COMEDI_DIO_WRITE(3)

✨ COMEDI_DIO_WRITE ✨

okay bestie, welcome to the Comedi reference 💖 this page is all about comedi_dio_write and it's genuinely so simple it's giving main character energy. one bit. one channel. one slay. periodt.

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🌸 NAME 🌸

comedi_dio_write — write single bit to digital channel 💅

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🎀 SYNOPSIS 🎀

#include <comedilib.h>

int comedi_dio_write(comedi_t * device, unsigned int subdevice,
                     unsigned int channel, unsigned int bit);

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🦋 DESCRIPTION 🦋

okay so here's the tea, bestie: this function writes the value bit to the channel channel belonging to the subdevice subdevice of device device. that's it. that's the whole vibe. one bit, one channel, no drama ✨

and lowkey, this function is literally equivalent to:

comedi_data_write(device, subdevice, channel, 0, 0, bit);

iconic. it's the same thing, just wearing a cuter outfit. 🫶

but wait, there's more (there's always more): this function does not require a digital subdevice or a subdevice with a maximum data value of 1 to work properly. so like, don't stress about what kind of subdevice you're dealing with — it'll do its thing anyway. 💜

pro tip moment 🍓: if you wish to write multiple digital channels at once, it is more efficient to use comedi_dio_bitfield2 than to call this function multiple times. like, calling this over and over is giving inefficient ngl. use the bitfield one when you've got a whole group chat of channels to update. iykyk. 😭

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⭐ RETURN VALUE ⭐

the return values and errors are the same as comedi_data_write. no cap, that's literally all it says — go read that one for the juicy details. 💀

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👑 AUTHORS 👑

these are the legends who made this happen, absolute icons the lot of them:

• 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.

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🧚 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. slay.

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. 📬

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fr fr bestie, that's the whole page. go forth and write exactly one bit. you got this. 💖

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signing off from the Comedi manual set — this page is dated 03/20/2026, brought to you by the Comedi crew 🌈🌸💅 ok bye bestie, mwah 🫶