USBDevice.controlTransferIn()

The controlTransferIn() method of the USBDevice interface returns a promise that resolves with a USBInTransferResult when the result of a command or status request has been received from the USB device.

var promise = USBDevice.controlTransferIn(setup, length)

setup 

An object that sets options for . The available options are:

• requestType: Must be one of three values specifying whether the tranfer is "standard" (common to all USB devices) "class" (common to an industry-standard class of devices) or "vendor".
• recipient: Specifices the target of the transfer on the device, one of "device", "interface", "endpoint", or "other".
• request: A vendor-specific command.
• value: Vender-specific request parameters.
• index: The interface number of the recipient.

length

The maximum number of bytes to read from the device. The actual data is in the USBInTransferResult in the resolved Promise.

promise that resolves with a USBInTransferResult.