Help: ICE_ICELIB_PIC_DMASETUP

Sets up HOST DMA handler

Function PIC_DMASETUP - Sets up HOST DMA handler

PIC	p	Handle to Device 
int	dmac	DMA Channel - usually returned from PIC_IOPORT
int	dir	Transfer direction (1=output/playback, -1=input/acquisition)
DMAMAP	map	DMAMAP structure from PIC_MAPMEM or PIC_MAPFILE
int	block	DMA transfer size in bytes (-1 for internal default)
int	flags	Run-time modifiers

Prepares a DMA channel for HOST<->Processor transfers to/from DMA addresses
obtained through PIC_FILE or PIC_MAPBUF calls.  This downloads DMA parameter
blocks to the Processor and adds the block to a list of active DMA channels for
the Processor interrupt handler to service.  The DMA is initiated by a call to
PIC_DMAFUNC.

By default, PCI transfers are 4 kbytes in length.  For tighter host response 
with low data rates, this can be lowered at the expense of more overhead.  The
minimum transfer length is 64 bytes.