On Sat, 27 Dec 2008 12:56:05 +1100, Franc Zabkar
wrote in
:

On Sat, 27 Dec 2008 11:14:49 +1100, Franc Zabkar
put finger to keyboard and composed:

On Fri, 26 Dec 2008 12:33:36 -0800, Pat Cheney put
finger to keyboard and composed:

One problem I've found with cellphones is Motorola. For some reason,
Motorola USB is "special" USB.

I've found that Motorola chargers work fine with all other phones but
Motorola phones don't work well with the other chargers.

The difference could be just one resistor:
http://pinouts.ru/CellularPhones-A-N...r_pinout.shtml

I also believe that some devices will look for the presence of pullup
or pull-down resistors on the Data+ and/or Data- signal pins. In this
way the device knows when it is connected to a USB host, in which case
it will limit its current draw to 500mA. Otherwise it thinks it is
connected to a fast charger, and then it draws whatever current it
wants.

People, people, enough with the mystery and speculation -- this is part
of the USB standard! It's called ID, and is clearly defined. See
http://en.wikipedia.org/wiki/Universal_serial_bus#USB_cables

--
Very best wishes for the holiday season and for the coming new year,
John