Fast charging and the resistor trick

[Andy Green]

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Somebody in the thread at some point said:
| Hi,
|
| I have a microcontroller based USB device and want to connect it to the
| Freerunner (in host mode). Now I need some clarifications on the resistor
| trick:
|
| The two 15k Ohm resistors are indispensable to comply with USB-spec?

Yes, for reliable detection of the device presence.

| What will happen if I connect the device (with the resistors) to the
USB port
| of my computer? (The external power supply is turned of)

It should be fine.

| How do I have to design the USB endpoints on the device, so the
Freerunner
| does charge with 1A? Or do I need the 47k Ohm resistor if the FR is in
host
| mode?

Only the 47K resistor is looked for to see if a charger is around.

| At
|
http://wiki.openmoko.org/wiki/Specialized_USB_cables#How_to_make_a_USB_cable_for_powering_attached_USB_devices_and_charging_the_Neo_while_in_host_mode_.28aka_Y-
| Cable.29
| it is written that "Future kernels should switch to hostmode +
external power
| when seeing this 47k resistor." Is this already implemented?

Nope.

| Furthermore, it is mentioned that the resistors can be used to avoid
suspend
| of the Freerunner. I hope, I still can suspend if I want?

No idea what the author of that page is on about there, none of this
will impact either USB suspend or device suspend.

- -Andy
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