Help: ICE_ICELIB_PIC_DMAXFER

Transfers next available data to/from the host circular buffer

Function PIC_DMAXFER - Transfers next available data to/from the host circular buffer

PIC	p	Handle to Device 
int	dmac	DMA Channel - usually returned from PIC_IOPORT
int	*buffer Pointer to transfer buffer
int	bytes   Number of bytes in transfer buffer
int	flags   Operational modifiers (FLG_NOWAIT=nonblocking)
int	PIC_DMAXFER Number of bytes transferred 

This routine handles the book-keeping for transferring data into or out of
the DMA channel's circular buffer on the host.  The host buffer should be a
multiple of the transfer length.  The routine polls the status registers on 
the card and transfers data when a full transfer is possible.

This routine returns the number of bytes transferred, 0 if no data is transferred and
the FLG_NOWAIT is specified, -1 when the DMA function is completed, and -2 for an error.

Note: If a timeout TO=N flag is specified in the open string, and no data is transfered 
within N seconds, the routine will return with status=0.