Index for Section 9

Alphabetical listing for V

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vba_get_info(9r)
NAME
  vba_get_info - VMEbus: Returns the VMEbus adapter type and characteristics

SYNOPSIS
  unsigned_int vba_get_info(
	  struct controller *ctlr );

ARGUMENT
  ctlr
      Specifies a pointer to the VMEbus device's controller data structure.

DESCRIPTION
  The vba_get_info() routine returns flags, defined in vbareg.h, that
  indicate the VMEbus adapter type, whether the adapter supports hardware
  byte swapping, and whether the system is byte and word I/O capable.

RETURN VALUES
  The vba_get_info() routine returns an unsigned integer that can be tested
  for the following flag values, among others (see vbareg.h for a complete
  list):

  _____________________________________________________________________________
  Flag Category		     Value		   Meaning
  _____________________________________________________________________________
  Adapter type flags	     VBA_TYPE_VIPVIC	   VIP/VIC adapter
			     VBA_TYPE_UNIV	   UNIVERSE II adapter
  Byte swapping flags	     VBA_HW_BYTE_SWAP

						   The adapter supports
						   hardware byte swapping


			     VBA_NO_HW_BYTE_SWAP

						   The adapter does not support
						   hardware byte swapping
			     VBA_BW_CAPABLE

  Byte and word I/O
  capable flags


						   The system is byte and word
						   I/O capable


			     VBA_NOT_BW_CAPABLE

						   The system is not byte and
						   word I/O capable
  Error flag		     -1

						   The adapter does not support
						   the vba_get_info() routine
  _____________________________________________________________________________

EXAMPLE
  The following code fragment shows a call to the vba_get_info() routine to
  determine whether hardware byte swapping is supported by the system's
  VMEbus adapter; if not, a flag is set to indicate that software byte
  swapping may be required:

       .
       .
       .

       if ((vba_get_info(ctlr) & VBA_BYTE_SWAP_MSK) == VBA_NO_HW_BYTE_SWAP)
	 dmaex_sw_byte_swap = 1;

       .
       .
       .


  The driver example chapter of Writing VMEbus Device Drivers shows how the
  dmaex example driver calls vba_get_info() to test the VMEbus adapter's byte
  swapping capability.	If the adapter cannot perform hardware byte swapping,
  the user-level code associated with the example driver will perform
  software byte swapping when needed to fulfill a transfer request.  See the
  example of programming user-level software byte swapping in the driver
  example chapter.

Index for Section 9

Alphabetical listing for V

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