the issue that at the time there were
> no decent compilers that would work on a modern host.
> However, there is now someone actively developing gcc6809, by the name
> of Brian Dominy. Support for any variant of OS9 is missing in the
> linker, however, and AFAIK, PIC code generation is also missing.
> However, if that were dealt with, uIP is a nice little TCP/IP stack
> that fits well inside 8K of RAM. I had managed to get it running
> within an ATmega8 processor with a small http server included.
> Ethernet hardware is pretty cheap these days, and a basic driver would
> probably be fine. uIP already contains AVR compatible C code for an
> RTL8019 controller. The RTL8091's address space is kinda large
> considering the CoCo's IO address footprint, however.
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