Service_USB 3 - Release USB device interface setting
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Service_USB 3 - Release USB device interface setting

Service_USB 3 - Release USB device interface setting — Application wants to release USB device interface setting

On Entry

R03 (reason code)
R1&80C00 (USB Service call)
R2Pointer to controller structure
R3Pointer to device structure
R4Interface number according USB device Interface descriptor

On Exit

All registers preserved to pass on, else

R00 to refuse access or 1 to cause a re-try later.
R10 to claim or preserved to pass on.
R2, R3, R4preserved

Use

Must be broadcast by an application which wants to change an interface of device to inform other applications using the interface. If rejected with a 1 result the application may wait for a Service_USB 0 and can afterwards retry to do the change.

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Service_USB 2 - Release USB device configuration setting Home Service_USB 4 - Change transfer capacity