viola_palimo
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Joined: Sun Mar 04, 2012 8:42 am

Re: PoE via the GPIO pins?

Sun Mar 04, 2012 9:01 am

Quick question:

I read in the FAQ that there have been several requests for PoE and that the project is looking into it for future releases. I'm thinking though, since you are able to power the device via some of the GPIO pins wouldn't is be possible to just make a GPIO-add-on-board such as the ones listed in the WiKi (the Gert-board etc.) that will sit on top of the RasPi and simply do the PoE-feed.

I'm seeing something like this http://www.acceed.com/pdf_catalog/rayon ... atalog.pdf could be "turned into" such an add-on. That would be a great add-on, probably fairly easy to put together for someone with a little electro-mechanical knowledge (and equipment).

I would be willing to fund development (to a certain extent). Anyone?

plugwash
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Re: PoE via the GPIO pins?

Sun Mar 04, 2012 10:18 am

A PoE addon would need two connections to the Pi, one for ethernet and one for power, the ethernet connection would have to be made via the Pis ethernet port, the power connection can be made via either the micro-usb power inlet or the GPIO header whichever is more mechanically convenient.

arm2
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Re: PoE via the GPIO pins?

Sun Mar 04, 2012 9:56 pm

I don't understand the http://www.acceed.com device the minimum connection I'd expect would be the four active ethernet(with power) input line and four active ethernet(without power) output lines plus 5V and earth.

Also I'm not sure that you can use the type of connector they have and comply with ethernet standards.

But going back to the basic idea. I'm hoping that we can commercially produce one, though I will have to find a designer as this is outside our area of expertise.

Morphology
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Re: PoE via the GPIO pins?

Thu Apr 05, 2012 8:35 am

sorry to resurrect a slightly decayed thread, but i think what you need is one of these:

http://www.silvertel.com/DataS.....Sv2-22.pdf

It handles the Ethernet side of things, and splits out a 5v rail, which could be interfaced to the GPIO. They seem to be about $10

Morph

arm2
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Re: PoE via the GPIO pins?

Sun Apr 08, 2012 8:41 pm

Morphology said:


sorry to resurrect a slightly decayed thread, but i think what you need is one of these:

http://www.silvertel.com/DataS.....Sv2-22.pdf

It handles the Ethernet side of things, and splits out a 5v rail, which could be interfaced to the GPIO. They seem to be about $10


Looking at the pinouts and Fiq3 that appears to be only part of the circuitry needed:-(

By the time the other electronics, sockets and (case if necessary) are added the ready made commercial offerings look better.

daidem
Posts: 1
Joined: Mon Apr 09, 2012 10:28 am

Re: PoE via the GPIO pins?

Mon Apr 09, 2012 12:34 pm

You could just hack a cable together and split the wires out to micro USB cable.

grahamed
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Joined: Mon Jan 30, 2012 7:01 pm

Re: PoE via the GPIO pins?

Mon Apr 09, 2012 5:20 pm

or you could buy one of these

http://www.ebay.co.uk/itm/PoE-.....3124wt_903

for a short wire just insert 5V at the other end, or for a longer wire insert more and regulate it at the pi end. In either case you need to to sort the input to the pi.

plugwash
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Re: PoE via the GPIO pins?

Mon Apr 09, 2012 9:41 pm

Morphology said:


sorry to resurrect a slightly decayed thread, but i think what you need is one of these:

http://www.silvertel.com/DataS.....Sv2-22.pdf

It handles the Ethernet side of things,


Unfortunately it assumes your deisgn already contains a POE capable set of magnetics that you can connect the module to. The Pi doesn't so you would have to insert a second set of magnetics between the ethernet cable, the Pi and that module.

If you do want to use proper POE with a Pi then I think your best bet is something like http://www.ebay.co.uk/itm/TP-L.....20c42124ae

AmosK
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Joined: Fri Aug 10, 2012 5:27 pm

Re: PoE via the GPIO pins?

Fri Aug 10, 2012 6:06 pm

I agree that using a daughter board on top of the RPi that uses the GPIO to power the board is the cleanest way to do this. Consider using an Adafruit prototyping plate for $16 and a 2-port ethernet passthrough port with PoE breakout ($13), and perhaps a custom breakout board for the .050" pinout offset on the RJ45 block. Then use the $10 PoE DC-DC converter that Morphology mentioned...

$16 - Daughter board:http://adafruit.com/products/801
$13 - Two port RJ45: http://www.te.com/catalog/pn/en/1-66101 ... -6610128-1
$10 - http://www.silvertel.com/poe_products.htm

Seems easy enough to me :D

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