Alexey Feldgendler wrote:
On Fri, 18 Apr 2008 21:06:26 +0200, Michael Shiloh
<[EMAIL PROTECTED]> wrote:
* you mention 'other manufacturers' that 'identify their own
chargers' with various resistors... if I have one of those chargers,
is there a way to get the phone to ID it?
There are two issues here: First of all, you have to know the value
and location (i.e. between which two pins) of the resistor. There is
no standard, no gathering place of all this information. You can
search the Internet in case someone has posted this.
I'm not sure how we measure the resistor. My guess is we measure the
current and deduce from this. Measuring the current requires an analog
to digital converter (ADC), which we must have wired up to the pin in
question. If an arbitrary charger uses a different pin, and if we
don't have an ADC on that pin, we won't be able to detect the resistor
there.
That said, the most common location for a resistor is the same as
ours, so you're in good shape.
Next, you have to modify the code to do this. Trivial for all you
developers.
This could actually be done by an application downloadable by a user who
knows what he's doing. The user starts the application, plugs in the
charger, the application measures the resistance. If it's not something
identifiable, too bad. Otherwise, the user reads the output current
specification on the charger and adds the pair (ID resistance, current)
to the table.
That's a great idea. Find the code that checks for the specific
Freerunner resistance, and modify it to simply report the value of
whatever it sees. If it is anything different from an open or short
circuit (within reasonable tolerances) assume it is a resistor, and note
the value. Post to the wiki, and if a few other people see the same
value for the same charger, this seems safe to code.
The reason I think this is of limited use is that I would guess that
most of you will simply read the label on the charger, and then use a
utility to override all the automatic detection and simply tell the
charging logic that 500mA or 1A is available. Automating this is a lot
of work for little gain.
Not so little if you have a particular charger (say, Motorola) and use
it to charge Neo every time. You'd really want it to auto-detect the
charger instead of choosing the charging current manually every time.
Yes, that's a really good point, and one I had overlooked.
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