Re: Ethernet over SPI driver for ENC424J600

[Alex Schuilenburg <alexs at ecoscentric dot com>]

Hi Ilija


John Dallaway wrote on 2009-10-26 09:05:
> Hi Ilija
>
> Ilija Stanislevik wrote:
>
>   
>> Dear fellows,
>>
>> I use this opportunity to announce our development project. It is a
>> driver for Microchip's ENC424J600 Ethernet controller.
>>
>> My company's goal is to obtain a low level Ethernet driver which will
>> use standard SPI support to communicate with the Ethernet chip. The
>> development is underway on STM3210E-EVAL board. We will be glad if we
>> succeed to make it independent from platform and SPI hardware.
>>
>> Further, we plan to contribute the result of this development, as
>> proposed in http://ecos.sourceware.org/contrib.html. Please advise us on
>> the next step in this direction.
>>     
>
> This is great news. Thank you for letting the eCos community know of
> your plans at an early stage.
>
> This driver could be useful for many eCos developers who need to add
> ethernet to an existing hardware design. I note that Microchip offers a
> daughter board which includes the (similar) ENC624J600 and should make
> it easy for others to start experimenting with these parts:
>
> http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1406&dDocName=en543132
>
> Are you intending to use lwIP or the FreeBSD TCP/IP stack in your
> project? Regardless, I would encourage you to verify correct operation
> with Simon Kallweit's port of lwIP 1.3.1:
>
>   http://download.westlicht.ch/
>
> lwIP is a good fit for eCos and I hope lwIP 1.3.1 will be integrated in
> eCos CVS soon.
>   
I think it is fair to advise you of the risks involved in using the
newer lwIP 1.3.1 stack and of more stable options available to you when
developing new code for eCos.  Since you are developing a new device
driver, I suggest you initially stick with the FreeBSD port (and
optionally older lwIP port) which are known to work reliably, rather
than do your initial development on the newer lwIP port which is still
undergoing testing. That way at least you will ensure you are debugging
your own code initially, rather than also somebody else's.

Once you are happy with the stability of the your device driver, please
also test it against Simon's lwIP 1.3.1 port as well since it obviously
needs testers and it will most likely replace the older lwIP stack. 

Please note that I am not suggesting that Simon's 1.3.1 port is unstable
or broken in any way, just that it is still relatively new and unknown
and that you ought to be aware of this when choosing which tcpip stack
to initially test your driver against.

Thanks for your notice and we look forward to seeing your contribution soon.

-- Alex Schuilenburg

Managing Director/CEO                                eCosCentric Limited
www.ecoscentric.com