damianoloan
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Re: No power to keyboard

Tue Jul 24, 2012 11:34 am

Hi,

If anyone has any suggestions to the issues I described above, I'd be very grateful.

In China, Element14 say replacements will take 4-5 months, even after several emails. I just want to get started as quickly as possible, whether by returning the product or otherwise, but so far it seems that events are conspiring against me.

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spadge_2356
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Re: No power to keyboard

Wed Jul 25, 2012 8:57 am

El_Presidente wrote:Maybe he can post details of the hub and PS when he gets it, as well as the obvious pass/fail. :)
I made a school boy error on this one, I impulsively bought it without looking at the specs for the PSU. In fact on the listing it doesn't give the specs for it. Will let everyone know if it works of course (fingers crossed).
I'm still a Linux amateur, though I've been tinkering for the last 3 years. I use these forums for help, Please be patient if I ask a 'stupid' question. we all start with learning the basics first. Thank You :-)

El_Presidente
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Location: Bolton, UK

Re: No power to keyboard

Wed Jul 25, 2012 10:47 am

damianoloan wrote:If anyone has any suggestions to the issues I described above, I'd be very grateful.
Wish I could offer more constructive advice than this, but here goes:-

First, try a different distro, Raspian Wheezy is the latest and most regard as the best (most stable?).

Check your main power supply to the Pi - ensure it gives you as close to 5.0v at TP1/TP2 as possible (say 4.9v), this helps generally with USB power too. It needs to be rated minimum 700ma.

Connecting any hub, try to get a decent quality one with a solid 5v power supply - something like 2amps. Avoid cheap and nasty low rated hub adapters.

Have as many alternative USB devices as possible to test if you have trouble. Put your hub on one Pi USB port and a wired basic keyboard on the second Pi USB. Put your mouse (initially just that) on your powered hub. Start LXDE & try everything, swap out to alternative hub/ps/kb/mouse if you have them, until you have stability and (importantly) working network.

Only move on with more USB devices after the above is stable.

The USB subsystem has issues, partly because of the use of polyfuses, but also likely bugs in kernel/USB drivers (especially with any USB v1/1.1 devices). This is being worked on by some smart people and may well improve in the coming weeks/months.

If you are having no luck and facing a nightmare return then consider a small mod to your Pi board - to add 1 ohm resistors across each USB polyfuse (R1/R2). This removes them and stops significant voltage drop and current restriction on the built-in ports. It can help with direct use of wireless dongles etc. You may need to look again at your main power adapter if you do this - perhaps up it's capacity a little.
Start reading this thread from around this point if you want more about the mod:
http://www.raspberrypi.org/phpBB3/viewt ... 88#p121188

Best of luck!
-----------------------------------------------------------------------------------------
Never trust a man, who when left alone with a tea cosey, doesn't try it on.

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spadge_2356
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Re: No power to keyboard

Wed Jul 25, 2012 3:42 pm

Thanks El_Presidente sounds like some excellent advice. I'm going to try the USB hub approach first and post back when I get some results as I still need some practice with my soldering skills (not the steadiest hand!).

Love the signature btw, what sort of man DOESN'T put a tea cosy on their head? :D
I'm still a Linux amateur, though I've been tinkering for the last 3 years. I use these forums for help, Please be patient if I ask a 'stupid' question. we all start with learning the basics first. Thank You :-)

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spadge_2356
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Re: No power to keyboard

Fri Aug 24, 2012 6:31 pm

Hi All,

It's been a while since I wrote in this thread however I finally got round to testing the powered USB hub I bought from ebay.

The first thing I noticed was that the hub will power the raspberry pi without the original micro usb 5v 1A power supply but the keyboard and mouse will not work unless you plug in the micro usb AND the powered usb hub together. As soon as I plugged in both together the optical mouse lit up and the keyboard now types.

I have finally been able to reach the GUI of the raspi since I purchased it a few months ago! However I have noticed that the mouse can sometimes be tempremental (moving straight to the task bar at the bottom and refuses to move for 2 or 3 minutes).

I have a new problem now, I am trying to use Midori to access the internet but it keeps throwing up 'page not found' error. I have made sure the ethernet cable is connected etc, can anyone suggest where I am going wrong? Still not having alot of luck :-(
I'm still a Linux amateur, though I've been tinkering for the last 3 years. I use these forums for help, Please be patient if I ask a 'stupid' question. we all start with learning the basics first. Thank You :-)

obcd
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Re: No power to keyboard

Fri Aug 24, 2012 8:11 pm

run ifconfig and see if you have an ip for eth0. (Assuming your Pi is connected wired and you use dhcp to obtain an ip adress)
try to ping your router or another pc on your network and see if it gives you a response.
Describe the condition of the leds on your Pi. 2 or 3 of them are related to your network connection.

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spadge_2356
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Re: No power to keyboard

Wed Oct 10, 2012 2:38 pm

El_Presidente wrote: Maybe he can post details of the hub and PS when he gets it, as well as the obvious pass/fail. :)
Sorry forgot to mention, the power supply with the USB hub was a 5v 1A.

On a separate note I'm having a punt at getting raspbmc working. So, now I'm binning off both power supplies in favour of a newly aquired 5v 3A supply to make sure everything has enough power.
I'm still a Linux amateur, though I've been tinkering for the last 3 years. I use these forums for help, Please be patient if I ask a 'stupid' question. we all start with learning the basics first. Thank You :-)

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RaTTuS
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Re: No power to keyboard

Wed Oct 10, 2012 2:43 pm

power the RPi from the hub [using the micro usb socket] and use that hub also for the periphals
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simon4
Posts: 4
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Re: No power to keyboard

Wed Oct 10, 2012 9:46 pm

I'm having the exact same problem.

- Flashed the latest raspbmc to SD card
- Ran initial setup and booted into XBMC, everything seems to work but the keyboard it not detected, not even the num-lock or caps-lock LED lights up.

I'm using...
- Logitech K120 keyboard (its on the list of verified perihperials): No USB hub, no backlight keys, nothing. This is as basic as it gets. The back of the keyboard indicates a 100 mA rating.
- 1.2A power supply from RS electronics (http://raspberrypi.rsdelivers.com/produ ... 63053.aspx)

I currently have no access to a powered USB hub. Is it, under my circumstances, still likely that the PSU is too weak (and why would RS sell a PSU explicitly for the RPi when it can't even power the most basic keyboard?!)?

Edit: I'm actually able to charge my phone by connecting it via micro USB cable to one of the RPi USB ports.

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spadge_2356
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Re: No power to keyboard

Thu Oct 11, 2012 7:05 am

simon4 wrote:I'm having the exact same problem.

- Flashed the latest raspbmc to SD card
- Ran initial setup and booted into XBMC, everything seems to work but the keyboard it not detected, not even the num-lock or caps-lock LED lights up.

I'm using...
- Logitech K120 keyboard (its on the list of verified perihperials): No USB hub, no backlight keys, nothing. This is as basic as it gets. The back of the keyboard indicates a 100 mA rating.
- 1.2A power supply from RS electronics (http://raspberrypi.rsdelivers.com/produ ... 63053.aspx)

I currently have no access to a powered USB hub. Is it, under my circumstances, still likely that the PSU is too weak (and why would RS sell a PSU explicitly for the RPi when it can't even power the most basic keyboard?!)?

Edit: I'm actually able to charge my phone by connecting it via micro USB cable to one of the RPi USB ports.
Well I've done alot of reading since I last posted and learned ALOT too! I would argue that a USB hub is essential prerequisite! I was using a 5v 1A PSU with the Pi and a separate 5v 1A PSU for the USB hub.

The answer for me was to get a bigger PSU, I ordered a 5v 3A PSU from ebay, threw away the other two, used the 3A supply to power the USB hub, and connected the micro usb port on the Pi to the hub.

Now all my keyboard issues are gone, the Pi doesn't freeze, or any of the other problems I've had before I got the better PSU. XBMC works better on my Pi (flawless actually) than my Ubuntu 11.10 machine.

So in summary get a powered USB hub with a 5v supply (exactly 5v otherwise you'll snuff it) and enough current to power all the peripherals (3A was sufficient for me but I guess you could go higher if you wanted to add more things) including the hub and the Pi
I'm still a Linux amateur, though I've been tinkering for the last 3 years. I use these forums for help, Please be patient if I ask a 'stupid' question. we all start with learning the basics first. Thank You :-)

simon4
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Re: No power to keyboard

Thu Oct 11, 2012 8:23 am

I refuse using a powered USB hub with the RPi. What's the point in buying a mini computer and then having to attach a powered USB hub to it that's at least the size of the computer itself? Not to mention it probably costs as much too.

My keyboard is on the list of verified peripherials, so it shouldn't be a problem for a RPi USB port to support the necessary 100 mA. From my point of view, there are three possible causes for the problem.

- The keyboard draws more than the 100 mA specified
- The PSU is too weak (highly unlikely)
- The RPi is broken (I read something about bad solder joints?)

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RaTTuS
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Re: No power to keyboard

Thu Oct 11, 2012 8:41 am

simon4 wrote:I refuse using a powered USB hub with the RPi. What's the point in buying a mini computer and then having to attach a powered USB hub to it that's at least the size of the computer itself? Not to mention it probably costs as much too.

My keyboard is on the list of verified peripherials, so it shouldn't be a problem for a RPi USB port to support the necessary 100 mA. From my point of view, there are three possible causes for the problem.

- The keyboard draws more than the 100 mA specified
- The PSU is too weak (highly unlikely)
- The RPi is broken (I read something about bad solder joints?)
refuse all you want - it's up to you.
what revision of the RPi do you have?
I've noticed that any keyboard with lights [even caps lock ] are very iffy with a poor PSU
can you ssh in? if so you should be able to see what happens when you plug in the keybaord [ tail -f /var/log/syslog]
ignore the RPI may be broken - you will ahve to be very unlucky to get one that is
have you tried other keyboards , both slots ? etc
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simon4
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Re: No power to keyboard

Thu Oct 11, 2012 9:27 am

I'm aware of that :) It might sound stubborn, but I just can't believe that I'm not able to use the simplest of keyboards with my RPi without using an external USB hub. Especially as I'm using a verified keyboard and a good quality 1.2A PSU that conforms with the official RPi specs:
Model B owners using networking and high-current USB peripherals will require a supply which can source 700mA (many phone chargers meet this requirement). Model A owners with powered USB devices will be able to get away with a much lower current capacity (300mA feels like a reasonable safety margin).
Note that it says 700 mA for high-current USB peripherials! I have tried both USB ports. I can charge my phone on both USB ports.

I will try a different keyboard as soon as I can. I will also try a different PSU and SSH'ing intp the RPi to see whats going on. Thanks.

simon4
Posts: 4
Joined: Wed Oct 10, 2012 9:37 pm

Re: No power to keyboard

Fri Oct 12, 2012 8:50 am

I solved the problem by SSH'ing into the RPi and setting the keyboard layout and timezone. From the Raspbmc FAQ:
Q: How do I change my keyboard layout or timezone?

A: Raspbmc will prompt you to do so the first time that you login via SSH
After that, the keyboard was usable.

drgeoff
Posts: 9806
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Re: No power to keyboard

Fri Oct 12, 2012 6:18 pm

simon4 wrote:I solved the problem by SSH'ing into the RPi and setting the keyboard layout and timezone. From the Raspbmc FAQ:
Q: How do I change my keyboard layout or timezone?

A: Raspbmc will prompt you to do so the first time that you login via SSH
After that, the keyboard was usable.
I very much doubt that changing the keyboard layout and timezone is what really made your previously non-working keyboard usable. But if it remains operational .....

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