Page 1 of 5

POE support on Rpi 3

Posted: Sun Mar 15, 2015 7:14 pm
by jsquaredz
Would like to suggest that the RPI 3 gets Power Over Ethernet (POE) support in the next iteration. Being able to power over the ethernet port adds an additional stream of use cases for things I can build with this PI without being tethered to a mains and wall wart. Thanks for your consideration.

Re: POE support on Rpi 3

Posted: Sun Mar 15, 2015 8:13 pm
by mahjongg
In all previous posts that mentioned wanting POE, it has been made abundantly clear that the small percentage of people who want POE does not make up for the majority of people who find this add-on worthless, but nevertheless need to pay for it if its implemented as standard. This and the fact that POE can easily be added afterward makes it a no-brainer that POE will NOT be added to any standard version of any PI, the costs are simply too great for the benefits, even for a fictitious PI3. Its against all that made the PI a success to do so.

Re: POE support on Rpi 3

Posted: Sun Mar 15, 2015 10:06 pm
by W. H. Heydt
I suspect that an on-chip RTC would have wider application, especially if a battery to keep it going when the system is unpowered was up to the owner to supply. The real incremental cost would be a connector or holder for the battery.

On the flip side, the other feature I'd really like would probably have even less support than PoE, and that's a native SATA port.

Re: POE support on Rpi 3

Posted: Sun Mar 15, 2015 10:18 pm
by rpiswag
While where on the topic of a fictitious Raspberry Pi 3 or as I would call it the Raspberry 2B+. I think it should have a dedicated ethernet and not have to share the bus with usb. A faster cpu with more cores but it would be better with a more powerful gpu. That GPU hasn't been updated even from the original pi model B. It would be great it a new pi with better specs by 2017-2018. I wonder what else this futuristic and fictitious pi should have hum........ :ugeek:

Re: POE support on Rpi 3

Posted: Sun Mar 15, 2015 10:31 pm
by riklaunim
rpiswag wrote:While where on the topic of a fictitious Raspberry Pi 3 or as I would call it the Raspberry 2B+. I think it should have a dedicated ethernet and not have to share the bus with usb. A faster cpu with more cores but it would be better with a more powerful gpu. That GPU hasn't been updated even from the original pi model B. It would be great it a new pi with better specs by 2017-2018. I wonder what else this futuristic and fictitious pi should have hum........ :ugeek:
They didn't upgraded the GPU to retain better compatibility with previous version. To offer non-USB Ethernet and better GPU they would have to use different SoC, which they didn't want to do for v2. But there is still Banana Pi and many other Allwinner A20 boards (and other SoCs too) that offer such features. There are even x86 Bay Trail dongles showing up.

Re: POE support on Rpi 3

Posted: Sun Mar 15, 2015 10:59 pm
by plugwash
The BCM2835 was somewhat unbalanced for general purpose computing, the arm core was relatively weak compared to the rest of the hardware. On the other hand when we look at the 2836 the most pressing limitations are elsewhere. IMO doing another CPU core upgrade without also making fairly radical changes elsewhere (memory controller, IO, possiblly GPU) would be pretty pointless.

Like others here I find PoE on a future pi highly implausible, add up the cost of the beefier transformers, the control chip and the isolated DC-DC converters and you end up with something that adds a substantial chunk to the BoM cost of something like the Pi for an application that is outside the pi's core remit.

SATA strikes me as plausible but unlikely.

All of the above is based on my own thoughts, I have no idea if the raspberry pi foundation have started working on pi3 or what their plans are.

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 12:26 am
by DougieLawson
If I had to choose between PoE or SATA or USB3.0/gigabit ethernet. I'd choose USB3.0/gigabit ethernet every time.

USB2.0 to SATA is good enough, USB3.0 to SATA would be even better
PoE is a complete non-starter, I'm not planning to re-wire my house and I'm happy using WiFi.

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 2:03 am
by W. H. Heydt
plugwash wrote: All of the above is based on my own thoughts, I have no idea if the raspberry pi foundation have started working on pi3 or what their plans are.
I would startled if there are people at the RPF that *aren't* thinking about the Pi3. Probably not doing anything serious yet, as it's probably 3 to 5 years out (not the 2 to 3 as suggested earlier in this thread). The RPF has, basically, two choices. One is to find another chip with the features they will enhance the Pi for the RPFs mission, or to look at the budget to see if there is a way to get what they think as a major improvement made for them.

As it is, I can't really see going to more than 4 cores unless there is a radical change in the sorts of workloads that students are going to use on the Pi...say if a really, really nifty piece of software comes along that fits the educational remit that will multithread and use all the compute cores it can get.

Ignoring economics for the moment, finding a way to crank up the clock speed on the VC4 to wring more performance out of it (which would probably require a die-shrink, an expensive proposition) and coupling that with faster compute cores, perhaps moving to A15 cores, would give a large jump in capability. Beyond that, gaining a native Ethernet bus (even at 100Mb/s) would be good. If the native clock speed goes above about 1.2 to 1.5GHz, being able to shift to 2GB RAM would become a good idea. The only other *major* upgrade I could see on the next iteration might be to go to 64bit cores, but I think that is much more likely for a Pi4 in 7 to 10 years.

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 2:11 am
by W. H. Heydt
DougieLawson wrote:If I had to choose between PoE or SATA or USB3.0/gigabit ethernet. I'd choose USB3.0/gigabit ethernet every time.

USB2.0 to SATA is good enough, USB3.0 to SATA would be even better
PoE is a complete non-starter, I'm not planning to re-wire my house and I'm happy using WiFi.
We're going to have to agree to disagree on some of those points. USB2 = 480Mb/s. SATA1 = 1.5Gb/s. SATA2 = 3Gb/s. SATA3 = 6Gb/s. The A10/A20 boards that have SATA are using SATA2. Even without competing with other devices, USB2 really can't handle any SATA device effectively.

I don't see a real need for Gigabit Ethernet. You can't get data off the storage devices that are being used now, either the SD card or a USB attached mass storage device, to need gigabit. Plus, you're only going to being anything at that speed locally. It'll be a long time before gigabit broadband becomes anything even faintly resembling "common".

Separating the Ethernet onto its own bus--even at 100Mb/s--is probably a goal to go for, though.

I do agree with you about PoE.

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 7:25 am
by rpdom
DougieLawson wrote:If I had to choose between PoE or SATA or USB3.0/gigabit ethernet. I'd choose USB3.0/gigabit ethernet every time.
USB2.0 to SATA is good enough, USB3.0 to SATA would be even better
At a minimum I'd chose a 100Mb ethernet port that doesn't run through USB. Then possibly two native USB 2.0 (not OTG) ports on the SoC.
I doubt USB3.0 is worth it for CPUs at this level.
A SATA port would be handy, even if it didn't run at high speed, but I'm not too bothered. Currently using a USB-SATA adaptor and that's good enough for me.
PoE is a complete non-starter, I'm not planning to re-wire my house and I'm happy using WiFi.
I did rewire my house. :D
I'm not happy with wifi (apart from the Pi in my garage).
I don't need PoE. That would be a complete waste.

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 9:28 am
by Crutcher
I have to agree that a higher performance mass storage interface such as SATA 2 or pcie for connecting a disk and/or SSD would be be the best upgrade for the next pi design. The current SD card system is low performance and unreliable. I believe it is the most limiting factor for many applications. SD cards don't really seemed to be designed to be used as the main working storage for a general purpose computer system. USB 2.0 storage systems are great for expanding storage capacity but have limited perfomance.

Bringing PoE to the masses!

Posted: Mon Mar 16, 2015 10:42 am
by Bruny
DougieLawson wrote:PoE is a complete non-starter, I'm not planning to re-wire my house and I'm happy using WiFi.
I would be happy using PoE enabled powerline adapter :idea:

Re: Bringing PoE to the masses!

Posted: Mon Mar 16, 2015 12:05 pm
by DougieLawson
Bruny wrote:
DougieLawson wrote:PoE is a complete non-starter, I'm not planning to re-wire my house and I'm happy using WiFi.
I would be happy using PoE enabled powerline adapter :idea:
That's the optimal solution and one that folk are already using.

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 12:26 pm
by pluggy
I'd suspect that as many Pi's are using wireless out there as ethernet now. POE is questionable for anything these days, flood wired legacy ethernet installations notwithstanding. If it were me I'd put built in wifi system in the next one. It would help with the vast array of wifi problems we get on here. It isn't difficult to get POE (maybe not official POE at 48v) if you wanted it doing it by hand.

I'd think that many people on here wouldn't have a clue what POE is.

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 1:08 pm
by gkreidl
Crutcher wrote:I have to agree that a higher performance mass storage interface such as SATA 2 or pcie for connecting a disk and/or SSD would be be the best upgrade for the next pi design. The current SD card system is low performance and unreliable. I believe it is the most limiting factor for many applications. SD cards don't really seemed to be designed to be used as the main working storage for a general purpose computer system. USB 2.0 storage systems are great for expanding storage capacity but have limited perfomance.
Do you really think that a small computer like the RPi needs more than 25-30 MB/sec data throughput to mass memory? That's what I get from my USB HDDs (I've moved the root FS to HDDs).

What does Taiwan and France know that the USA won’t recogniz

Posted: Mon Mar 16, 2015 1:42 pm
by Bruny
pluggy wrote:I'd suspect that as many Pi's are using wireless out there as ethernet now. POE is questionable for anything these days, flood wired legacy ethernet installations notwithstanding. If it were me I'd put built in wifi system in the next one. It would help with the vast array of wifi problems we get on here. It isn't difficult to get POE (maybe not official POE at 48v) if you wanted it doing it by hand.

I'd think that many people on here wouldn't have a clue what POE is.
wifi is questionable in some schools? It is unlikely that schools will use some unofficial power method instead off many always powered adapters :!:

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 2:20 pm
by pluggy
I work part time in a school,The existing ethernet has network ports that have failed over the years (usually builders handiwork drilling & cutting cables). Getting them working again isn't considered a priority due to the increased use of laptops and tablets. The flood wired ethernet that was all the rage in the 90's is considered a 'has been' technology.

We won't mention the 'bodged' connections that use the spare connectors for a second ethernet port and POE just isn't an option.

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 8:32 pm
by beta-tester
RPi3 ... ?! did i missed something :o
if i can wish something, for me,
1. RTC, because of if no network not time (specially on RPi model A)
2. Hardware acceleration for H.265
3. Giga Ethernet + WakeUpOn LAN + PXE boot
4. SATA + USB 3.
5. I2C port, that is able to work in multi master/slave environment
6. more modern CPU, more modern GPU, more GHz
7. a more common (display) port to connect LCD screen panels directly
...
and finally PoE.

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 9:12 pm
by gkreidl
beta-tester wrote:RPi3 ... ?! did i missed something :o
if i can wish something, for me,
1. RTC, because of if no network not time (specially on RPi model A)
2. Hardware acceleration for H.265
3. Giga Ethernet + WakeUpOn LAN + PXE boot
4. SATA + USB 3.
5. I2C port, that is able to work in multi master/slave environment
6. more modern CPU, more modern GPU, more GHz
7. a more common (display) port to connect LCD screen panels directly
...
and finally PoE.
... and a refrigerator and coffee cooker built in. And all that for 25$.

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 9:20 pm
by mikerr
W. H. Heydt wrote: I don't see a real need for Gigabit Ethernet. You can't get data off the storage devices that are being used now, either the SD card or a USB attached mass storage device, to need gigabit.
The USB3 gigabit adaptor currently attached to my Pi says different.
http://www.raspberrypi.org/forums/viewt ... 5&start=25
It's TWICE as fast for data transfers as the built in ethernet.

(gigabit speeds ? well not maxed out, or even 30%, but beats a standard pi by a factor of 2, worth it for me)

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 9:46 pm
by eriktheitalian
my priority:

Important:
1) videocore driver (http://dri.freedesktop.org/wiki/VC4/)
2) usb 3.0 ( lots of usb 3.0 hardware not stable like usb 2.0. we need stable usb 3.0 )
And more:
3) power input with jack. not micro usb plug. or alternative power input with micro usb input.
4) optical spdif.
5) 5.1 or 7.1 analog audio output. ( if this possible pls dont use realtek codec )
6) h265 decoding.

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 10:21 pm
by riklaunim
eriktheitalian wrote:my priority:

Important:
1) videocore driver (http://dri.freedesktop.org/wiki/VC4/)
2) usb 3.0 ( lots of usb 3.0 hardware not stable like usb 2.0. we need stable usb 3.0 )
Only some high end ARM SoCs implement USB3 (and all Intel/AMD low power SoCs?) so 2 would quite likely already exclude 1 and use a SoC with high tier Mali or nVidia GPU. As those high end SoCs aren't cheap you would just get a relatively expensive board (some are already available). New technologies is not Raspberry Pi goal ;)

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 10:41 pm
by scidata
1 or 2 buttons and 1 or 2 LEDs connected to GPIO. This would allow the Pi to do something right out of the box, thereby capturing the attention of the Internet generation.

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 11:15 pm
by chgus
plugwash wrote: Like others here I find PoE on a future pi highly implausible, add up the cost of the beefier transformers, the control chip and the isolated DC-DC converters and you end up with something that adds a substantial chunk to the BoM cost of something like the Pi for an application that is outside the pi's core remit.
PoE is convenient but costly. Have anyone considered optional PoE module -ready board? The arduino EtherShield / Ethernet Arduino either come with PoE module soldered in, or You may buy one and solder in yourself later. The cost of including it is left up to you.
What would the cost be to allow for such an optional on board module?
Would there be space to place it?
Could the same PoE module used with the arduinos be used for the (imaginary future) RPi?

Re: POE support on Rpi 3

Posted: Mon Mar 16, 2015 11:57 pm
by W. H. Heydt
It occurs to me that one item that could go on a wish list that *hasn't* been mentioned yet is audio input. Mind you, I don't have a need for it, but I'm sure there are a fair number of people that could find uses for it.

On those elements on my own wish list... Right now when I run ConReg at DunDraCon, I use 5 Pis as input terminals with 2 Cubieboards running the database (replicated) stored on SSDs, and an Odroid-C1 acting as an NTP server. Even if no other changes to the specs, if a "Pi2B+" showed up with a SATA port, I would switch to that to handle the work being done on the Cubieboards. If a "Pi2B+" showed up with an RTC, I'd ditch the Odroid-C1. If such a "Pi2B+" had both a SATA port and an RTC, I'd use them and get rid of both the Cubieboards and the Odriod-C1

Now I will agree that my use case is not common...certainly not common enough to drive the design choices of the RPF, but that's situation I have.