USB device that only works if plugged into a computer?

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tchart

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#211660 5-Apr-2017 22:24

So long story but my son has a huge collection of Skylanders, figures and portals (the rfid base). The later series have figures that light up when on a portal/base (which is a USB peripheral).

Now Im attempting to use some of the figures that light up as a feature light in his room but have struck a problem.

The problem is the portal/base will only power on when its plugged into a "computer". I put that in quotes as it powers on when I use any game console, PC, raspberry pi etc USB port. Ive tried several USB wall chargers and no go. It just doesn't power on. Tried various amperage, wattage, apple, samsung chargers etc but none work.

So the question is, has anyone ever run into a USB device that will only work when plugged into a computer?

I've googled but havent struck anything yet, I assume its looking for some kind of data comms while I believe many chargers short the data pins...

richms

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#1757303 5-Apr-2017 22:54

If it has something to communicate with the PC, it might not initilize the rest of the stuff before negotiating how much power it can take since its actually being a well behaved USB device for a change from most USB powered tat.

Richard rich.ms

scuwp

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#1757355 6-Apr-2017 07:53

Sorry never tried it, but would suspect that the light is only confirming it has established a connection to the attached computer. No handshake, no light.

Lazy is such an ugly word, I prefer to call it selective participation

shk292

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#1757360 6-Apr-2017 08:15

How about a powered USB hub?

tchart

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#1757379 6-Apr-2017 09:38

shk292:
How about a powered USB hub?

Good call, might try that

Hammerer

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#1757400 6-Apr-2017 10:26

Lots of people have tried to do this before, e.g. see the links below:

http://forum.darkspyro.net/spyro/viewposts.php?topic=73090 is more useful. http://forum.darkspyro.net/spyro/viewposts.php?topic=89841 is related but less useful.

Requires a host connection?

I doubt that a USB hub will make any difference because it sounds like a host controller is required to provide an endpoint. I didn't think that USB hubs have a host controller but I might be wrong. See http://www.beyondlogic.org/usbnutshell/usb1.shtml for a lot more info

When a USB device is plugged in the host sets the connection to the default endpoint 0. Another address is then assigned for other activities. Maybe the Lightcore requires this assignment?

All devices must support endpoint zero. This is the endpoint which receives all of the devices control and status requests during enumeration and throughout the duration while the device is operational on the bus.

Without a host controller you won't have this on any hub.

http://www.beyondlogic.org/usbnutshell/usb3.shtml#Endpoints

Requires a specific message from the host?

More likely that the Lightcore requires a specific message from the host.

gzt

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#1757780 6-Apr-2017 19:28

tchart: I put that in quotes as it powers on when I use any game console, PC, raspberry pi etc USB port. Ive tried several USB wall chargers and no go. It just doesn't power on.

Is there any reason why not a cheap pi and a powered hub?

Dell

Shop now for Dell laptops and other devices (affiliate link).

gzt

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#1757782 6-Apr-2017 19:37

Btw there are specific powered hub recommendations for pi:

http://elinux.org/RPi_Powered_USB_Hubs

tchart

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#1757799 6-Apr-2017 20:54

gzt:
tchart: I put that in quotes as it powers on when I use any game console, PC, raspberry pi etc USB port. Ive tried several USB wall chargers and no go. It just doesn't power on.

Is there any reason why not a cheap pi and a powered hub?

Yep that's how its working now. An orange pi lite to be exact. Its a bit messy though so I'd prefer just to have a walwart to plug in.

Definitely seems to be USB host that is the issue - it works with my Dlink portable router (http://www.dlink.com/uk/en/products/dir-505-shareport-mobile-companion)

tchart

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#1757802 6-Apr-2017 21:00

@Hammerer thanks for the links. Good reading albeit a bit out of date.

The latest series (Imaginators) have these crystals that constantly fade/blink on the portal. So I dont need the host to send any info I just need the portal to be powered on.

Heres a picture of it in action (much better in reality as they blink/fade a different times)