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[ 5 posts ] |
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Carambola USB power issue?
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pippo
Joined: 12 Jan 2012, 00:20
Posts: 13
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Hi,
When i attach a USB device to the USB port it seems that is powered only for a second. I can see it because the power led flashes only once...
I installed the basics usb kernel modules .
lsusb only listes the USB internal hub.
dmesg shows nothing.
Could it be a power issue on the dev-board? How can i test it?
I'm powering carambola with a 12v, 2000mA stabilized power supply.
Thanks for the help!!
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| 18 Jan 2012, 13:25 |
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pippo
Joined: 12 Jan 2012, 00:20
Posts: 13
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Well, i connected a voltmeter to usb pins and i have 5 V.
Infact if i connect an old apple mighty mouse the led inside the mouse turns on but nothing on dmesg and nothing on lsusb.
If i connect another usb mouse wich "consume" 100 mA the led inside the mouse is off.
Now i have two "theories":
1) usb port is low on current (i really don't know how to test it)
2) there is somenthing wrong on hotplug configuration
Am i missing something? Can you help me?
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| 22 Jan 2012, 09:15 |
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gedass
Joined: 07 Dec 2011, 16:01
Posts: 525
Location: Lithuania
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| 22 Jan 2012, 10:08 |
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pippo
Joined: 12 Jan 2012, 00:20
Posts: 13
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| 22 Jan 2012, 11:58 |
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pippo
Joined: 12 Jan 2012, 00:20
Posts: 13
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FINALLY I GOT IT!
It was an hardware issue on the dev-board!
Soldering a 10k resistor between jumper J1 and pin 40 solved the problem as in the picture at this link
Probably the builted in 10k resistor on the devboard was damaged!!!!!!
are the board tested before purchase??
Am I the only unlucky guy that had this issue?
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| 22 Jan 2012, 16:02 |
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