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This function initiates an isochronous transfer with a USB device.
USB_TRANSFER IssueIsochTransfer( USB_PIPE hPipe , LPTRANSFER_NOTIFY_ROUTINE lpStartAddress , LPVOID lpvNotifyParameter , DWORD dwFlags , DWORD dwStartingFrame , DWORD dwFrames , LPCDWORD lpdwLengths , LPVOID lpvBuffer , ULONG uBufferPhysicalAddress );
A USB_TRANSFER handle indicates success. NULL indicates failure.
This function initiates an isochronous transfer to a USB device on the specified endpoint. Since isochronous transfers must be executed continuously, a sequence of buffers is provided, one of which is transferred for each frame. There is no limit on the number of buffers that may be provided, though each one must be less than or equal to the maximum packet size for the endpoint.
Note: in Windows CE 2.12, if a USB client driver calls IssueIsochTransfer with the USB_NO_WAIT flag and with a callback function specified in lpStartAddress, then the USB client driver must not call CloseTransferor AbortTransferbefore the isochronous transfer has completed (that is, before the callback function has been invoked).
IssueIsochTransferbehaves either synchronously or asynchronously, depending on the value you provide for lpStartAddressand whether dwFlagscontains the USB_NO_WAIT flag, as shown in the following table:
When behaving asynchronously, the function will invoke your callback function, if one is specified in lpStartAddress, when the transfer is complete.
|Runs on||Versions||Defined in||Include||Link to|
|Windows CE OS||2.10 and later|
Note This API is part of the complete Windows CE OS package as provided by Microsoft. The functionality of a particular platform is determined by the original equipment manufacturer (OEM) and some devices may not support this API.
Last updated on Tuesday, July 13, 2004