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annotate service/arduinoNode/arduino-libraries/OneWire/OneWire.cpp @ 991:c6989dcf1f4f

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temp sensor try to work with idle loop (but there are still stutters) Ignore-this: d3d33548db6ce6c329f8aef2cd83403a darcs-hash:20150708082102-312f9-ea553ff8ce011065b93ed3dae5dbc8fa057ca0d8
author drewp <drewp@bigasterisk.com>
date Wed, 08 Jul 2015 01:21:02 -0700
parents 4f5825a9fc47
children
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1 /*
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2 Copyright (c) 2007, Jim Studt (original old version - many contributors since)
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3
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4 The latest version of this library may be found at:
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5 http://www.pjrc.com/teensy/td_libs_OneWire.html
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6
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7 OneWire has been maintained by Paul Stoffregen (paul@pjrc.com) since
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8 January 2010. At the time, it was in need of many bug fixes, but had
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9 been abandoned the original author (Jim Studt). None of the known
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10 contributors were interested in maintaining OneWire. Paul typically
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11 works on OneWire every 6 to 12 months. Patches usually wait that
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12 long. If anyone is interested in more actively maintaining OneWire,
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13 please contact Paul.
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14
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15 Version 2.2:
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16 Teensy 3.0 compatibility, Paul Stoffregen, paul@pjrc.com
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17 Arduino Due compatibility, http://arduino.cc/forum/index.php?topic=141030
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18 Fix DS18B20 example negative temperature
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19 Fix DS18B20 example's low res modes, Ken Butcher
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20 Improve reset timing, Mark Tillotson
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21 Add const qualifiers, Bertrik Sikken
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22 Add initial value input to crc16, Bertrik Sikken
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23 Add target_search() function, Scott Roberts
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24
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25 Version 2.1:
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26 Arduino 1.0 compatibility, Paul Stoffregen
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27 Improve temperature example, Paul Stoffregen
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28 DS250x_PROM example, Guillermo Lovato
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29 PIC32 (chipKit) compatibility, Jason Dangel, dangel.jason AT gmail.com
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30 Improvements from Glenn Trewitt:
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31 - crc16() now works
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32 - check_crc16() does all of calculation/checking work.
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33 - Added read_bytes() and write_bytes(), to reduce tedious loops.
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34 - Added ds2408 example.
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35 Delete very old, out-of-date readme file (info is here)
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36
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37 Version 2.0: Modifications by Paul Stoffregen, January 2010:
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38 http://www.pjrc.com/teensy/td_libs_OneWire.html
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39 Search fix from Robin James
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40 http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1238032295/27#27
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41 Use direct optimized I/O in all cases
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42 Disable interrupts during timing critical sections
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43 (this solves many random communication errors)
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44 Disable interrupts during read-modify-write I/O
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45 Reduce RAM consumption by eliminating unnecessary
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46 variables and trimming many to 8 bits
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47 Optimize both crc8 - table version moved to flash
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48
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49 Modified to work with larger numbers of devices - avoids loop.
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50 Tested in Arduino 11 alpha with 12 sensors.
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51 26 Sept 2008 -- Robin James
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52 http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1238032295/27#27
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53
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54 Updated to work with arduino-0008 and to include skip() as of
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55 2007/07/06. --RJL20
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56
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57 Modified to calculate the 8-bit CRC directly, avoiding the need for
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58 the 256-byte lookup table to be loaded in RAM. Tested in arduino-0010
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59 -- Tom Pollard, Jan 23, 2008
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60
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61 Jim Studt's original library was modified by Josh Larios.
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62
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63 Tom Pollard, pollard@alum.mit.edu, contributed around May 20, 2008
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64
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65 Permission is hereby granted, free of charge, to any person obtaining
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66 a copy of this software and associated documentation files (the
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67 "Software"), to deal in the Software without restriction, including
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68 without limitation the rights to use, copy, modify, merge, publish,
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69 distribute, sublicense, and/or sell copies of the Software, and to
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70 permit persons to whom the Software is furnished to do so, subject to
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71 the following conditions:
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72
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73 The above copyright notice and this permission notice shall be
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74 included in all copies or substantial portions of the Software.
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75
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76 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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77 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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78 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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79 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
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80 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
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81 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
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82 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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83
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84 Much of the code was inspired by Derek Yerger's code, though I don't
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85 think much of that remains. In any event that was..
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86 (copyleft) 2006 by Derek Yerger - Free to distribute freely.
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87
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88 The CRC code was excerpted and inspired by the Dallas Semiconductor
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89 sample code bearing this copyright.
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90 //---------------------------------------------------------------------------
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91 // Copyright (C) 2000 Dallas Semiconductor Corporation, All Rights Reserved.
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92 //
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93 // Permission is hereby granted, free of charge, to any person obtaining a
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94 // copy of this software and associated documentation files (the "Software"),
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95 // to deal in the Software without restriction, including without limitation
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96 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
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97 // and/or sell copies of the Software, and to permit persons to whom the
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98 // Software is furnished to do so, subject to the following conditions:
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99 //
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100 // The above copyright notice and this permission notice shall be included
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101 // in all copies or substantial portions of the Software.
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102 //
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103 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
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104 // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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105 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
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106 // IN NO EVENT SHALL DALLAS SEMICONDUCTOR BE LIABLE FOR ANY CLAIM, DAMAGES
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107 // OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
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108 // ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
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109 // OTHER DEALINGS IN THE SOFTWARE.
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110 //
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111 // Except as contained in this notice, the name of Dallas Semiconductor
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112 // shall not be used except as stated in the Dallas Semiconductor
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113 // Branding Policy.
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114 //--------------------------------------------------------------------------
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115 */
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116
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117 #include "OneWire.h"
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118
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119
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120 OneWire::OneWire(uint8_t pin)
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121 {
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122 pinMode(pin, INPUT);
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123 bitmask = PIN_TO_BITMASK(pin);
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124 baseReg = PIN_TO_BASEREG(pin);
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125 #if ONEWIRE_SEARCH
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126 reset_search();
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127 #endif
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128 }
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129
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130
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131 // Perform the onewire reset function. We will wait up to 250uS for
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132 // the bus to come high, if it doesn't then it is broken or shorted
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133 // and we return a 0;
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134 //
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135 // Returns 1 if a device asserted a presence pulse, 0 otherwise.
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136 //
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137 uint8_t OneWire::reset(void)
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138 {
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139 IO_REG_TYPE mask = bitmask;
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
140 volatile IO_REG_TYPE *reg IO_REG_ASM = baseReg;
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
141 uint8_t r;
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
142 uint8_t retries = 125;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
143
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
144 noInterrupts();
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
145 DIRECT_MODE_INPUT(reg, mask);
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
146 interrupts();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
147 // wait until the wire is high... just in case
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
148 do {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
149 if (--retries == 0) return 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
150 delayMicroseconds(2);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
151 } while ( !DIRECT_READ(reg, mask));
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
152
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
153 noInterrupts();
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
154 DIRECT_WRITE_LOW(reg, mask);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
155 DIRECT_MODE_OUTPUT(reg, mask); // drive output low
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
156 interrupts();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
157 delayMicroseconds(480);
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
158 noInterrupts();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
159 DIRECT_MODE_INPUT(reg, mask); // allow it to float
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
160 delayMicroseconds(70);
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
161 r = !DIRECT_READ(reg, mask);
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
162 interrupts();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
163 delayMicroseconds(410);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
164 return r;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
165 }
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
166
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
167 //
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
168 // Write a bit. Port and bit is used to cut lookup time and provide
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
169 // more certain timing.
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
170 //
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
171 void OneWire::write_bit(uint8_t v)
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
172 {
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
173 IO_REG_TYPE mask=bitmask;
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
174 volatile IO_REG_TYPE *reg IO_REG_ASM = baseReg;
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
175
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
176 if (v & 1) {
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
177 noInterrupts();
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
178 DIRECT_WRITE_LOW(reg, mask);
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
179 DIRECT_MODE_OUTPUT(reg, mask); // drive output low
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
180 delayMicroseconds(10);
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
181 DIRECT_WRITE_HIGH(reg, mask); // drive output high
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
182 interrupts();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
183 delayMicroseconds(55);
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
184 } else {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
185 noInterrupts();
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
186 DIRECT_WRITE_LOW(reg, mask);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
187 DIRECT_MODE_OUTPUT(reg, mask); // drive output low
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
188 delayMicroseconds(65);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
189 DIRECT_WRITE_HIGH(reg, mask); // drive output high
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
190 interrupts();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
191 delayMicroseconds(5);
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
192 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
193 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
194
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
195 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
196 // Read a bit. Port and bit is used to cut lookup time and provide
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
197 // more certain timing.
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
198 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
199 uint8_t OneWire::read_bit(void)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
200 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
201 IO_REG_TYPE mask=bitmask;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
202 volatile IO_REG_TYPE *reg IO_REG_ASM = baseReg;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
203 uint8_t r;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
204
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
205 noInterrupts();
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drewp <drewp@bigasterisk.com>
parents:
diff changeset
206 DIRECT_MODE_OUTPUT(reg, mask);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
207 DIRECT_WRITE_LOW(reg, mask);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
208 delayMicroseconds(3);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
209 DIRECT_MODE_INPUT(reg, mask); // let pin float, pull up will raise
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
210 delayMicroseconds(10);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
211 r = DIRECT_READ(reg, mask);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
212 interrupts();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
213 delayMicroseconds(53);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
214 return r;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
215 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
216
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
217 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
218 // Write a byte. The writing code uses the active drivers to raise the
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
219 // pin high, if you need power after the write (e.g. DS18S20 in
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
220 // parasite power mode) then set 'power' to 1, otherwise the pin will
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
221 // go tri-state at the end of the write to avoid heating in a short or
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
222 // other mishap.
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
223 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
224 void OneWire::write(uint8_t v, uint8_t power /* = 0 */) {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
225 uint8_t bitMask;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
226
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
227 for (bitMask = 0x01; bitMask; bitMask <<= 1) {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
228 OneWire::write_bit( (bitMask & v)?1:0);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
229 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
230 if ( !power) {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
231 noInterrupts();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
232 DIRECT_MODE_INPUT(baseReg, bitmask);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
233 DIRECT_WRITE_LOW(baseReg, bitmask);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
234 interrupts();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
235 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
236 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
237
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
238 void OneWire::write_bytes(const uint8_t *buf, uint16_t count, bool power /* = 0 */) {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
239 for (uint16_t i = 0 ; i < count ; i++)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
240 write(buf[i]);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
241 if (!power) {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
242 noInterrupts();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
243 DIRECT_MODE_INPUT(baseReg, bitmask);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
244 DIRECT_WRITE_LOW(baseReg, bitmask);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
245 interrupts();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
246 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
247 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
248
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
249 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
250 // Read a byte
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
251 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
252 uint8_t OneWire::read() {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
253 uint8_t bitMask;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
254 uint8_t r = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
255
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
256 for (bitMask = 0x01; bitMask; bitMask <<= 1) {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
257 if ( OneWire::read_bit()) r |= bitMask;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
258 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
259 return r;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
260 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
261
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
262 void OneWire::read_bytes(uint8_t *buf, uint16_t count) {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
263 for (uint16_t i = 0 ; i < count ; i++)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
264 buf[i] = read();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
265 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
266
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
267 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
268 // Do a ROM select
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
269 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
270 void OneWire::select(const uint8_t rom[8])
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
271 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
272 uint8_t i;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
273
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
274 write(0x55); // Choose ROM
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
275
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
276 for (i = 0; i < 8; i++) write(rom[i]);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
277 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
278
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
279 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
280 // Do a ROM skip
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
281 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
282 void OneWire::skip()
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
283 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
284 write(0xCC); // Skip ROM
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
285 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
286
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
287 void OneWire::depower()
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
288 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
289 noInterrupts();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
290 DIRECT_MODE_INPUT(baseReg, bitmask);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
291 interrupts();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
292 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
293
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
294 #if ONEWIRE_SEARCH
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
295
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
296 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
297 // You need to use this function to start a search again from the beginning.
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
298 // You do not need to do it for the first search, though you could.
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
299 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
300 void OneWire::reset_search()
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
301 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
302 // reset the search state
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
303 LastDiscrepancy = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
304 LastDeviceFlag = FALSE;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
305 LastFamilyDiscrepancy = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
306 for(int i = 7; ; i--) {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
307 ROM_NO[i] = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
308 if ( i == 0) break;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
309 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
310 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
311
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
312 // Setup the search to find the device type 'family_code' on the next call
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
313 // to search(*newAddr) if it is present.
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
314 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
315 void OneWire::target_search(uint8_t family_code)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
316 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
317 // set the search state to find SearchFamily type devices
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
318 ROM_NO[0] = family_code;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
319 for (uint8_t i = 1; i < 8; i++)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
320 ROM_NO[i] = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
321 LastDiscrepancy = 64;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
322 LastFamilyDiscrepancy = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
323 LastDeviceFlag = FALSE;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
324 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
325
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
326 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
327 // Perform a search. If this function returns a '1' then it has
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
328 // enumerated the next device and you may retrieve the ROM from the
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
329 // OneWire::address variable. If there are no devices, no further
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
330 // devices, or something horrible happens in the middle of the
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
331 // enumeration then a 0 is returned. If a new device is found then
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
332 // its address is copied to newAddr. Use OneWire::reset_search() to
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
333 // start over.
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
334 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
335 // --- Replaced by the one from the Dallas Semiconductor web site ---
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
336 //--------------------------------------------------------------------------
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
337 // Perform the 1-Wire Search Algorithm on the 1-Wire bus using the existing
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
338 // search state.
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
339 // Return TRUE : device found, ROM number in ROM_NO buffer
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
340 // FALSE : device not found, end of search
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
341 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
342 uint8_t OneWire::search(uint8_t *newAddr)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
343 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
344 uint8_t id_bit_number;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
345 uint8_t last_zero, rom_byte_number, search_result;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
346 uint8_t id_bit, cmp_id_bit;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
347
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
348 unsigned char rom_byte_mask, search_direction;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
349
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
350 // initialize for search
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
351 id_bit_number = 1;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
352 last_zero = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
353 rom_byte_number = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
354 rom_byte_mask = 1;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
355 search_result = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
356
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
357 // if the last call was not the last one
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
358 if (!LastDeviceFlag)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
359 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
360 // 1-Wire reset
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
361 if (!reset())
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
362 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
363 // reset the search
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
364 LastDiscrepancy = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
365 LastDeviceFlag = FALSE;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
366 LastFamilyDiscrepancy = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
367 return FALSE;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
368 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
369
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
370 // issue the search command
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
371 write(0xF0);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
372
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
373 // loop to do the search
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
374 do
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
375 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
376 // read a bit and its complement
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
377 id_bit = read_bit();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
378 cmp_id_bit = read_bit();
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
379
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
380 // check for no devices on 1-wire
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
381 if ((id_bit == 1) && (cmp_id_bit == 1))
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
382 break;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
383 else
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
384 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
385 // all devices coupled have 0 or 1
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
386 if (id_bit != cmp_id_bit)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
387 search_direction = id_bit; // bit write value for search
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
388 else
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
389 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
390 // if this discrepancy if before the Last Discrepancy
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
391 // on a previous next then pick the same as last time
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
392 if (id_bit_number < LastDiscrepancy)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
393 search_direction = ((ROM_NO[rom_byte_number] & rom_byte_mask) > 0);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
394 else
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
395 // if equal to last pick 1, if not then pick 0
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
396 search_direction = (id_bit_number == LastDiscrepancy);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
397
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
398 // if 0 was picked then record its position in LastZero
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
399 if (search_direction == 0)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
400 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
401 last_zero = id_bit_number;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
402
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
403 // check for Last discrepancy in family
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
404 if (last_zero < 9)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
405 LastFamilyDiscrepancy = last_zero;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
406 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
407 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
408
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
409 // set or clear the bit in the ROM byte rom_byte_number
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
410 // with mask rom_byte_mask
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
411 if (search_direction == 1)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
412 ROM_NO[rom_byte_number] |= rom_byte_mask;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
413 else
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
414 ROM_NO[rom_byte_number] &= ~rom_byte_mask;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
415
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
416 // serial number search direction write bit
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
417 write_bit(search_direction);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
418
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
419 // increment the byte counter id_bit_number
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
420 // and shift the mask rom_byte_mask
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
421 id_bit_number++;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
422 rom_byte_mask <<= 1;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
423
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
424 // if the mask is 0 then go to new SerialNum byte rom_byte_number and reset mask
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
425 if (rom_byte_mask == 0)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
426 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
427 rom_byte_number++;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
428 rom_byte_mask = 1;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
429 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
430 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
431 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
432 while(rom_byte_number < 8); // loop until through all ROM bytes 0-7
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
433
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
434 // if the search was successful then
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
435 if (!(id_bit_number < 65))
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
436 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
437 // search successful so set LastDiscrepancy,LastDeviceFlag,search_result
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
438 LastDiscrepancy = last_zero;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
439
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
440 // check for last device
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
441 if (LastDiscrepancy == 0)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
442 LastDeviceFlag = TRUE;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
443
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
444 search_result = TRUE;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
445 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
446 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
447
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
448 // if no device found then reset counters so next 'search' will be like a first
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
449 if (!search_result || !ROM_NO[0])
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
450 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
451 LastDiscrepancy = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
452 LastDeviceFlag = FALSE;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
453 LastFamilyDiscrepancy = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
454 search_result = FALSE;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
455 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
456 for (int i = 0; i < 8; i++) newAddr[i] = ROM_NO[i];
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
457 return search_result;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
458 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
459
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
460 #endif
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
461
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
462 #if ONEWIRE_CRC
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
463 // The 1-Wire CRC scheme is described in Maxim Application Note 27:
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
464 // "Understanding and Using Cyclic Redundancy Checks with Maxim iButton Products"
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
465 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
466
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
467 #if ONEWIRE_CRC8_TABLE
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
468 // This table comes from Dallas sample code where it is freely reusable,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
469 // though Copyright (C) 2000 Dallas Semiconductor Corporation
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
470 static const uint8_t PROGMEM dscrc_table[] = {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
471 0, 94,188,226, 97, 63,221,131,194,156,126, 32,163,253, 31, 65,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
472 157,195, 33,127,252,162, 64, 30, 95, 1,227,189, 62, 96,130,220,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
473 35,125,159,193, 66, 28,254,160,225,191, 93, 3,128,222, 60, 98,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
474 190,224, 2, 92,223,129, 99, 61,124, 34,192,158, 29, 67,161,255,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
475 70, 24,250,164, 39,121,155,197,132,218, 56,102,229,187, 89, 7,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
476 219,133,103, 57,186,228, 6, 88, 25, 71,165,251,120, 38,196,154,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
477 101, 59,217,135, 4, 90,184,230,167,249, 27, 69,198,152,122, 36,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
478 248,166, 68, 26,153,199, 37,123, 58,100,134,216, 91, 5,231,185,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
479 140,210, 48,110,237,179, 81, 15, 78, 16,242,172, 47,113,147,205,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
480 17, 79,173,243,112, 46,204,146,211,141,111, 49,178,236, 14, 80,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
481 175,241, 19, 77,206,144,114, 44,109, 51,209,143, 12, 82,176,238,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
482 50,108,142,208, 83, 13,239,177,240,174, 76, 18,145,207, 45,115,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
483 202,148,118, 40,171,245, 23, 73, 8, 86,180,234,105, 55,213,139,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
484 87, 9,235,181, 54,104,138,212,149,203, 41,119,244,170, 72, 22,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
485 233,183, 85, 11,136,214, 52,106, 43,117,151,201, 74, 20,246,168,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
486 116, 42,200,150, 21, 75,169,247,182,232, 10, 84,215,137,107, 53};
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
487
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
488 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
489 // Compute a Dallas Semiconductor 8 bit CRC. These show up in the ROM
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
490 // and the registers. (note: this might better be done without to
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
491 // table, it would probably be smaller and certainly fast enough
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
492 // compared to all those delayMicrosecond() calls. But I got
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
493 // confused, so I use this table from the examples.)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
494 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
495 uint8_t OneWire::crc8(const uint8_t *addr, uint8_t len)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
496 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
497 uint8_t crc = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
498
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
499 while (len--) {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
500 crc = pgm_read_byte(dscrc_table + (crc ^ *addr++));
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
501 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
502 return crc;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
503 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
504 #else
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
505 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
506 // Compute a Dallas Semiconductor 8 bit CRC directly.
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
507 // this is much slower, but much smaller, than the lookup table.
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
508 //
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
509 uint8_t OneWire::crc8(const uint8_t *addr, uint8_t len)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
510 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
511 uint8_t crc = 0;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
512
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
513 while (len--) {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
514 uint8_t inbyte = *addr++;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
515 for (uint8_t i = 8; i; i--) {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
516 uint8_t mix = (crc ^ inbyte) & 0x01;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
517 crc >>= 1;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
518 if (mix) crc ^= 0x8C;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
519 inbyte >>= 1;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
520 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
521 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
522 return crc;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
523 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
524 #endif
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
525
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
526 #if ONEWIRE_CRC16
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
527 bool OneWire::check_crc16(const uint8_t* input, uint16_t len, const uint8_t* inverted_crc, uint16_t crc)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
528 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
529 crc = ~crc16(input, len, crc);
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
530 return (crc & 0xFF) == inverted_crc[0] && (crc >> 8) == inverted_crc[1];
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
531 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
532
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
533 uint16_t OneWire::crc16(const uint8_t* input, uint16_t len, uint16_t crc)
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
534 {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
535 static const uint8_t oddparity[16] =
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
536 { 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0 };
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
537
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
538 for (uint16_t i = 0 ; i < len ; i++) {
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
539 // Even though we're just copying a byte from the input,
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
540 // we'll be doing 16-bit computation with it.
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
541 uint16_t cdata = input[i];
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
542 cdata = (cdata ^ crc) & 0xff;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
543 crc >>= 8;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
544
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
545 if (oddparity[cdata & 0x0F] ^ oddparity[cdata >> 4])
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
546 crc ^= 0xC001;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
547
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
548 cdata <<= 6;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
549 crc ^= cdata;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
550 cdata <<= 1;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
551 crc ^= cdata;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
552 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
553 return crc;
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
554 }
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
555 #endif
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
556
4f5825a9fc47 some external arduino libs, minus examples and docs
drewp <drewp@bigasterisk.com>
parents:
diff changeset
557 #endif