[PLUG] Scanner dependent on USB port [RESOLVED]

[Rich Shepard]

On Sun, 2 Feb 2020, Galen Seitz wrote:

> I suspect you are over the power budget for your bus-powered hub.

Galen,

I never considered this.

> Before trying sane, I suggest using lsusb to check for the scanner. This
> command will tell you how much power every USB device is requesting. Look
> for your hub and the connected devices and add up the current. The limit
> for USB 3.0 is 900 mA total current.
> lsusb -v |grep 'idVendor\|idProduct\|MaxPower'

> Try it with the scanner connected in both places just in case the scanner 
> doesn't even appear when connected to the hub.

Yep:

Scanner on hub:
     MaxPower              100mA
     MaxPower              500mA
     MaxPower              100mA
     MaxPower              100mA
Scanner on front:
     MaxPower              100mA
     MaxPower              500mA
     MaxPower              100mA
     MaxPower              100mA
     MaxPower              500mA

The last one being the scanner.

> Given what you have connected, I think the solution is probably going to
> be connecting power to the hub.

Sure enough. Now to find where I put the power cable.

Thanks very much,

Rich