[libre-riscv-dev] daily kan-ban update 08mar2020

[Luke Kenneth Casson Leighton]

On Fri, May 8, 2020 at 10:39 PM Jacob Lifshay <programmerjake at gmail.com> wrote:
>
> On Fri, May 8, 2020, 13:27 Yehowshua <yimmanuel3 at gatech.edu> wrote:
>
> > Litex also support ethernet which would require a $20 PHY, not great for a
> > low cost SBC.
>
>
> There are some inexpensive GbE PHYs using the GMII interface (what I think
> is what we are planning on using),

RGMII.  GMII is 8-bit TX, 8-bit RX (so around 26 pins total) where
RGMII is DDR and half the TX and RX pins.  you can see here
https://libre-soc.org/shakti/m_class/pinouts/


> mouser sells some for less than $2 each:
> https://www.mouser.com/ProductDetail/Intel/PEF7072HLV16-S-LLHN?qs=d5w0Orft5TofEDXuIkwIvA==

which  means in China it's well under $1

RT8192.

an alternative is an MCU Bus (AT/XT/ISA) and to use the DM9000.

https://libre-soc.org/shakti/m_class/peripheralschematics/

l.