LPGET_ISOCH_RESULTS (Compact 2013)

3/26/2014

This function gets the status of an active isochronous transfer.

Syntax

typedef BOOL (* LPGET_ISOCH_RESULTS)(
  USB_TRANSFER hTransfer,
  DWORD cFrames,
  LPDWORD lpdwBytesTransferred,
  LPDWORD lpdwErrors
);

Parameters

• hTransfer
  [in] Handle to an isochronous transfer.

• cFrames
  [in] Number of frames to return.

• lpdwBytesTransferred
  [out] Pointer to an array of lengths. This pointer might be NULL, in which case this function does not report bytes-transferred information.

• lpdwErrors
  [out] Pointer to an array of error values. This pointer might be NULL, in which case this function does not report error value information.

  The following table shows the possible error codes for UHCI.

  Error code	Value
  USB_NO_ERROR	0x00000000
  USB_STALL_ERROR	0x00000004
  USB_NOT_COMPLETE_ERROR	0x00000103

  For OHCI, the hardware writes the error status into the buffer. The following table shows the possible error codes for OHCI.

  Error code	Value
  USB_NO_ERROR	0x00000000
  USB_CRC_ERROR	0x00000001
  USB_BIT_STUFFING_ERROR	0x00000002
  USB_DATA_TOGGLE_MISMATCH_ERROR	0x00000003
  USB_STALL_ERROR	0x00000004
  USB_DEVICE_NOT_RESPONDING_ERROR	0x00000005
  USB_PID_CHECK_FAILURE_ERROR	0x00000006
  USB_UNEXPECTED_PID_ERROR	0x00000007
  USB_DATA_OVERRUN_ERROR	0x00000008
  USB_DATA_UNDERRUN_ERROR	0x00000009
  USB_BUFFER_OVERRUN_ERROR	0x0000000C
  USB_BUFFER_UNDERRUN_ERROR	0x0000000D
  USB_NOT_ACCESSED_ERROR Note: HCD maps USB_NOT_ACCESSED_ALT to USB_NOT_ACCESSED_ERROR.	0x0000000E

Return Value

Returns TRUE if hTransfer points to a completed isochronous transfer. Otherwise, returns FALSE.

Remarks

The supplied arrays are filled out with the error values and amounts of data transferred for each frame. There might have been data transferred on a frame, even if lpdwErrors containserrors.

Requirements

Header

usbdi.h

See Also

Reference

USB Driver Functions