Service_USB 5 - Change USB power use
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Service_USB 5 - Change USB power use

Service_USB 5 - Change USB power use — Claim/release USB power capacity

On Entry

R05 (reason code)
R1&80C00 (USB Service call)
R2Pointer to controller structure
R3USB address of the device which wants to draw/release the current.
R4Amount of current in MilliAmps to draw.
R5

ValueOperation
0Test
1Claim
2Release

On Exit

All registers preserved to pass on, else

R00 for success any other value indicates failure.
R10 to claim or preserved to pass on.
R2, R3, R4, R5preserved

Use

Must be launched by a configuration application. The USB Hub class driver Module is the only program which must claim this Service call. If operation is successful (that means capacity is available, releases are always successful) a 0 will be filled into R0.

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Service_USB 4 - Change transfer capacity Home Service_USB 7 - Sub host controller driver has been started.