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.

       Éric Piel <piel@delmic.com>
           Author.

COPYRIGHT

       Copyright © 1998-2003 David Schleef
       Copyright © 2001-2003, 2005, 2008 Frank Mori Hess
       Copyright © 2002-2003 Herman Bruyninckx
       Copyright © 2012 Bernd Porr
       Copyright © 2012 Ian Abbott
       Copyright © 2012, 2015 Éric Piel

       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.