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USB ports? Answered

What are all those wires in USB ports used for?

P.S : If I wire 2 USB ports in series, the voltage will not go up, right?



You can't wire the ports up in series, if you could it would still just be 10 volts. The maximum current you can draw is 500ma, however on many ports it's limited to 100ma unless the device requests the extra draw.  

You can experiment with the ports if you fancy, the computer shuts them off if you over draw on current or cause a power surge on them, it'll pop up a warning and you just re-enable the port after disconnecting the circuit that caused the surge. 

The wires work like so:

Black - Ground (0v)
Red - Positive (+5v)
Green/blue - Data
White - Data

The black and red cables are always the same, sometimes data cables are different colours. 

If you try to wire 2 USB ports in series, all you're going to do is short out one of the ports by directly connecting power and ground. If you're lucky you won't burn anything out, but I REALLY wouldn't try it.

The two centre pins are data pins, the outer pins are the +5V and 0V, as shown here.

No, the voltage will not increase. If you need more voltage, you can get chips which increase voltage DC-DC, however it may be more useful to use a 9V battery or two.