cbi()

Abstract

The cbi() is a macro to set the bit(the second argument) of the address(the first argument) to 0.

Source Code

The cbi() is defined in hardware/arduino/avr/cores/arduino/wiring_private.h as below.

1

#define cbi(sfr, bit) (_SFR_BYTE(sfr) &= ~_BV(bit))

It sets the bit-th bit of the content of sfr to 0.

The _SFR_BYTE() is a macro that returns a byte of data of the specified address. The _BV() is a macro that shifts 1 to left by the specified numnber.

バージョン

Arduino AVR Boards 1.8.6

License

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/*
  Copyright (c) 2016 garretlab.
  Added source code explanation by garretlab.
*/

/*
  wiring_private.h - Internal header file.
  Part of Arduino - http://www.arduino.cc/

  Copyright (c) 2005-2006 David A. Mellis

  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; either
  version 2.1 of the License, or (at your option) any later version.

  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
*/

Last Update

July 31, 2025