INativeListener.OnIsochTransfer Method

Native (C++):

HRESULT OnIsochTransfer ( _FILETIME * fTime,void * Data,unsigned long Size,unsigned long nTransferFlags,unsigned long StartFrame,unsigned long NumberOfPackets,unsigned long ErrorCount) ;

Parameters

fTime The time of the event. Data Pointer to a USBPACKET. Use it to manually parse all fields. See MFCSample for more details. Size Total size of USBPACKET and all payload data. Equals to nSize variable:

C++

          USBPACKET packet;
          ULONG nSize = packet->Size;

          USBPACKET_URB* pUrb = (USBPACKET_URB*)packet;
          ATLASSERT(pUrb->Size==nSize);

nTransferFlags Specifies zero, one, or a combination of the following flags:USBD_TRANSFER_DIRECTION_IN\USBD_SHORT_TRANSFER_OK\USBD_START_ISO_TRANSFER_ASAP. StartFrame Specifies the frame number the transfer should begin on. This variable must be within a system-defined range of the current frame. The range is specified by the constant USBD_ISO_START_FRAME_RANGE. If START_ISO_TRANSFER_ASAP is set in TransferFlags, this member contains the frame number that the transfer began on, when the request is returned by the host controller driver. Otherwise, this member must contain the frame number that this transfer will begin on. NumberOfPackets Specifies the number of packets described by the variable-length array member IsoPacket. ErrorCount Contains the number of packets that completed with an error condition on return from the host controller driver.

Return Value

S_OK or standard OLE error code.

Remarks

Fired when URB packet with urb.UrbHeader.Function=URB_FUNCTION_ISOCH_TRANSFER is received. See _URB_ISOCH_TRANSFER and USBD_ISO_PACKET_DESCRIPTOR for more details. The library decodes several parameters from this packet (see above).

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