Service_USB 5 - Change USB power use
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## Name

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

## On Entry

R0 | 5 (reason code)
R1 | &80C00 (USB Service call)
R2 | Pointer to controller structure
R3 | USB address of the device which wants to draw/release the current.
R4 | Amount of current in MilliAmps to draw.
R5 |
Value | Operation
0 | Test
1 | Claim
2 | Release

## On Exit

All registers preserved to pass on, else

R0 | 0 for success any other value indicates failure.
R1 | 0 to claim or preserved to pass on.
R2, R3, R4, R5 | preserved

## 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.