USBDevice.controlTransferIn()

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

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.

Syntax

var promise = USBDevice.controlTransferIn(setup, length)

Parameters

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.

Return value

promise that resolves with a USBInTransferResult.

Specifications

Specification
WebUSB API
# ref-for-dom-usbdevice-controltransferin

Browser compatibility

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