Re: USB 5v power from Model A 6v geni/battery
MrTube,
Yes, you are correct. The USB device should start up with a small amount of current, and then negotiate for more...up to 500 MA.
In most applications, that does not happen and the Host just supplies 500 MA or the total that all USB ports could supply...i.e. 2A with 4 ports.
I have a USB CD player that has two USB connections. One communicates to the Host and the other just pulls 500 MA with no communications. In that way, the external CD palyer can get 1A, but Technically, should only get a little over 500 MA.
The USB idea was a great step forward for Computer users, but the implementation is not often "to the spec."
Marc
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