0
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1 /*
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2 * Various 1 wire routines
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3 * Search routine is copied from the Dallas owpd library with mods
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4 * available from here http://www.ibutton.com/software/1wire/wirekit.html
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5 *
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6 * $Id$
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7 *
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8 * Copyright (c) 2004
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9 * Daniel O'Connor <darius@dons.net.au>. All rights reserved.
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10 *
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11 * Redistribution and use in source and binary forms, with or without
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12 * modification, are permitted provided that the following conditions
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13 * are met:
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14 * 1. Redistributions of source code must retain the above copyright
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15 * notice, this list of conditions and the following disclaimer.
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16 * 2. Redistributions in binary form must reproduce the above copyright
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17 * notice, this list of conditions and the following disclaimer in the
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18 * documentation and/or other materials provided with the distribution.
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19 *
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20 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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23 * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
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24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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30 * SUCH DAMAGE.
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31 */
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32
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33 /*
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34 * No user servicable parts inside
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35 *
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36 * Modify 1wire-config.h
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37 */
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38
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39 #include <stdio.h>
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40 #include <avr/io.h>
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41 #include <avr/pgmspace.h>
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42 #include <util/delay.h>
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43 #include "1wire.h"
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44 #include "1wire-config.h"
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45 #include "cons.h"
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46
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47 static uint8_t OW_LastDevice = 0;
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48 static uint8_t OW_LastDiscrepancy = 0;
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49 static uint8_t OW_LastFamilyDiscrepancy = 0;
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50
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51 const PROGMEM char *OWProgROM_Status[] = {
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52 "OK",
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53 "no HW support",
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54 "Invalid params",
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55 "module missing/broken"
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56 };
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57
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58 /*-----------------------------------------------------------------------------
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59 * Configure the IO port as we need
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60 */
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61 void
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62 OWInit(void) {
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63 OWBUSINIT();
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64 OWSETBUSHIGH();
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65 }
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66
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67 /*-----------------------------------------------------------------------------
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68 * Generate a 1-Wire reset, return 0 if presence pulse was found, 1 if it
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69 * wasn't, or 2 if the line appears to be being held low.
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70 *
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71 * (NOTE: Does not handle alarm presence from DS2404/DS1994)
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72 */
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73 uint8_t
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74 OWTouchReset(void) {
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75 OWDELAY_G;
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76
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77 /* Check the bus isn't being held low (ie it's broken) Do it after
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78 * the delay so we guarantee we don't see a slave from a previous
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79 * comms attempt
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80 */
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81 #if 0
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82 OWSETREAD();
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83 if(OWREADBUS() == 0)
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84 return 2;
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85 #endif
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86
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87 OWSETBUSLOW();
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88 OWDELAY_H;
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89 OWSETBUSHIGH();
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90 OWDELAY_I;
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91
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92 OWSETREAD();
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93 return(OWREADBUS());
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94 }
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95
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96 /*-----------------------------------------------------------------------------
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97 * Send a 1-wire write bit.
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98 */
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99 void
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100 OWWriteBit(uint8_t bit) {
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101 OWDELAY_I;
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102
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103 if (bit) {
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104 OWSETBUSLOW();
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105 OWDELAY_A;
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106 OWSETBUSHIGH();
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107 OWDELAY_B;
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108 } else {
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109 OWSETBUSLOW();
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110 OWDELAY_C;
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111 OWSETBUSHIGH();
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112 OWDELAY_D;
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113 }
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114 }
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115
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116 /*-----------------------------------------------------------------------------
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117 * Read a bit from the 1-wire bus and return it.
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118 */
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119 uint8_t
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120 OWReadBit(void) {
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121 OWDELAY_I;
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122
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123 OWSETBUSLOW();
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124 OWDELAY_A;
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125 OWSETBUSHIGH();
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126 OWDELAY_E;
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127 OWSETREAD();
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128 return(OWREADBUS());
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129 }
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130
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131 /*-----------------------------------------------------------------------------
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132 * Write a byte to the 1-wire bus
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133 */
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134 void
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135 OWWriteByte(uint8_t data) {
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136 uint8_t i;
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137
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138 /* Send LSB first */
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139 for (i = 0; i < 8; i++) {
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140 OWWriteBit(data & 0x01);
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141 data >>= 1;
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142 }
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143 }
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144
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145 /*-----------------------------------------------------------------------------
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146 * Read a byte from the 1-wire bus
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147 */
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148 uint8_t
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149 OWReadByte(void) {
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150 int i, result = 0;
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151
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152 for (i = 0; i < 8; i++) {
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153 result >>= 1;
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154 if (OWReadBit())
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155 result |= 0x80;
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156 }
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157 return(result);
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158 }
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159
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160 /*-----------------------------------------------------------------------------
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161 * Write a 1-wire data byte and return the sampled result.
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162 */
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163 uint8_t
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164 OWTouchByte(uint8_t data) {
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165 uint8_t i, result = 0;
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166
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167 for (i = 0; i < 8; i++) {
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168 result >>= 1;
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169
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170 /* If sending a 1 then read a bit, otherwise write a 0 */
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171 if (data & 0x01) {
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172 if (OWReadBit())
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173 result |= 0x80;
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174 } else
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175 OWWriteBit(0);
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176
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177 data >>= 1;
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178 }
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179
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180 return(result);
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181 }
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182
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183 /*-----------------------------------------------------------------------------
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184 * Write a block of bytes to the 1-wire bus and return the sampled result in
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185 * the same buffer
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186 */
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187 void
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188 OWBlock(uint8_t *data, int len) {
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189 int i;
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190
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191 for (i = 0; i < len; i++)
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192 data[i] = OWTouchByte(data[i]);
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193 }
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194
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195
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196 /*-----------------------------------------------------------------------------
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197 * Send a 1 wire command to a device, or all if no ROM ID provided
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198 */
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199 void
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200 OWSendCmd(uint8_t *ROM, uint8_t cmd) {
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201 uint8_t i;
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202
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203 OWTouchReset();
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204
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205 if (ROM == NULL)
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206 OWWriteByte(OW_SKIP_ROM_CMD);
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207 else {
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208 OWWriteByte(OW_MATCH_ROM_CMD);
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209 for (i = 0; i < 8; i++)
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210 OWWriteByte(ROM[i]);
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211 }
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212 OWWriteByte(cmd);
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213 }
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214
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215 /*-----------------------------------------------------------------------------
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216 * Search algorithm from App note 187 (and 162)
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217 *
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218 * OWFirst/OWNext return..
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219 * 1 when something is found,
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220 * 0 no more modules
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221 * -1 if no presence pulse,
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222 * -2 if bad CRC,
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223 * -3 if bad wiring.
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224 */
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225 uint8_t
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226 OWFirst(uint8_t *ROM, uint8_t do_reset, uint8_t alarm_only) {
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227 /* Reset state */
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228 OW_LastDiscrepancy = 0;
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229 OW_LastDevice = 0;
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230 OW_LastFamilyDiscrepancy = 0;
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231
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232 /* Go looking */
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233 return (OWNext(ROM, do_reset, alarm_only));
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234 }
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235
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236 /* Returns 1 when something is found, 0 if nothing left */
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237 uint8_t
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238 OWNext(uint8_t *ROM, uint8_t do_reset, uint8_t alarm_only) {
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239 uint8_t bit_test, search_direction, bit_number;
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240 uint8_t last_zero, rom_byte_number, rom_byte_mask;
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241 uint8_t lastcrc8, crcaccum;
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242 int8_t next_result;
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243
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244 /* Init for search */
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245 bit_number = 1;
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246 last_zero = 0;
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247 rom_byte_number = 0;
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248 rom_byte_mask = 1;
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249 next_result = OW_NOMODULES;
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250 lastcrc8 = 0;
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251 crcaccum = 0;
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252
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253 /* if the last call was not the last one */
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254 if (!OW_LastDevice) {
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255 /* check if reset first is requested */
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256 if (do_reset) {
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257 /* reset the 1-wire
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258 * if there are no parts on 1-wire, return 0 */
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259 OWPUTSP(PSTR("Resetting\r\n"));
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260 switch (OWTouchReset()) {
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261 case 0:
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262 break;
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263
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264 case 1:
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265 /* reset the search */
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266 OW_LastDiscrepancy = 0;
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267 OW_LastFamilyDiscrepancy = 0;
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268 OWPUTSP(PSTR("No devices on bus\r\n"));
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269 return OW_NOPRESENCE;
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270 break;
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271
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272 case 2:
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273 /* reset the search */
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274 OW_LastDiscrepancy = 0;
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275 OW_LastFamilyDiscrepancy = 0;
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276 OWPUTSP(PSTR("Bus appears to be being held low\r\n"));
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277 return OW_BADWIRE;
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278 break;
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279
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280 }
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281 }
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282
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283 /* If finding alarming devices issue a different command */
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284 if (alarm_only)
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285 OWWriteByte(OW_SEARCH_ALRM_CMD); /* issue the alarming search command */
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286 else
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287 OWWriteByte(OW_SEARCH_ROM_CMD); /* issue the search command */
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288
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289 /* pause before beginning the search */
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290 OWDELAY_I;
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291 OWDELAY_I;
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292 OWDELAY_I;
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293
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294 /* loop to do the search */
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295 do {
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296 /* read a bit and its compliment */
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297 bit_test = OWReadBit() << 1;
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298 bit_test |= OWReadBit();
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299
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300 OWPRINTFP(PSTR("bit_test = %d\r\n"), bit_test);
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301
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302 /* check for no devices on 1-wire */
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303 if (bit_test == 3) {
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304 OWPRINTFP(PSTR("bit_test = %d\r\n"), bit_test);
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305 return(OW_BADWIRE);
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306 }
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307 else {
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308 /* all devices coupled have 0 or 1 */
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309 if (bit_test > 0)
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310 search_direction = !(bit_test & 0x01); /* bit write value for search */
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311 else {
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312 /* if this discrepancy is before the Last Discrepancy
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313 * on a previous OWNext then pick the same as last time */
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314 if (bit_number < OW_LastDiscrepancy)
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315 search_direction = ((ROM[rom_byte_number] & rom_byte_mask) > 0);
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316 else
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317 /* if equal to last pick 1, if not then pick 0 */
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318 search_direction = (bit_number == OW_LastDiscrepancy);
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319
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320 /* if 0 was picked then record its position in LastZero */
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321 if (search_direction == 0) {
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322 last_zero = bit_number;
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323
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324 /* check for Last discrepancy in family */
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325 if (last_zero < 9)
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326 OW_LastFamilyDiscrepancy = last_zero;
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327 }
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328 }
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329
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330 /* set or clear the bit in the ROM byte rom_byte_number
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331 * with mask rom_byte_mask */
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332 if (search_direction == 1)
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333 ROM[rom_byte_number] |= rom_byte_mask;
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334 else
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335 ROM[rom_byte_number] &= ~rom_byte_mask;
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336
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337 /* serial number search direction write bit */
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338 OWWriteBit(search_direction);
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339
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340 /* increment the byte counter bit_number
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341 * and shift the mask rom_byte_mask */
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342 bit_number++;
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343 rom_byte_mask <<= 1;
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344
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345 /* if the mask is 0 then go to new ROM byte rom_byte_number
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346 * and reset mask */
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347 if (rom_byte_mask == 0) {
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348 OWCRC(ROM[rom_byte_number], &crcaccum); /* accumulate the CRC */
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349 lastcrc8 = crcaccum;
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350
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351 rom_byte_number++;
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352 rom_byte_mask = 1;
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353 }
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354 }
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355 } while (rom_byte_number < 8); /* loop until through all ROM bytes 0-7 */
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356
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357 /* if the search was successful then */
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358 if (!(bit_number < 65) || lastcrc8) {
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359 if (lastcrc8) {
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360 OWPRINTFP(PSTR("Bad CRC (%d)\r\n"), lastcrc8);
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361 next_result = OW_BADCRC;
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362 } else {
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363 /* search successful so set LastDiscrepancy,LastDevice,next_result */
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364 OW_LastDiscrepancy = last_zero;
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365 OW_LastDevice = (OW_LastDiscrepancy == 0);
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366 OWPRINTFP(PSTR("Last device = %d\r\n"), OW_LastDevice);
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367 next_result = OW_FOUND;
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368 }
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369 }
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370 }
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371
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372 /* if no device found then reset counters so next 'next' will be
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373 * like a first */
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374 if (next_result != OW_FOUND || ROM[0] == 0) {
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375 OW_LastDiscrepancy = 0;
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376 OW_LastDevice = 0;
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377 OW_LastFamilyDiscrepancy = 0;
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378 }
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379
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380 if (next_result == OW_FOUND && ROM[0] == 0x00)
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381 next_result = OW_BADWIRE;
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382
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383 return next_result;
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384
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385 }
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386
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387 uint8_t PROGMEM dscrc_table[] = {
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388 0, 94, 188, 226, 97, 63, 221, 131, 194, 156, 126, 32, 163, 253, 31, 65,
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389 157, 195, 33, 127, 252, 162, 64, 30, 95, 1, 227, 189, 62, 96, 130, 220,
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390 35, 125, 159, 193, 66, 28, 254, 160, 225, 191, 93, 3, 128, 222, 60, 98,
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391 190, 224, 2, 92, 223, 129, 99, 61, 124, 34, 192, 158, 29, 67, 161, 255,
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392 70, 24, 250, 164, 39, 121, 155, 197, 132, 218, 56, 102, 229, 187, 89, 7,
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393 219, 133,103, 57, 186, 228, 6, 88, 25, 71, 165, 251, 120, 38, 196, 154,
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394 101, 59, 217, 135, 4, 90, 184, 230, 167, 249, 27, 69, 198, 152, 122, 36,
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395 248, 166, 68, 26, 153, 199, 37, 123, 58, 100, 134, 216, 91, 5, 231, 185,
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396 140,210, 48, 110, 237, 179, 81, 15, 78, 16, 242, 172, 47, 113,147, 205,
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397 17, 79, 173, 243, 112, 46, 204, 146, 211,141, 111, 49, 178, 236, 14, 80,
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398 175, 241, 19, 77, 206, 144, 114, 44, 109, 51, 209, 143, 12, 82,176, 238,
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399 50, 108, 142, 208, 83, 13, 239, 177, 240, 174, 76, 18, 145, 207, 45, 115,
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400 202, 148, 118, 40, 171, 245, 23, 73, 8, 86, 180, 234, 105, 55, 213, 139,
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401 87, 9, 235, 181, 54, 104, 138, 212, 149, 203, 41, 119, 244, 170, 72, 22,
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402 233, 183, 85, 11, 136, 214, 52, 106, 43, 117, 151, 201, 74, 20, 246, 168,
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403 116, 42, 200, 150, 21, 75, 169, 247, 182, 232, 10, 84, 215, 137, 107, 53
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404 };
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405
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406 /*-----------------------------------------------------------------------------
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407 * Update *crc based on the value of x
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408 */
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409 void
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410 OWCRC(uint8_t x, uint8_t *crc) {
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411 *crc = pgm_read_byte(&dscrc_table[(*crc) ^ x]);
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412 }
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413
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414 /*-----------------------------------------------------------------------------
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415 * Program a DS2502's memory
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416 *
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417 * Arguments
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418 * ROM - ROM ID (or NULL to send SKIP_ROM)
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419 * start - Start address (bytes)
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420 * len - Length of data to write
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421 * data - Data to write
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422 * exact - If true, only accept exact matches for programming,
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423 * otherwise only ensure the bits we requested were
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424 * programmed [to 0]
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425 * status - If true program status rather than memory
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426 *
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427 * Returns..
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428 * 0 if all is OK
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429 * 1 if the programming is not possible
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430 * 2 if the parameters were invalid
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431 * 3 if the DS2502 didn't respond appropriately (also happens if the
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432 * module doesn't exist)
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433 */
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434 uint8_t
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435 OWProgROM(uint8_t *ROM, uint8_t start, uint8_t len, uint8_t *data, uint8_t exact, uint8_t status) {
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436 #if defined(OWSETVPPON) && defined(OWSETVPPOFF)
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437 uint8_t crc, i, tmp;
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438
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439 /* Stupid programmer detection */
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440 if (status) {
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441 if (start + len > 3)
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442 return(2);
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443 } else {
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444 if (start + len > 127)
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445 return(2);
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446 }
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447
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448 if (len < 1)
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449 return(2);
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450
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451 OWDELAY_I;
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452 if (OWTouchReset() != 0) {
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453 cons_putsP(PSTR("No presence pulse\r\n"));
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454 return(3);
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455 }
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456
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457 crc = 0;
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458
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459 /* Send the command */
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460 if (status) {
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461 OWSendCmd(ROM, OW_WRITE_STATUS);
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462 OWCRC(OW_WRITE_STATUS, &crc);
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463 } else {
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464 OWSendCmd(ROM, OW_WRITE_MEMORY);
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465 OWCRC(OW_WRITE_MEMORY, &crc);
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466 }
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467
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468 /* And the start address
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469 * (2 bytes even though one would do)
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470 */
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471 OWWriteByte(start);
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472 OWCRC(start, &crc);
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473
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474 OWWriteByte(0x00);
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475 OWCRC(0x00, &crc);
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476
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477 for (i = 0; i < len; i++) {
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478 cons_putsP(PSTR("Programming "));
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479 cons_puts_hex(data[i]);
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480 cons_putsP(PSTR(" to "));
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481 cons_puts_hex(start + i);
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482 cons_putsP(PSTR("\r\n"));
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483
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484 OWWriteByte(data[i]);
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485 OWCRC(data[i], &crc);
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486
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487 tmp = OWReadByte();
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488
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489 if (crc != tmp) {
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490 cons_putsP(PSTR("CRC mismatch "));
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491 cons_puts_hex(crc);
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492 cons_putsP(PSTR(" vs "));
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|
493 cons_puts_hex(tmp);
|
|
494 cons_putsP(PSTR("\r\n"));
|
|
495
|
|
496 OWTouchReset();
|
|
497 return(3);
|
|
498 }
|
|
499
|
|
500 OWSETVPPON();
|
|
501 OWDELAY_H;
|
|
502 OWSETVPPOFF();
|
|
503
|
|
504 tmp = OWReadByte();
|
|
505
|
|
506 /* Check the bits we turned off are off */
|
|
507 /*
|
|
508 for (i = 0; i < 8; i++)
|
|
509 if (!(data[i] & 1 << i) && (tmp & 1 << i))
|
|
510 return(-3);
|
|
511 */
|
|
512 if ((!data[i] & tmp) != 0) {
|
|
513 cons_putsP(PSTR("Readback mismatch "));
|
|
514 cons_puts_hex(data[i]);
|
|
515 cons_putsP(PSTR(" vs "));
|
|
516 cons_puts_hex(data[i]);
|
|
517 cons_putsP(PSTR("\r\n"));
|
|
518
|
|
519 OWTouchReset();
|
|
520 return(3);
|
|
521 }
|
|
522
|
|
523 /* The DS2502 loads it's CRC register with the address of the
|
|
524 * next byte */
|
|
525 crc = 0;
|
|
526 OWCRC(start + i + 1, &crc);
|
|
527 }
|
|
528
|
|
529 return(0);
|
|
530 #else
|
|
531 return(1);
|
|
532 #endif
|
|
533 }
|
|
534
|
|
535 /*
|
|
536 * OWGetTemp
|
|
537 *
|
|
538 * Get the temperature from a 1wire bus module
|
|
539 *
|
|
540 * Returns temperature in hundredths of a degree or OW_TEMP_xxx on
|
|
541 * error.
|
|
542 */
|
|
543 int16_t
|
|
544 OWGetTemp(uint8_t *ROM) {
|
|
545 int8_t i;
|
|
546 uint8_t crc, buf[9];
|
|
547 int16_t temp;
|
|
548 int16_t tfrac;
|
|
549
|
|
550 if (ROM[0] != OW_FAMILY_TEMP)
|
|
551 return OW_TEMP_WRONG_FAM;
|
|
552
|
|
553 OWSendCmd(ROM, OW_CONVERTT_CMD);
|
|
554
|
|
555 i = 0;
|
|
556
|
|
557 /* Wait for the conversion */
|
|
558 while (OWReadBit() == 0)
|
|
559 i = 1;
|
|
560
|
|
561 /* Check that we talked to a module and it did something */
|
|
562 if (i == 0) {
|
|
563 return OW_TEMP_NO_ROM;
|
|
564 }
|
|
565
|
|
566 OWSendCmd(ROM, OW_RD_SCR_CMD);
|
|
567 crc = 0;
|
|
568 for (i = 0; i < 8; i++) {
|
|
569 buf[i] = OWReadByte();
|
|
570 OWCRC(buf[i], &crc);
|
|
571 }
|
|
572 buf[i] = OWReadByte();
|
|
573 if (crc != buf[8])
|
|
574 return OW_TEMP_CRC_ERR;
|
|
575 temp = buf[0];
|
|
576 if (buf[1] & 0x80)
|
|
577 temp -= 256;
|
|
578
|
|
579 /* Chop off 0.5 degree bit */
|
|
580 temp >>= 1;
|
|
581
|
|
582 /* Calulate the fractional remainder */
|
|
583 tfrac = buf[7] - buf[6];
|
|
584
|
|
585 /* Work in 100'th of degreess to save on floats */
|
|
586 tfrac *= (int16_t)100;
|
|
587
|
|
588 /* Divide by count */
|
|
589 tfrac /= buf[7];
|
|
590
|
|
591 /* Subtract 0.25 deg from temp */
|
|
592 tfrac += 75;
|
|
593 if (tfrac < 100)
|
|
594 temp--;
|
|
595 else
|
|
596 tfrac -= 100;
|
|
597
|
|
598 i = temp;
|
|
599 temp *= 100;
|
|
600 temp += tfrac;
|
|
601
|
|
602 return(temp);
|
|
603 }
|
|
604
|
|
605 /*
|
|
606 * OWTempStatusStr
|
|
607 *
|
|
608 * Return a string for each OW_TEMP_xxx error code
|
|
609 *
|
|
610 * shrt = 1 returns short strings
|
|
611 *
|
|
612 */
|
|
613 const char *
|
|
614 OWTempStatusStr(int16_t val, uint8_t shrt) {
|
|
615 if (val > OW_TEMP_BADVAL) {
|
|
616 if (shrt)
|
|
617 return PSTR("OK");
|
|
618 else
|
|
619 return PSTR("OK");
|
|
620 }
|
|
621
|
|
622 switch (val) {
|
|
623 case OW_TEMP_WRONG_FAM:
|
|
624 if (shrt)
|
|
625 return PSTR("WrFam");
|
|
626 else
|
|
627 return PSTR("Wrong family");
|
|
628 break;
|
|
629 case OW_TEMP_CRC_ERR:
|
|
630 if (shrt)
|
|
631 return PSTR("CRCErr");
|
|
632 else
|
|
633 return PSTR("CRC Error");
|
|
634 break;
|
|
635 case OW_TEMP_NO_ROM:
|
|
636 if (shrt)
|
|
637 return PSTR("NoROM");
|
|
638 else
|
|
639 return PSTR("ROM did not reply");
|
|
640 break;
|
|
641 default:
|
|
642 if (shrt)
|
|
643 return PSTR("???");
|
|
644 else
|
|
645 return PSTR("Unknown error code");
|
|
646 break;
|
|
647 }
|
|
648 }
|