[Coco] Using DriveWire to write network software

[Mark D. Overholser]

On 27-Mar-17 08:36, Aaron Wolfe wrote:
> Hi,
>
> When I wrote the drivewire tcp stuff, it was really just a proof of
> concept and not super well thought out.  Shortly after that I learned
> about chips like the wiznet series, and it seemed that someone would
> be connecting something like that to a coco in the near future so we
> didn't put much work into those things in DriveWire.  We actually
> wrote the client side stuff for os9 with the idea in mind that someday
> they would be used with a "real" or alternative IP stack.
>

I was wondering if anyone else had thought about the WizNet W5100 device 
for the CoCo...

In the Apple ][ realm, the latest Ethernet card, The Uthernet II uses 
the WizNet W5100, but Only in the "Indirect Bus Interface mode", which 
means it's limited to Four Bytes in the I/O Space.



> Would it make sense to revisit that idea?  There are many more options
> now than a few years ago, but the basic idea of "ip stack on a chip"
> still seems like a nice solution for older hardware.
>

Yes, it seems to be the best way to go.  So far.


> Even if there isn't a hardware solution at present, most if not all of
> the functionality could be duplicated in a "drivewire-like" server and
> driver shims on the coco side that did serial comms like dw rather
> than the hardware SPI or other interface there would be in a chip
> based solution.
> Basically, rather than the essentially proprietary and not very well
> designed DriveWire protocol, we could use some industry standard
> chipset.  I'd be willing to put in some time to make some example code
> or a proof of concept server if people are interested.  Or if somebody
> wants to get an IP stack chip connected to a coco, it's not even
> needed.  For the FPGA side of things, I believe you have SPI already
> on the altera boards so an adapter that used the same ip chip might be
> simple to add, and the same software could work with both.
>
> Here is one example, but there are lots.  Some use a standard Hayes
> sort of command set, that would be super simple to hack together as a
> server out of things Drivewire already does.
>
> https://www.sparkfun.com/datasheets/DevTools/Arduino/W5100_Datasheet_v1_1_6.pdf
>
> -Aaron
>

It should be very possible to put a WizNet W5100 Module on a CoCo Cart 
and map it right into the Cartridge Space in "Direct Bus Interface 
mode"...  That will make the Code Less Complicated than using the 
"Indirect Bus Interface mode".



MarkO