The latest version of this library may be found at: http://www.pjrc.com/teensy/td_libs_OneWire.html

OneWire has been maintained by Paul Stoffregen (paul@.nosp@m.pjrc.nosp@m..com) since January 2010. At the time, it was in need of many bug fixes, but had been abandoned the original author (Jim Studt). None of the known contributors were interested in maintaining OneWire. Paul typically works on OneWire every 6 to 12 months. Patches usually wait that long. If anyone is interested in more actively maintaining OneWire, please contact Paul.

Version 2.2: Teensy 3.0 compatibility, Paul Stoffregen, paul@.nosp@m.pjrc.nosp@m..com Arduino Due compatibility, http://arduino.cc/forum/index.php?topic=141030 Fix DS18B20 example negative temperature Fix DS18B20 example's low res modes, Ken Butcher Improve reset timing, Mark Tillotson Add const qualifiers, Bertrik Sikken Add initial value input to crc16, Bertrik Sikken Add target_search() function, Scott Roberts

Version 2.1: Arduino 1.0 compatibility, Paul Stoffregen Improve temperature example, Paul Stoffregen DS250x_PROM example, Guillermo Lovato PIC32 (chipKit) compatibility, Jason Dangel, dangel.jason AT gmail.com Improvements from Glenn Trewitt:

crc16() now works
check_crc16() does all of calculation/checking work.
Added read_bytes() and write_bytes(), to reduce tedious loops.
Added ds2408 example. Delete very old, out-of-date readme file (info is here)

Version 2.0: Modifications by Paul Stoffregen, January 2010: http://www.pjrc.com/teensy/td_libs_OneWire.html Search fix from Robin James http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1238032295/27#27 Use direct optimized I/O in all cases Disable interrupts during timing critical sections (this solves many random communication errors) Disable interrupts during read-modify-write I/O Reduce RAM consumption by eliminating unnecessary variables and trimming many to 8 bits Optimize both crc8 - table version moved to flash

Modified to work with larger numbers of devices - avoids loop. Tested in Arduino 11 alpha with 12 sensors. 26 Sept 2008 – Robin James http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1238032295/27#27

Updated to work with arduino-0008 and to include skip() as of 2007/07/06. –RJL20

Modified to calculate the 8-bit CRC directly, avoiding the need for the 256-byte lookup table to be loaded in RAM. Tested in arduino-0010 – Tom Pollard, Jan 23, 2008

Jim Studt's original library was modified by Josh Larios.

Tom Pollard, polla.nosp@m.rd@a.nosp@m.lum.m.nosp@m.it.e.nosp@m.du, contributed around May 20, 2008

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Much of the code was inspired by Derek Yerger's code, though I don't think much of that remains. In any event that was.. (copyleft) 2006 by Derek Yerger - Free to distribute freely.

The CRC code was excerpted and inspired by the Dallas Semiconductor sample code bearing this copyright.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL DALLAS SEMICONDUCTOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Except as contained in this notice, the name of Dallas Semiconductor shall not be used except as stated in the Dallas Semiconductor Branding Policy.