Dear All,
I was hoping that I’d be able to give keyboard and mouse input from a Motorola ATRIX Lapdock to the Jetson via its Micro USB port. However, I get no response.
The combined mouse-keyboard works fine when plugged into the USB 3.0 port. I want to use the Micro USB port so I can plug a camera (requiring a high data transfer rate) into the USB 3.0 port and I’d rather not use a double hub.
I’ve found conflicting accounts of how the Micro USB port may be used. Some say it can only be used during force recovery, and others say it can be used by a mouse (eg Jetson TK1 - eLinux.org).
Is there a way that I can activate the Micro USB port so it is responsive to the keyboard-mouse from start-up?
All ideas really appreciated!
You’re probably using the wrong cable type if the port doesn’t work.
The micro-USB port is an “On the Go” (OTG) type. A normal port is either a device or host type, but not both…a type “A” or type “B” would work on a normal port, but not both (function would be dedicated to only one type). OTG ports accept either “A” or “B”, detect which it is, and change function depending on which type is used. The normal cable for a keyboard, mouse, or other peripheral is type “A”, the supplied micro cable is type “B”, which disables normal function and makes it useful only for flash.
Get a micro-A cable and it will work with a normal HUB or peripheral. Or a full-size to micro-A adapter.
Thank you linuxdev!
I found out that the difference between a Micro-A and Micro-B is that the 4th pins are grounded and left unconnected respectively. So after about 2 hours I worked out how to cut open and managed to soldered a wire between the 4th and 5th (Ground) pin of a male micro-b. It now works! But I don’t recommend making the modification, far too fiddly.
I used this cable with success: Amazon.com
The only problem for me is if I plug OTG cable AFTER I boot the system. If I plug the OTG cable before the boot the USB runs at normal speed.
This may be an issue with improper USB wake after it is suspended for reduced power consumption. There have been other issues with USB not waking when it should, usually “fixed” by turning off USB sleep.