Interconnecting 2 zodiac FX boards through SPI

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pjm

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Interconnecting 2 zodiac FX boards through SPI
« on: March 31, 2017, 09:14:34 PM »
Hello everyone!

We are very interested to buy several zodiac FX boards for research and educational purposes within our university, but we have a small question regarding the zodiac FX boards. The number of ethernet ports on a single board is quite limited (4 ports), and we were wondering if it is possible to interconnect 2 boards through the SPI port to create a single 8-port board?

This question has been asked before, and according to the kickstarter website this should be possible:
https://www.kickstarter.com/projects/northboundnetworks/zodiac-fx-the-worlds-smallest-openflow-sdn-switch/posts/1308104/comments

Could anyone confirm that this works? And if so, provide details on how the interconnection should be made? Any recommendations about suitable SPI cables is also very welcome!

Apart from this, does anybody know how much Ampere is needed for a single board?

Many thanks in advance and keep up the excellent work!

Kind regards,
Pieter-Jan

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pjm

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Re: Interconnecting 2 zodiac FX boards through SPI
« Reply #1 on: March 31, 2017, 09:21:24 PM »
Just found out that this thread is similar:
http://forums.northboundnetworks.com/index.php?topic=97.msg294#msg294

Any updates regarding the possibilities for stacking?

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Paul Zanna

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Re: Interconnecting 2 zodiac FX boards through SPI
« Reply #2 on: March 31, 2017, 09:38:35 PM »
Hi Pieter-Jan,

Your timing is impeccable, we will be releasing a stacking kit next month that will include all the hardware required to join 2 Zodiac FX switches together and create an 8 port switch.

Stay tuned!

Regards,
Paul

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relder001

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Re: Interconnecting 2 zodiac FX boards through SPI
« Reply #3 on: May 19, 2017, 11:11:30 PM »
I am new on the forum, please excuse any missteps  :-[

Is or are there any updates on the topic of interconnecting 2 FX boards?

I just received my two dev/test boards and super excited to interconnect them (for a very real field / test environment).

Thanks,

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Paul Zanna

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Re: Interconnecting 2 zodiac FX boards through SPI
« Reply #4 on: May 21, 2017, 09:43:12 PM »
We have spent many months looking into using the SPI connectors on the Zodiac FX to join 2 boards together and thereby creating a single 8 port device. Unfortunately I have come to the conclusion that the CPU is just not powerful enough and the SPI interface is not fast enough to allow a usable solution. :( The best we could manage was a couple of Mbps and even then it wasn't very reliable given everything else the CPU was trying to do. So at this point I'm going to have to park the idea for the time being, but I'm more then happy to support anyone else that may be interested in giving it a try. Just let me know and I'll share everything we have tried so far, thanks for your understanding.

Regards,
Paul

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relder001

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Re: Interconnecting 2 zodiac FX boards through SPI
« Reply #5 on: May 23, 2017, 05:15:56 AM »
Ah, fair enough.

Thank you for the feedback, and I agree the research I've done led me to wonder how the SPI interface could support it.
This is likely a noob question - but I did notice that the switch chip does have a 1Gb port.  The question I have, is this port a.) used by the processor or b.) not pinned out?

Thank you again,

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Paul Zanna

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Re: Interconnecting 2 zodiac FX boards through SPI
« Reply #6 on: May 26, 2017, 01:21:19 PM »
The 5th port on the switch is connected directly to the CPU for processing incoming OpenFlow packets and to talk to the controller.

Regards,
Paul