RE: Mbed.org on phones.

DAB — Sun, 02 Jun 2013 20:13:02 GMT

Hi Nico,

I suspect that the phones do not have enough power to spare to power another device.

As I recall, most use the USB connect to charge themselves, so they might have a diode in the circuit to make the path one way.

If you made a unique USB cable with a separate power source, either 12 VDC or from the Car auxiliary port, you could then power both devices from the vehicle battery and support just the communication over the line.

Either way, I am not sure it would be worth the effort.

Still, you could set up some interesting sensors using the Freedom board attached to a smart phone for the user interface. You would still need a separate power source, but if you built it into a small case, you could easily slip in a 9 Vdc battery.

Thanks for sharing. If nothing else, you have saved others the time to go down the dry well. [View:/resized-image/__size/16x16/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-9b922d34-f68d-4b0d-ae4f-8f20e833ea89/contentimage_5F00_938.png:16:16]

Have you had any time to look at using mbed to develope code for the Freedom board?

Thanks

DAB

RE: Mbed.org on phones.

shabaz — Sun, 02 Jun 2013 12:53:29 GMT

Hi Nico,

It's interesting it didn't power it I'm wondering if maybe the cable doesn't have the ID pin grounded on the phone end (apparently USB OTG requires this to recognize the host end, see here). It does sound hard to do development work on a small device. Still, as you likely already know, using the FRDM board as some USB accessory (e.g. HID) is possible, although that's not your goal here of course. Also, this link shows the FRDM board as the host (using OTG capability), and a mouse connected to it.

Digressing a bit more, there is also android development kit of course, that uses the attached device in host mode and has to then supply power instead of the phone. I've not done any android development, but should be possible to interface the BeagleBone to Android. I found this link which was interesting (the links on that page have more information).