jamesh
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Re: PoE HAT - USB Ports not working - over-current

Wed Oct 03, 2018 9:13 am

techrep wrote:
Tue Oct 02, 2018 10:28 pm
This sounds like your microSD card has old bootcode on it that doesn't support the 3B+ The lightning bolt low-power warning is a classic symptom on this. Make sure you have a fully up to date Raspbian Stretch image on your card.
Put the latest version on SD and booted. I get past the rainbow cube but still get the lightning bolt. I took it to the bench and lashed up a programmable power supply to a random USB cable I had sitting around. In addition I have a Dell USB keyboard & mouse that is tied to the Pi using Dell's universal USB receiver. I imagine that puts more than a few milliamps of load on the Pi's USB supply.

I power up the Pi and monitor the boot sequence using an external HDMI monitor. If I set the external power supply to 4.9 volts and start the process I'll see an overcurrent message in the boot messages that fly by. If I increment the power supply voltage by .1 (100mV) and observe the same sequence I will see a clean boot sequence in the messages at 5.0v but will still see seemingly random flashes of the lightning bolt.

What I have done is exercised the Pi in various configurations and I don't see the lightning bolt go away until approximately 5.3v is applied. I've monitored the output of the supply both at the binding posts and at the Pi proper (test points ground, pins 3,4,5&6 and pin 7 after the polyfuse) and the reading are within a few 10's of millivolts. I chalk this up to the voltage drop presented by the super thin power wires in the junked USB cable I am using.

Long story short is that unless the PoE hat is going to have a very stiff supply with a small handful of overhead voltage we can expect to see this continue.

I'm more than happy to help troubleshoot the issue if somebody is willing to craft a test regime for me to follow.

Alternatively I can send off the kit to JamesH and team as both parts are functionally useless to me in its current state. I say this in a non-pejorative way, sending them back does nothing to further the troubleshooting and only puts a minimal amount of cash back into my pocket.

Please let me know if I can contribute in some way.

-Chris
Can you contact me via [email protected] please, FAO James Hughes. Thanks.
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techrep
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Re: PoE HAT - USB Ports not working - over-current

Wed Oct 03, 2018 4:25 pm

James,

Didn't see this until I got to work this morning (yes, I admit it, I was watching TV yesterday...) and saw your request. Sent you email from my home account. More than happy to help, just let me know what you need.

I'm sure your team will get to the bottom of this in short order.

-Chris

jamesh
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Re: PoE HAT - USB Ports not working - over-current

Thu Oct 04, 2018 8:59 am

Thanks for everyone who have been in contact.

We no longer need any more for in house for testing, so if you are having problem with your PoE HAT, please return it to your retailer for a refund. All retailers are aware of the issue, there should be no problems with getting a refund.
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Roken
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Re: PoE HAT - USB Ports not working - over-current

Thu Oct 04, 2018 6:36 pm

I assume if we are running the Pi without any USB devices connected, there's no harm in keeping it?

For the others, I picked up some PoE splitters which are working OK.
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Re: PoE HAT - USB Ports not working - over-current

Thu Oct 04, 2018 6:48 pm

Roken wrote: I assume if we are running the Pi without any USB devices connected, there's no harm in keeping it?
The only harm I can think of is that if it resets anyway (as some people have reported), it would spam your logs.

Roken
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Re: PoE HAT - USB Ports not working - over-current

Thu Oct 04, 2018 6:50 pm

I have rootfs on an 1TB NFS drive, too, so I can manually clean the logs periodically with no real problem.
Headless PI. OMG, someone cut it's head off. Oh, hang on. it didn't have one to start with.

kawakawa
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Re: PoE HAT - USB Ports not working - over-current

Thu Oct 04, 2018 11:30 pm

Hello,

is there a way to "repair" the PoE-HATs? A way how to modify them, so thay would not must be returned?

Maybe larger capacitors on the HAT, which will stabilize the voltage?

If the Raspberry engineers would support instructions how to do this, many owners would repair their PoE HATs by themselfes.

Regards
Artur

The_Raven
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Re: PoE HAT - USB Ports not working - over-current

Fri Oct 05, 2018 9:10 am

If it "spams" the log and the log is on a SD it reduces the life of the SD dramatically. Not a good idea ;)

I discovered that some part on the Hat running hot. Hope this does not reduce the life time. Ok it was measured away from the Pi and because of that without fan. Attached to the pi and with running fan it should be cooler.
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weust
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Re: PoE HAT - USB Ports not working - over-current

Sat Oct 06, 2018 12:04 pm

kawakawa wrote:
Thu Oct 04, 2018 11:30 pm
Hello,

is there a way to "repair" the PoE-HATs? A way how to modify them, so thay would not must be returned?

Maybe larger capacitors on the HAT, which will stabilize the voltage?

If the Raspberry engineers would support instructions how to do this, many owners would repair their PoE HATs by themselfes.

Regards
Artur
Try reading the topic and it's replies by the engineers.

the_ewan
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Re: PoE HAT - USB Ports not working - over-current

Sat Oct 06, 2018 9:12 pm

weust wrote:
Sat Oct 06, 2018 12:04 pm
Try reading the topic and it's replies by the engineers.
You mean like the ones from a few weeks back promising a blog post with the potential DIY fixes 'soon'? Because as far as I can see the only post about the PoE Hat on the blog is the launch announcement (which hasn't been updated), and the nearest thing to a guide for would-be DIY fixers is the the El Reg article.

It's not unreasonable that people would be asking about the instructions.

jamesh
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Re: PoE HAT - USB Ports not working - over-current

Sun Oct 07, 2018 8:02 am

Blog is in planning. We want to ensure we get things right this time, so are not hurrying.

If the Hat works ok for you, use it, if not I would suggest returning it
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the_ewan
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Re: PoE HAT - USB Ports not working - over-current

Sun Oct 07, 2018 4:13 pm

I can appreciate not wanting to say anything misleading, but IMO you could really do with some sort of stop-gap status update, even if only an update to the existing launch announcement post.

At the moment the most up to date easy to find statements in the Foundation's official looking channels (i.e. not this discussion) are that that the PoE hat is available now and everything's great. Leaving that uncorrected is also kinda misleading.

I only found this thread after since googling to find out why everyone was mysteriously out of stock of the hats. I got the message in the end, but it was a lot less obvious than a blog just saying "The PoE hats aren't on sale at the moment due to a problem, see this forum thread for what we know so far, more news when we have it".

jamesh
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Re: PoE HAT - USB Ports not working - over-current

Mon Oct 08, 2018 4:09 pm

I'll see what we can do about an update.
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The_Raven
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Re: PoE HAT - USB Ports not working - over-current

Mon Oct 08, 2018 6:16 pm

ATM i am testing my solution with 2 caps and a coil.
So far it works well.

jamesh
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Re: PoE HAT - USB Ports not working - over-current

Tue Oct 09, 2018 12:58 pm

Spoke to people, we are hopeful to have a blog post with gory details out soon. Content needs to be confirmed by the big boss. Which reminds me to email the big boss.
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the_ewan
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Re: PoE HAT - USB Ports not working - over-current

Tue Oct 09, 2018 1:11 pm

Nice; I think that will help.

So far it hasn't been really obvious that there's 'a thing' going on at all; it wouldn't exactly be unprecedented for a newly released Foundation product to actually just sell out of stock through simple popularity; it took me a while between firstheading over to Pimoroni to pick one up and then realising that there was more to it this time.

Anything that helps raise the profile of this will be useful.

An ETA on version two would be really useful ;)

jamesh
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Re: PoE HAT - USB Ports not working - over-current

Tue Oct 09, 2018 1:13 pm

the_ewan wrote:
Tue Oct 09, 2018 1:11 pm
Nice; I think that will help.

So far it hasn't been really obvious that there's 'a thing' going on at all; it wouldn't exactly be unprecedented for a newly released Foundation product to actually just sell out of stock through simple popularity; it took me a while between firstheading over to Pimoroni to pick one up and then realising that there was more to it this time.

Anything that helps raise the profile of this will be useful.

An ETA on version two would be really useful ;)
Interesting - I hadn't realised that people didn't know there was a problem.

There will be a v2, blog post should cover all the details.
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the_ewan
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Re: PoE HAT - USB Ports not working - over-current

Tue Oct 09, 2018 1:30 pm

Interesting - I hadn't realised that people didn't know there as a problem.
I might be in a slightly unusual situation because I'd not been following this all that closely - I remember the original announcement, didn't have PoE switches at the time, have since got some for other kit, then thought "A ha, I shall get one of those nifty PoE hats I remember hearing about", then found I couldn't. Then there was some Googling, the El Reg piece, then this forum thread.

I had looked at the blog to see if there was any news of sellouts and more availability (there was, IIRC, pretty much a running commentary when the Pi Zero first launched and sold out everywhere), and there wasn't any sign of anything, which is why I'm quite keen on there being something to catch anyone else who follows the same sort of path, even if you hadn't been ready to post all the gory details.

Clearly, anyone who's got one of the first batch and had it not work for them knows they've got a problem, but for those of us who don't have one at all it just looks for all the world as though it should be available, but has mysteriously vanished.

Anyway, I shall look forward to the blog post, then hopefully a v2 in the not too distant future.

Roken
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Re: PoE HAT - USB Ports not working - over-current

Tue Oct 09, 2018 8:50 pm

Not everyone who got one finds it useless. On a headless, no peripherals system, it's still just peachy.
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Re: PoE HAT - USB Ports not working - over-current

Wed Oct 10, 2018 8:46 am

Roken wrote:
Tue Oct 09, 2018 8:50 pm
Not everyone who got one finds it useless. On a headless, no peripherals system, it's still just peachy.
Exactly. I believe it may also depend on the device providing the PoE power.
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Re: PoE HAT - USB Ports not working - over-current

Wed Oct 10, 2018 1:01 pm

With regard to the blog post, there are some ducks that need to be got in line before we post an update, not sure how long that will take, but fairly soon, probably sometime next week. We've got a lot of work done * on the problem, and need to ensure that everything is now OK.


* And thanks to those people who have supplied boards showing the problem to us, and for those who have been testing for us.
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weust
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Re: PoE HAT - USB Ports not working - over-current

Wed Oct 10, 2018 2:43 pm

Roken wrote:
Tue Oct 09, 2018 8:50 pm
Not everyone who got one finds it useless. On a headless, no peripherals system, it's still just peachy.
In my case I run it using LibreELEC without any USB devices.
Started getting more and more yellow lightning bolt icons and at some point it just crashed.
Using the power adapter atm and no issue.

So for me, headless and no peripherals it's not peachy at all.

POE wise I use a Ubiquiti 24 port 250W switch. Just a few low power devices, nothing special.
Works great with splitters (once you set the port to 100FDX).

jamesh
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Re: PoE HAT - USB Ports not working - over-current

Wed Oct 10, 2018 3:10 pm

weust wrote:
Wed Oct 10, 2018 2:43 pm
Roken wrote:
Tue Oct 09, 2018 8:50 pm
Not everyone who got one finds it useless. On a headless, no peripherals system, it's still just peachy.
In my case I run it using LibreELEC without any USB devices.
Started getting more and more yellow lightning bolt icons and at some point it just crashed.
Using the power adapter atm and no issue.

So for me, headless and no peripherals it's not peachy at all.

POE wise I use a Ubiquiti 24 port 250W switch. Just a few low power devices, nothing special.
Works great with splitters (once you set the port to 100FDX).
It does depend on a number of circumstances.

I'd suggest returning it.
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Re: PoE HAT - USB Ports not working - over-current

Thu Oct 11, 2018 6:06 am

I initially tested both of my PoE hats with a USB hard drive with two USB connectors for adequate power and didn't have any issues.

Today I brought one into work and tried to power it over PoE and had it actually throw over-current errors with just a keyboard and mouse in the two ports beside the NIC. I had to plug it into a power adapter to be able to even use the keyboard.

When my co-worker suggested swapping it to another cable we had to another wall port, things worked perfectly.

Very odd.
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weust
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Re: PoE HAT - USB Ports not working - over-current

Thu Oct 11, 2018 8:49 am

jamesh wrote:
Wed Oct 10, 2018 3:10 pm
weust wrote:
Wed Oct 10, 2018 2:43 pm
Roken wrote:
Tue Oct 09, 2018 8:50 pm
Not everyone who got one finds it useless. On a headless, no peripherals system, it's still just peachy.
In my case I run it using LibreELEC without any USB devices.
Started getting more and more yellow lightning bolt icons and at some point it just crashed.
Using the power adapter atm and no issue.

So for me, headless and no peripherals it's not peachy at all.

POE wise I use a Ubiquiti 24 port 250W switch. Just a few low power devices, nothing special.
Works great with splitters (once you set the port to 100FDX).
It does depend on a number of circumstances.

I'd suggest returning it.
I bought at The Pi Hut before it was for sale here in The Netherlands.
Sending it back is probably more expensive then keeping it and doing a manual modification (if that turns out to be a thing to do, depending on your (the engineers) findings.

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