kalehrl
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Re: The Raspberry Pi Model B+ Q&A thread

Tue Dec 09, 2014 8:54 pm

As far as I understand, both USB and ethernet ports share the same bus (or something like that) which caused ethernet to drop occasionally. I know it invariably did in my case so I wonder if B+ now has the separate buses for ethernet and USB?

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Re: The Raspberry Pi Model B+ Q&A thread

Tue Dec 09, 2014 9:05 pm

kalehrl wrote:As far as I understand, both USB and ethernet ports share the same bus (or something like that) which caused ethernet to drop occasionally. I know it invariably did in my case so I wonder if B+ now has the separate buses for ethernet and USB?
System is the same, just a slightly different chip that supports 4 USB ports.
BTW: I have never experienced any ethernet problems with B rev 1, rev 2 (256 & 512MB) and B+
And a lot of work has been done to get any USB problems solved.

Gr.
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Re: The Raspberry Pi Model B+ Q&A thread

Tue Dec 09, 2014 9:19 pm

kalehrl wrote:As far as I understand, both USB and ethernet ports share the same bus (or something like that) which caused ethernet to drop occasionally. I know it invariably did in my case so I wonder if B+ now has the separate buses for ethernet and USB?
Nope, that's a giant leap of logic. They're two separate observations. If that statement was true, then everybody would experience it.

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Re: The Raspberry Pi Model B+ Q&A thread

Tue Dec 09, 2014 9:20 pm

With the Model B, if you had a dodgy power supply then the Ethernet connection could drop out before other USB devices did because the internal regulators on the LAN9512 could brown out before low-voltage tolerant devices attached to USB noticed.

With the B+, the headroom is much improved. If you ignored the VBus constraint and assumed that USB peripherals would work whatever the voltage, the B+ can operate with input voltages as low as 3.5V.
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kalehrl
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Re: The Raspberry Pi Model B+ Q&A thread

Wed Dec 10, 2014 11:31 am

The power supply was 1.2A from RS Components so it can't have been dodgy.
I guess I won't risk it the second time since not much has changes in the latest model.

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Re: The Raspberry Pi Model B+ Q&A thread

Wed Dec 10, 2014 12:18 pm

kalehrl wrote:The power supply was 1.2A from RS Components so it can't have been dodgy.
I guess I won't risk it the second time since not much has changes in the latest model.
Duh! You have been told what the problem was, almost certainly power, but I suspect caused by a dodgy USB cable, not the power supply. I had exactly the same symptoms from a solid desktop power supply - a bad cable. This is nothing to do with the design of the ethernet.

The current model (and the older one TBH) work FINE. People have been running them for months non-stop with no problem. The B+ power supply is better, so even with a bad cable is likely to work better anyway.

Let me reiterate - the problem was NOT the design, but something else. So the design is NOT a reason to reject the Raspi.
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kalehrl
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Re: The Raspberry Pi Model B+ Q&A thread

Wed Dec 10, 2014 6:11 pm

RS Components is a reputable company which advertises this power supply as an accessory to raspi. I can't imagine them selling it without properly testing it. The cable was fixed to the power adapter, it couldn't be changed. And I'm not the only one to complain about ethernet on this forum. There are many threads where people ask for ethernet watchdog scripts. If etherent was really that reliable, why ask for a watchdog to monitor it and reboot raspi if ethernet is dropped.

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Re: The Raspberry Pi Model B+ Q&A thread

Wed Dec 10, 2014 6:15 pm

And I'm not the only one to complain about ethernet on this forum. There are many threads where people ask for ethernet watchdog scripts. If etherent was really that reliable, why ask for a watchdog to monitor it and reboot raspi if ethernet is dropped.
Is that so? The only ones I can remember seeing were about wifi dongles, not the ethernet port...

Gr.
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Re: The Raspberry Pi Model B+ Q&A thread

Wed Dec 10, 2014 7:35 pm

I have six RPi's model B's. One with 256 MB ram. Two of them drop ethernet irregularly. It can take a week, even a month. Sometimes it's after 20 minutes.

I must have tried every patch and experimental fix that was talked about on this forum. It changes, but it doesn't resolve the problem completely and indefinitely.

I think it's not the hardware since some revisions of Raspbian don't seem to have the problem. But I don't want to run an old system since these should be connected to the internet.

It's not a PSU problem, since all the PSU's work well with the other Pi's. And even on a Farnell lab supply they behave more or less the same.

For the time being, I use the other four that work.

And it's the same for audio over USB. It works at 16 bit/44.1 KHz, usually. Go to a higher sample rate or 24 bits and you'll get dropouts from time to time. I can see no logic behind it. I've tested every interface I could get to work with raspbian. It's certainly not interface related, since all of these work with Windows and OSX. The behaviour is even different for different Rpi's (with the same SD card). At least, with audio over USB, they all have problems. Doing more than 2 channels seems impossible.

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Re: The Raspberry Pi Model B+ Q&A thread

Wed Dec 10, 2014 7:46 pm

And that's not the only problem with raspi.
It took a long time before I could use my Microsoft Wireless Comfort Keyboard 5000.
It kept repeating or missing keys that I couldn't even log in typing password.
I could use it by adding something to boot line which would then force all USBs to be 1.0.
Only after a year or so the fix became a part of official firmware.
I guess something was wrong with my keyboard, not raspi. :D
Not to mention SD card corruption after some time.

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Re: The Raspberry Pi Model B+ Q&A thread

Wed Dec 10, 2014 9:58 pm

cyrano wrote: I must have tried every patch and experimental fix that was talked about on this forum. It changes, but it doesn't resolve the problem completely and indefinitely.
*Every* experimental fix? When I was having the drop problem a couple of years ago, I found and modified a shell script that checks the connection every five minutes (cron job) and restarts the connection if it's down. I haven't had to deal with the issue since. I know data on it got posted.

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Re: The Raspberry Pi Model B+ Q&A thread

Wed Dec 10, 2014 11:02 pm

kalehrl wrote:And that's not the only problem with raspi.
It took a long time before I could use my Microsoft Wireless Comfort Keyboard 5000.
It kept repeating or missing keys that I couldn't even log in typing password.
I could use it by adding something to boot line which would then force all USBs to be 1.0.
Only after a year or so the fix became a part of official firmware.
I guess something was wrong with my keyboard, not raspi. :D
Not to mention SD card corruption after some time.
Yawn. Known problem, fixed a year ago. Nothing wrong with your keyboard, but with the Synopsys USB hardware in the chip. Since circumvented (for the majority of use cases) with some deft coding by the Foundation.

I'd suggest giving up with the Raspi. Clearly a SBC for $35 isn't what you need, there are plenty of more expensive alternatives with a different bug list you can try,
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cyrano
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Re: The Raspberry Pi Model B+ Q&A thread

Wed Dec 10, 2014 11:22 pm

Every one that I encountered. I might have missed some, but for some stuff you still need to revert to USB 1.1. Which is fine for audio. But not for ethernet. One would think that that might get fixed eventually...

It is also possible that I have two pi's with a defect. Two out of six isn't really good is it? I could have returned the Pi's for a warranty replacement, but it could cost more than simply buying another one. Dealing with the local official distributor is a PITA. I could have cheated and return them through my unofficial shop. But I don't want to bother those people with a problem created by others. Besides, the new ones might just fail too.

I won't hold Wifi problems against the Pi. Wifi sticks are notoriously difficult because you're never certain what hardware is in them and Linux doesn't have a lot of drivers. You won't hear me whine about that.

I haven't had any problems myself with corruption of SD cards. Maybe because all my SD cards came with camera's and those manufacturers don't buy fakes? But you won't hear me denying that there is a problem with corruption.

But the ethernet is on board and should work. Denying that there are problems isn't a good way to deal with it. There are ethernet problems for some of the users. "It seems to work for others" is just a bad answer.

I won't blame people. They can't help it. They had to live through loosing their jobs and they remained motivated. They kept investing their own time. Maybe the foundation could step in and hire some of them to do paid development?

It seems to be a general problem with charities. The work that has been done, was great. There is no doubt about that. And trying to stimulate education is a noble goal. It's also a goal that might fire back if some problems don't get fixed. After all, you wouldn't want to hand education a partly broken tool, would you?

I'm a member of a couple of groups that you could call maker spaces, or even hacker spaces. The question I heard most about the Pi in the beginning was "Where can I get one?" Lately, that question is turning in "Is it useful or is it a hype?" If you ask why, you often get remarks about card corruption, incomplete distro's and, yes, unreliable or slow ethernet. For instance, a lot of people were excited about running Kali on the Pi. Most of those who tried, have bought something else, mostly because of ethernet, or performance.

And it is strange, because the two Pi's that I have with a problem, seem to behave well when running Kali.

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Re: The Raspberry Pi Model B+ Q&A thread

Thu Dec 11, 2014 8:59 am

I really don't like the previous post. Full of concerns that are simply not there. I'd regard it as concern trolling, the act of subtly introducing doubts in to people minds in order to discredit, despite there being little or no evidence that the doubts are valid. So, to the poster, please desist. If you do have specific issue that you think need addresses, post a question. But putting in a bunch of unprovable and probably incorrect 'facts' in to a post is just plain trolling.

There is an implication that there is a ethernet problem. As far as the Foundation knows, there ISN'T one. Some people claim problems, but AFAIK, the Foundation has never been able to replicate ANY ethernet problems whatsoever - and they do have access to a lot of boards. SO, if you have one that seems erratic, it might be worth posting a new thread, and possible getting the board to the Foundation for testing. First of course, make sure the power supply is decent and you have up to date software. and It worth noting that there are 4M Raspbery Pi;'s out there, and the number of complaints about ethernet are infinitesimal in comparison. That sort of statistic usually means the HW design is fine, there is an issue elsewhere. Power is the usual suspect.

SD card corruption. AFAIK, there was a problem with some SS cards which has been fixed. I suspect that the majority of remaining corruption issues are down to bad power down processes. However, there may still be a bug somewhere in the SD card handling, but it is extremely rare and probably card specific.

Incomplete distro? Er, what? Kali Linux? Why? These are not Pi specific problems, so are a strawman argument.

As for your comment on charities, how rude, and so so wrong. The Foundation has a team of 8 software engineers working full time, in NO WAY AT ALL have they stopped working on the device or the accompanying software. This isn't a build and dump exercise like so many of the other SBC's, this is a long term commitment to education. So your statement is false, wrong, bad, and just plain mean.

And to stop this thread degenerating in to name calling and more incorrect statements, it stops here.
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