LibUsbDotNet 2.2.8
RequestType Field
Library Reference ► LibUsbDotNet.Main ► UsbSetupPacket ► RequestType
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This bitmapped field identifies the characteristics of the specific request. In particular, this field identifies the direction of data transfer in the second phase of the control transfer. The state of the Direction bit is ignored if the wLength field is zero, signifying there is no Data stage.
The USB Specification defines a series of standard requests that all devices must support. In addition, a device class may define additional requests. A device vendor may also define requests supported by the device.
Requests may be directed to the device, an interface on the device, or a specific endpoint on a device. This field also specifies the intended recipient of the request. When an interface or endpoint is specified, the wIndex field identifies the interface or endpoint.
Declaration Syntax
C# | Visual Basic | Visual C++ |
Remarks
- Characteristics of request:
- D7: Data transfer direction
- 0 = Host-to-device
- 1 = Device-to-host
- D6...5: Type
- 0 = Standard
- 1 = Class
- 2 = Vendor
- 3 = Reserved
- D4...0: Recipient
- 0 = Device
- 1 = Interface
- 2 = Endpoint
- 3 = Other
- 4...31 = Reserved