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View Full Version : [All iPads] Lightning to MicroUSB + USB OTG/Host




atkinchris
Nov 27, 2012, 12:10 PM
Hello!

This is probably something very few have even thought about, but I was curious, so I did some investigation.

My query was; what else can you do with the Lightning to MicroUSB adapter from Apple? We already knew it could do charging and sync, but what about usb host functions or even (at an absurd long shot) MHL?

I knew from experience that the Camera Connector kit USB for the 30 pin iPad's allowed a large number of mass storage devices to work, provided there was enough power. Furthermore these devices worked in apps such as Goodreader, in order to transfer more file types than just photos. Also, other users had found that USB keyboards (both typing and musical), MIDI equipment, microphones and a small host of other devices also worked with the Camera Kit (app permitting). This expanded the usefulness of that little USB port, and the functionality of the iPad.

I knew that Lightning could support USB host mode. That was clear from the Camera Connector Kit USB for Lightning. Early reports were also coming in that audio equipment and keyboards were still also working. However; could it support these functions through the Micro USB adapter, when joined to a USB on-the-go cable?

The answer is sadly, no. After personal testing the Micro USB adapter can only be used for charging and sync. Connecting an OTG cable and a USB stick, camera, or other device has no effect; in fact, no power or signal was given to the attached devices (even with a powered hub). MHL cables do equally little.

This does make sense, given that for plain USB, the sense pin must be used to invoke host mode. Lightning must be similar in that it requires some signal from the device (presumably from the chip in the connector) to switch to host mode. I can only assume that all of this is also true for the 30 pin to Micro USB port, as I don't have one to test.

I'd be interested to hear if anyone else has played around with the new Lightning Camera USB kit to see what range of devices are working.