On Fri, Nov 15, 2013 at 12:31 AM, Andrew Back <and...@abopen.com> wrote:

> Hi Stefan,
>
> On 22 October 2013 20:41, Stefan Kristiansson
> <stefan.kristians...@saunalahti.fi> wrote:
> > On Tue, Oct 22, 2013 at 2:55 PM, Andrew Back <and...@abopen.com> wrote:
> >>
> >> On 22 October 2013 11:53, Stefan Kristiansson
> >> <stefan.kristians...@saunalahti.fi> wrote:
> >> >
> >> > Something like this:
> >> >
> >> >
> http://www.thaieasyelec.net/index.php/Ethernet-Module/DP83848-Ethernet-Phy-Breakout-Board/p_179.html
> >> > would do it. It will still require a small bit of HDL hacking though,
> to
> >> > add
> >> > the ethernet mac core to the de0_nano SoC.
> >> > Drivers should be covered though.
> >>
> >> Would that hacking be akin to a minimal wiring exercise or a fair bit
> >> more involved?
> >>
> >
> > Basically just wiring and instantiation of the ethmac core.
> > For orpsocv3 this is perhaps not the whole truth, since there are no
> boards
> > using
> > ethmac yet, so a core description for it has to be made as well.
> > But it shouldn't be a huge task, and I'm sure you'd get well enough
> support
> > from us.
> >
> > Btw, the breakoutboard I linked to seems to be out of stock,
> > but I found a similar here:
> > http://www.wvshare.com/product/DP83848-Ethernet-Board.htm
>
> So the DP83848 PHY breakout board I ordered from Hong Kong has now
> arrived, and I was wondering where I should look to ascertain how to
> go about adding ethmac to ORPSoCv3 and to do the wiring.
>
> The board has TX0/1, RX 0/1, TX_EN, MDC, CRS, MDIO and OSCIN pins. I'm
> guessing I may need the SMII core also?
>
>
Not SMII, that's an RMII interface. I didn't realise that the board only
exposes that, not MII. That means you need a bit more work to get it working
than just wiring it up, but not much.
You need a trivial RMII/MII converter ontop of the ethmac.
I can dig out some code for taht for you some time next week,
but it's very simple, the difference between RMII and MII is basically
doubled
data rate for the TX/RX signals (50 MHz vs 25 MHz in 100Mbit mode) and
that RXDV and CRS share the same pin.

Stefan
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