USBLib_CtrlMsg (SWI &56340)
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## Name

USBLib_CtrlMsg (SWI &56340) — Starts a transaction using a formatted control message.

## On Entry

R0 | pipe
R1 | Data URB (0 if no data to be transfered)
R2 | Message URB
R3 | waiting template
R4 | bmRequestType (8bit)
R5 | bRequest (8bit)
R6 | wValue (16bit)
R7 | wIndex (16bit)

## On Exit

R0 | waiting
R1,R2,R3,R4,R5,R6,R7 | Preserved

## Use

This call starts a USB control transaction by taking the supplied values and creating the properly formatted control message in the supplied URB (R2) then starting a transaction with the appropriate parameters.

## Related SWIs

USB_RequestStart (SWI&5538F)

## Related Information

Section 8.2.1

usb_request_start

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