USBD_ISO_PACKET_DESCRIPTOR structure (usb.h)

The USBD_ISO_PACKET_DESCRIPTOR structure is used by USB client drivers to describe an isochronous transfer packet.

Syntax

typedef struct _USBD_ISO_PACKET_DESCRIPTOR {
  ULONG       Offset;
  ULONG       Length;
  USBD_STATUS Status;
} USBD_ISO_PACKET_DESCRIPTOR, *PUSBD_ISO_PACKET_DESCRIPTOR;

Members

Offset

Specifies the offset, in bytes, of the buffer for this packet from the beginning of the entire isochronous transfer buffer.

Length

Set by the host controller to indicate the actual number of bytes received from the device for isochronous IN transfers. Length not used for isochronous OUT transfers.

Status

Contains the status, on return from the host controller driver, of this transfer packet.

Remarks

This structure is used as part of an isochronous transfer request to the host controller driver using the _URB_ISOCH_TRANSFER structure. The Offset member contains the offset from the beginning of the TransferBuffer or TransferBufferMDL members of _URB_ISOCH_TRANSFER.

Requirements

Requirement	Value
Header	usb.h (include Usb.h)

See also

How to Transfer Data to USB Isochronous Endpoints

USB Structures

USBD_IsochUrbAllocate

_URB_ISOCH_TRANSFER