Dead Usb and Ethernet Ports

[jashfield730]

Hello I have a problem with my raspberry pi. I have flashed the card with the noobs OS setup but when the OS loads up I get messages like:
failed to detect eth0 and no file in /dev/event even though there is a keyboard pluged in.

I have tested the power and it is perfectly adequate 5V
Doing a quick search through the forum I found this
http://www.raspberrypi.org/phpBB3/viewt ... =28&t=5766

I tapped the X1 and it worked for one boot up.
Is there any way to fix this?

My problem is I received it as a gift at a cambridge summer school and well who would I return it for a replacement? - It is one of the google raspberry pi packs which is kind of disappointing considering some other child could have received it and just given up with the raspberry pi.

Could someone help me?
Thanks for any help given

[jashfield730]

Is there any way to fix this without having to find someone to replace the raspberry pi ?
Thanks for any help given

[mahjongg]

Does indeed seem that X1 has trouble oscillating, maybe it has had a bang that dislocated the quartz sliver. I read that sometimes re-heating (melting) the solder on the for corners of the package helps to get the crystal to start working again.

P.S. did you really measure the voltage between TP1 and TP2, during boot? failure of a crystal to start can also be caused by too low voltage, or a voltage that takes some time to raise to 5V.

[jashfield730]

Does indeed seem that X1 has trouble oscillating, maybe it has had a bang that dislocated the quartz sliver. I read that sometimes re-heating (melting) the solder on the for corners of the package helps to get the crystal to start working again.

Would I need a low wattage solder iron since the solder joints are quite small or should a 30W do fine?

[mahjongg]

30 Watt is a bit much, but would work if you do not add heat for more than a second or so.

[jashfield730]

30 Watt is a bit much, but would work if you do not add heat for more than a second or so.

I'll give it a go. Thanks for the advice

[jashfield730]

The same thing happened again it worked for one boot and then it stops working again what should I do now?
Thanks for your help

[mahjongg]

try again, heat it up a bit more.

and check TP1-TP2 voltage, should be 4.8V or more.

[jashfield730]

Ok i'll try it again, I tested the voltage between TP1 and TP2 and it was 5V in like 1 sec from I plugged the power in

[mahjongg]

The obvious solution (except returning it) could be to replace the crystal.

Another thing you might try (carefully) is to short polyfuse F3, with a bent paperclip or a crocodile clip. But be careful not to slip and short things.

If the 5V really takes 1 second to raise to 5V then that is the problem, it should need no more than a few milliseconds. But I guess you miss-measured, you need an oscilloscope to see the rise-time. I don't see how its possible for the 5V to take one second to rise, unless you have several farad of capacitance on board.

[jashfield730]

try again, heat it up a bit more.

and check TP1-TP2 voltage, should be 4.8V or more.

Well it works for more than one boot now so thats progress. I'll come back to this post if it happens again.

Thanks for all your help.

[jashfield730]

It has happened again. I'll try heating it again as before but for longer.

[jashfield730]

It has happened again. I'll try heating it again as before but for longer.

Just though I'd give you update it now works again hopefully for longer this time

[abishur]

It has happened again. I'll try heating it again as before but for longer.

Just though I'd give you update it now works again hopefully for longer this time

Were you able to check the voltage between TP1 and TP2?

[slangley]

I know this forum post is old, but I had similar issues. I turned out that the USB power cable I was using was bad. Might be a good first place to start with before mucking around soldering traces on the board.