USB Data Pins
Alright, i have finally started an external DIY charger project that i have put off for quite sometime now.
A typical USB cable for the nano-clones has 4 pins, 2 for power supply, 2 for data in/out.
Now, i am able to supply the 5V required for the player to charge. Also, i've measured the current that goes to the player is about 160mA. All these fits a typical USB output rating.
When i connect the player to the DIY charger, the DIY charger appears to be an external battery rather than a charger.
Example, the player shows 1/3 battery life. When connected, the battery life becomes 2/3.
As compared to normal charging via computer or AC adaptor where the battery icon animates, the battery icon now does not animate.
This i assume that the external DIY charger acts as a parallel battery source now?
So the question is, what kind of input does the 2 data pins need? Logic 1 or 0? As i've left it open-circuit at the moment.
Also, is 160mA enough? It is very difficult to measure the current that supplies the player when charging via computer.
Perhaps someone with USB knowledge can answer this?
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Why are clones called MP4 Players, when they don`t play .MP4 at all?
It`s like an MP3 Player which plays Music CDs only.
T39 doesn''t sound as good as my T29
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