Anyone know how to monitor power used on USB Port?

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Level 1

46 points

Anyone know how to monitor power used on USB Port?

I have an external quickertek usb wireless device that keeps shutting down my Macbook pro. It runs fine for a few days and then locks the entire system up. Quicktek made me a special device with an external power adapter thinking the problem was the USB port being asked for more power than it could deliver but the system is still crashing. I'd like to monitor my power output on that single USB port to see if the new device is really working properly but not sure how to measure power consumption on a usb.

Can anyone tell me if this is possible and if so how?

Thanks,

glenn

MBP, Mac OS X (10.5)

Posted on May 19, 2009 8:10 AM

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Answer 1

May 19, 2009 8:33 AM in response to cybercrypt13

There is a USB monitoring tool in the Apple Developer Tools package. You can register as an Apple developer, then download and install the tools. Once that is done you can run the USB monitor to see what's happening on the USB busses.

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Answer 2

nerowolfe

Level 6

13,090 points

May 19, 2009 9:53 AM in response to Mabel O'Farrell

Mabel O'Farrell wrote:
There is a USB monitoring tool in the Apple Developer Tools package. You can register as an Apple developer, then download and install the tools. Once that is done you can run the USB monitor to see what's happening on the USB busses.

Good call -
It's named
USB Prober.app

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Answer 3

cybercrypt13 Author

Level 1

46 points

May 19, 2009 11:28 AM in response to nerowolfe

thanks guys, I'm not sure how accurate the actual current power being used is as it seems to always say 500ma but I'll play around with it and see if I can get it to work for me.

glenn

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Answer 4

nerowolfe

Level 6

13,090 points

May 19, 2009 11:43 AM in response to cybercrypt13

cybercrypt13 wrote:
thanks guys, I'm not sure how accurate the actual current power being used is as it seems to always say 500ma but I'll play around with it and see if I can get it to work for me.

glenn

Remember that 500 ma is the limit, so if a device attempts to draw more, it most likely will be current-limited at .5A.
At least it's a start.
This might also be useful:
http://developer.apple.com/documentation/HardwareDrivers/Conceptual/HWTechUSB/Articles/usbimplementation.html

And thanks 🙂

Message was edited by: nerowolfe

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