Gordons Projects posted about testing and setting the USB current limiter on the new Raspberry Pi B+.
One of the features of the new Raspberry Pi B+ is improved power handling – particularly round the USB interfaces. There is a device connected to the power to the USB ports that is quite clever – it controls the power and “soft starts” the peripherals plugged in. This helps to reduce any brown-outs on the main Pi supply, so reducing the chance of the Pi rebooting when you plug in a USB peripheral with the Pi turned on.
Additionally, it can also limit the total current drawn by the USB peripherals. This is 600mA by default, but can be increased to 1.2A via software.
Warning: DO NOT do this on a whim. Only do this if you are absolutely sure that you need to do it!
But if you do need it, then “How?” I hear you ask… Well, simple… There are 2 ways.
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