debian man page for comedi_dio_bitfield2

COMEDI_DIO_BITFIELD2(3) 					 Comedi reference					   COMEDI_DIO_BITFIELD2(3)

NAME
       comedi_dio_bitfield2 - read/write multiple digital channels

SYNOPSIS
       #include <comedilib.h>

       int comedi_dio_bitfield2(comedi_t * device, unsigned int subdevice, unsigned int write_mask, unsigned int * bits,
				unsigned int base_channel);

DESCRIPTION
       The function comedi_dio_bitfield2 allows multiple channels to be read or written together on a digital input, output, or configurable
       digital I/O device. The parameter write_mask and the value pointed to by bits are interpreted as bit fields, with the least significant bit
       representing channel base_channel. For each bit in write_mask that is set to 1, the corresponding bit in *bits is written to the digital
       output channel. After writing all the output channels, each channel is read, and the result placed in the approprate bits in *bits. The
       result of reading an output channel is the last value written to the output channel.

       All the channels might not be read or written at the exact same time. For example, the driver may need to sequentially write to several
       registers in order to set all the digital channels specified by the write_mask and base_channel parameters.

RETURN VALUE
       If successful, 0 is returned, otherwise -1.

AUTHORS
       David Schleef <ds@schleef.org>
	   Author.

       Frank Mori Hess <fmhess@users.sourceforge.net>
	   Author.

       Herman Bruyninckx <Herman.Bruyninckx@mech.kuleuven.ac.be>
	   Author.

       Bernd Porr <tech@linux-usb-daq.co.uk>
	   Author.

       Ian Abbott <abbotti@mev.co.uk>
	   Author.

COPYRIGHT
       Copyright (C) 1998-2003 David Schleef
       Copyright (C) 2001-2003, 2005, 2008 Frank Mori Hess
       Copyright (C) 2002-2003 Herman Bruyninckx
       Copyright (C) 2012 Bernd Porr
       Copyright (C) 2012 Ian Abbott

       This document is part of Comedilib. In the context of this document, the term "source code" as defined by the license is interpreted as the
       XML source.

       This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as
       published by the Free Software Foundation, version 2.1 of the License.

       This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

       You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software
       Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.

Comedi								    07/06/2012						   COMEDI_DIO_BITFIELD2(3)