Post Last Edited by dlanor at 2014-9-18 17:06 |
Post Last Edited by roses2at at 2014-9-16 05:25
Could you perhaps please write something in the Wiki at http://wiki.lemaker.org/Android about how you are set up do your tests with this 4.4 image?
roses2at Posted at 2014-9-16 05:03
I think that as someone who has given up on using that Android release I'm the wrong person to document its use.
I tested it in much the same way as I've tested the other releases, except for the notably larger power requirement during bootup. But once I realized that this system is not 'rooted' I lost interest in it, and have not bothered with it since then. (Nor will I...)
I'm really confused about the two power supplies thing - is it really necessary to have two 5V/2A PSUs plugged, one via DC In and the other via OTG?
No, I don't think so. But it is necessary to supply a higher current than is usually required with other BPi system images. I haven't investigated this in detail, but I believe that this system image starts up with a wasteful CPU 'governor', running everything at max speed regardless of the needs. And that kind of operation demands significantly higher PSU current than usual.
Cos I'm sure that I read somewhere else, maybe in this forum, maybe another, that it's a definite no-no to feed ANY kind of power in through OTG.
That obviously varies with different hardware designs. Connecting two independent PSU units to the same load is always a risky business in any case, since it can cause one of the PSU's to 'actively' overload the other, as both try to regulate the same voltage point to slightly different voltage values.
If that is so that you do need two PSUs, is that only for the first boot while it sorts itself out, or for every subsequent boot as well, or all the time while it's running?
I believe the higher current is mainly needed at every boot, since they probably use a turbo mode during bootup.
Or after it reaches the the main screen can you disconnect the OTG power?
That could work, depending on the current rating of the remaining supply.
But disconnecting a PSU during operation means risking a voltage glitch that may crash the CPU.
How stable is it? What is working and what is not working? What specifically causes it to crash? What about WiFi dongles or is only Ethernet cable viable?
These are questions better answered by someone who finds that Android 4.4 release useful, which I do not (since it's not rooted).
And it really would be better to discuss that version in some other thread(s) than this one.
I suggest that for this thread we try to stick to the Android 4.2 version mentioned in the thread title.
Best regards: dlanor