Quote:
Originally Posted by curstpriest
My computer -> Select drive that resembles kindle -> Eject (only way)
DO NO USE SAFELY REMOVE HARDWARE
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Only if you're using Windows Vista or Windows 7. Amazon tell you to use safely remove hardware if you're running XP.
Quote:
Originally Posted by curstpriest
All the wall charger is, is a ac to dc transformer that outputs 4.9v dc.
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It isn't quite that simple. USB chargers to reduce costs don't include a processor to handle the USB power negotiation system. This means that the device needs to be able to tell whether the charger itself is capable of supplying the requested current. The way they did this was to do very basic signalling based on the voltage present on the data lines. Specific voltages indicate what current the charger is capable of supplying.
There are many devices now which charge via USB and are capable of charging faster if they are supplied with more than the maximum 500mA per port that USB 1 and USB 2.0 specify. You're allowed to supply more than that if you want and most of the USB decoration devices rely on that to operate though. This detection happens either via negotiation with the computer using the USB protocol or via the signalling system I mentioned previously. A device should connect in low power mode which at most draws 100mA and request more power from the host. If this is granted then it can enter full power mode and draw whatever it negotiated. The UK Kindle charger is capable of supplying 850mA at 5V which corresponds to a faster charge.
If the USB data lines aren't connected correctly or aren't connected in the expected manner then some devices will refuse to charge. An example would be iPhones and iPod touches. They won't charge properly if it isn't connected to a computer or a correctly wired charger. If you do connect it to an official Apple charger then it knows that it can charge at 1A instead of 500mA and it is significantly quicker.
Quote:
Originally Posted by curstpriest
You should be able to charge your kindle/ipod/any usb device even while your computer is off. The power supply (if it's on) still supplies power to the motherboard, and over the 5v rail, so your USB gets power.
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The 5V standby line from your PSU is generally only rated for around 500-1000mA in total which includes whatever your motherboard itself needs and any devices attached to it. This means you can't go crazy with plugging in multiple devices to charge off the USB ports when the machine is off. Your screenshot is only showing the main 5V line and not the 5VSB line from the PSU.