annotate 1wire.c @ 60:50fca9562310

Add support for reading/writing to a DS1307 over TWI/IIC. Note that iic_read() appears to have a bug where it stops 1 byte earlier than expected, work around it for now by adding 1 in the gettod() function. tempctrl.c now prints the TOD as read from the RTC for each line.
author darius@Inchoate
date Thu, 30 Oct 2008 11:53:32 +1030
parents efd44dc40934
children
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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 "not possible (no HW support)",
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54 "Invalid parameters",
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55 "module doesn't exist or didn't respond properly"
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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(OWREADBUS() == 0)
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82 return 2;
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83
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84 OWSETBUSLOW();
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85 OWDELAY_H;
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86 OWSETBUSHIGH();
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87 OWDELAY_I;
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88
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89 return(OWREADBUS());
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90 }
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91
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92 /*-----------------------------------------------------------------------------
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93 * Send a 1-wire write bit.
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94 */
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95 void
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96 OWWriteBit(uint8_t bit) {
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97 OWDELAY_I;
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98
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99 if (bit) {
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100 OWSETBUSLOW();
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101 OWDELAY_A;
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102 OWSETBUSHIGH();
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103 OWDELAY_B;
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104 } else {
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105 OWSETBUSLOW();
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106 OWDELAY_C;
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107 OWSETBUSHIGH();
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108 OWDELAY_D;
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109 }
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110 }
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111
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112 /*-----------------------------------------------------------------------------
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113 * Read a bit from the 1-wire bus and return it.
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114 */
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115 uint8_t
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116 OWReadBit(void) {
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117 OWDELAY_I;
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118
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119 OWSETBUSLOW();
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120 OWDELAY_A;
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121 OWSETBUSHIGH();
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122 OWDELAY_E;
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123 return(OWREADBUS());
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124 }
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125
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126 /*-----------------------------------------------------------------------------
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127 * Write a byte to the 1-wire bus
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128 */
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129 void
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130 OWWriteByte(uint8_t data) {
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131 uint8_t i;
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132
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133 /* Send LSB first */
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134 for (i = 0; i < 8; i++) {
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135 OWWriteBit(data & 0x01);
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136 data >>= 1;
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137 }
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138 }
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139
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140 /*-----------------------------------------------------------------------------
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141 * Read a byte from the 1-wire bus
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142 */
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143 uint8_t
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144 OWReadByte(void) {
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145 int i, result = 0;
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146
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147 for (i = 0; i < 8; i++) {
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148 result >>= 1;
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149 if (OWReadBit())
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150 result |= 0x80;
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151 }
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152 return(result);
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153 }
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154
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155 /*-----------------------------------------------------------------------------
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156 * Write a 1-wire data byte and return the sampled result.
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157 */
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158 uint8_t
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159 OWTouchByte(uint8_t data) {
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160 uint8_t i, result = 0;
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161
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162 for (i = 0; i < 8; i++) {
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163 result >>= 1;
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164
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165 /* If sending a 1 then read a bit, otherwise write a 0 */
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166 if (data & 0x01) {
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167 if (OWReadBit())
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168 result |= 0x80;
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169 } else
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170 OWWriteBit(0);
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171
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172 data >>= 1;
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173 }
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174
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175 return(result);
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176 }
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177
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178 /*-----------------------------------------------------------------------------
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179 * Write a block of bytes to the 1-wire bus and return the sampled result in
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180 * the same buffer
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181 */
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182 void
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183 OWBlock(uint8_t *data, int len) {
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184 int i;
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185
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186 for (i = 0; i < len; i++)
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187 data[i] = OWTouchByte(data[i]);
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188 }
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189
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190
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191 /*-----------------------------------------------------------------------------
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192 * Send a 1 wire command to a device, or all if no ROM ID provided
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193 */
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194 void
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195 OWSendCmd(uint8_t *ROM, uint8_t cmd) {
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196 uint8_t i;
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197
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198 OWTouchReset();
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199
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200 if (ROM == NULL)
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201 OWWriteByte(OW_SKIP_ROM_CMD);
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202 else {
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203 OWWriteByte(OW_MATCH_ROM_CMD);
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204 for (i = 0; i < 8; i++)
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205 OWWriteByte(ROM[i]);
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206 }
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207 OWWriteByte(cmd);
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208 }
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209
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210 /*-----------------------------------------------------------------------------
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211 * Search algorithm from App note 187 (and 162)
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212 *
10
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213 * OWFirst/OWNext return..
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214 * 1 when something is found,
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215 * 0 no more modules
16
026dc24d85e0 Spell presence correctly.
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216 * -1 if no presence pulse,
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217 * -2 if bad CRC,
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218 * -3 if bad wiring.
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219 */
12
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220 uint8_t
0
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221 OWFirst(uint8_t *ROM, uint8_t do_reset, uint8_t alarm_only) {
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222 /* Reset state */
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223 OW_LastDiscrepancy = 0;
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224 OW_LastDevice = 0;
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225 OW_LastFamilyDiscrepancy = 0;
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226
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227 /* Go looking */
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228 return (OWNext(ROM, do_reset, alarm_only));
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229 }
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230
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231 /* Returns 1 when something is found, 0 if nothing left */
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232 uint8_t
0
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233 OWNext(uint8_t *ROM, uint8_t do_reset, uint8_t alarm_only) {
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234 uint8_t bit_test, search_direction, bit_number;
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235 uint8_t last_zero, rom_byte_number, rom_byte_mask;
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236 uint8_t lastcrc8, crcaccum;
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237 int8_t next_result;
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238
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239 /* Init for search */
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240 bit_number = 1;
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241 last_zero = 0;
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242 rom_byte_number = 0;
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243 rom_byte_mask = 1;
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244 next_result = OW_NOMODULES;
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245 lastcrc8 = 0;
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246 crcaccum = 0;
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247
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248 /* if the last call was not the last one */
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249 if (!OW_LastDevice) {
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250 /* check if reset first is requested */
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251 if (do_reset) {
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252 /* reset the 1-wire
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253 * if there are no parts on 1-wire, return 0 */
41
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254 OWPUTSP(PSTR("Resetting\r\n"));
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255 switch (OWTouchReset()) {
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256 case 0:
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257 break;
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258
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259 case 1:
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260 /* reset the search */
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261 OW_LastDiscrepancy = 0;
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262 OW_LastFamilyDiscrepancy = 0;
41
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263 OWPUTSP(PSTR("No devices on bus\r\n"));
22
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264 return OW_NOPRESENCE;
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265 break;
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266
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267 case 2:
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268 /* reset the search */
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269 OW_LastDiscrepancy = 0;
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270 OW_LastFamilyDiscrepancy = 0;
41
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271 OWPUTSP(PSTR("Bus appears to be being held low\r\n"));
22
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272 return OW_BADWIRE;
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273 break;
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274
21
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275 }
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276 }
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277
21
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278 /* If finding alarming devices issue a different command */
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279 if (alarm_only)
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280 OWWriteByte(OW_SEARCH_ALRM_CMD); /* issue the alarming search command */
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281 else
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282 OWWriteByte(OW_SEARCH_ROM_CMD); /* issue the search command */
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283
21
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284 /* pause before beginning the search */
32
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285 OWDELAY_I;
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286 OWDELAY_I;
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287 OWDELAY_I;
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288
21
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289 /* loop to do the search */
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290 do {
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291 /* read a bit and its compliment */
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292 bit_test = OWReadBit() << 1;
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293 bit_test |= OWReadBit();
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294
41
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295 OWPRINTFP(PSTR("bit_test = %d\r\n"), bit_test);
0
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296
21
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297 /* check for no devices on 1-wire */
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298 if (bit_test == 3) {
41
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299 OWPRINTFP(PSTR("bit_test = %d\r\n"), bit_test);
21
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300 return(OW_BADWIRE);
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301 }
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302 else {
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303 /* all devices coupled have 0 or 1 */
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304 if (bit_test > 0)
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305 search_direction = !(bit_test & 0x01); /* bit write value for search */
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306 else {
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307 /* if this discrepancy is before the Last Discrepancy
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308 * on a previous OWNext then pick the same as last time */
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309 if (bit_number < OW_LastDiscrepancy)
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310 search_direction = ((ROM[rom_byte_number] & rom_byte_mask) > 0);
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311 else
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312 /* if equal to last pick 1, if not then pick 0 */
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313 search_direction = (bit_number == OW_LastDiscrepancy);
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314
21
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315 /* if 0 was picked then record its position in LastZero */
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316 if (search_direction == 0) {
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317 last_zero = bit_number;
0
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318
21
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319 /* check for Last discrepancy in family */
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320 if (last_zero < 9)
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321 OW_LastFamilyDiscrepancy = last_zero;
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322 }
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323 }
0
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324
21
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325 /* set or clear the bit in the ROM byte rom_byte_number
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326 * with mask rom_byte_mask */
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327 if (search_direction == 1)
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328 ROM[rom_byte_number] |= rom_byte_mask;
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329 else
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330 ROM[rom_byte_number] &= ~rom_byte_mask;
0
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331
21
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332 /* serial number search direction write bit */
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333 OWWriteBit(search_direction);
0
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334
21
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335 /* increment the byte counter bit_number
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336 * and shift the mask rom_byte_mask */
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337 bit_number++;
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338 rom_byte_mask <<= 1;
0
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339
21
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diff changeset
340 /* if the mask is 0 then go to new ROM byte rom_byte_number
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diff changeset
341 * and reset mask */
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parents: 16
diff changeset
342 if (rom_byte_mask == 0) {
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343 OWCRC(ROM[rom_byte_number], &crcaccum); /* accumulate the CRC */
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344 lastcrc8 = crcaccum;
0
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345
21
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diff changeset
346 rom_byte_number++;
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diff changeset
347 rom_byte_mask = 1;
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diff changeset
348 }
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349 }
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350 } while (rom_byte_number < 8); /* loop until through all ROM bytes 0-7 */
0
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351
21
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diff changeset
352 /* if the search was successful then */
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parents: 16
diff changeset
353 if (!(bit_number < 65) || lastcrc8) {
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parents: 16
diff changeset
354 if (lastcrc8) {
41
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
355 OWPRINTFP(PSTR("Bad CRC (%d)\r\n"), lastcrc8);
21
e82d15fa9a1a Re-format the code.
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parents: 16
diff changeset
356 next_result = OW_BADCRC;
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parents: 16
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357 } else {
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parents: 16
diff changeset
358 /* search successful so set LastDiscrepancy,LastDevice,next_result */
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parents: 16
diff changeset
359 OW_LastDiscrepancy = last_zero;
e82d15fa9a1a Re-format the code.
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parents: 16
diff changeset
360 OW_LastDevice = (OW_LastDiscrepancy == 0);
41
5898fba6593c Add temperature control.
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parents: 33
diff changeset
361 OWPRINTFP(PSTR("Last device = %d\r\n"), OW_LastDevice);
21
e82d15fa9a1a Re-format the code.
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parents: 16
diff changeset
362 next_result = OW_FOUND;
e82d15fa9a1a Re-format the code.
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parents: 16
diff changeset
363 }
e82d15fa9a1a Re-format the code.
darius
parents: 16
diff changeset
364 }
e82d15fa9a1a Re-format the code.
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parents: 16
diff changeset
365 }
0
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366
21
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parents: 16
diff changeset
367 /* if no device found then reset counters so next 'next' will be
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darius
parents: 16
diff changeset
368 * like a first */
e82d15fa9a1a Re-format the code.
darius
parents: 16
diff changeset
369 if (next_result != OW_FOUND || ROM[0] == 0) {
e82d15fa9a1a Re-format the code.
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parents: 16
diff changeset
370 OW_LastDiscrepancy = 0;
e82d15fa9a1a Re-format the code.
darius
parents: 16
diff changeset
371 OW_LastDevice = 0;
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darius
parents: 16
diff changeset
372 OW_LastFamilyDiscrepancy = 0;
e82d15fa9a1a Re-format the code.
darius
parents: 16
diff changeset
373 }
0
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parents:
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374
21
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parents: 16
diff changeset
375 if (next_result == OW_FOUND && ROM[0] == 0x00)
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parents: 16
diff changeset
376 next_result = OW_BADWIRE;
10
eb1faf51968e - Add some useful return values to search functions.
darius
parents: 8
diff changeset
377
21
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parents: 16
diff changeset
378 return next_result;
0
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parents:
diff changeset
379
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parents:
diff changeset
380 }
ffeab3c04e83 Initial revision
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parents:
diff changeset
381
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parents:
diff changeset
382 uint8_t PROGMEM dscrc_table[] = {
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
383 0, 94, 188, 226, 97, 63, 221, 131, 194, 156, 126, 32, 163, 253, 31, 65,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
384 157, 195, 33, 127, 252, 162, 64, 30, 95, 1, 227, 189, 62, 96, 130, 220,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
385 35, 125, 159, 193, 66, 28, 254, 160, 225, 191, 93, 3, 128, 222, 60, 98,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
386 190, 224, 2, 92, 223, 129, 99, 61, 124, 34, 192, 158, 29, 67, 161, 255,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
387 70, 24, 250, 164, 39, 121, 155, 197, 132, 218, 56, 102, 229, 187, 89, 7,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
388 219, 133,103, 57, 186, 228, 6, 88, 25, 71, 165, 251, 120, 38, 196, 154,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
389 101, 59, 217, 135, 4, 90, 184, 230, 167, 249, 27, 69, 198, 152, 122, 36,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
390 248, 166, 68, 26, 153, 199, 37, 123, 58, 100, 134, 216, 91, 5, 231, 185,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
391 140,210, 48, 110, 237, 179, 81, 15, 78, 16, 242, 172, 47, 113,147, 205,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
392 17, 79, 173, 243, 112, 46, 204, 146, 211,141, 111, 49, 178, 236, 14, 80,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
393 175, 241, 19, 77, 206, 144, 114, 44, 109, 51, 209, 143, 12, 82,176, 238,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
394 50, 108, 142, 208, 83, 13, 239, 177, 240, 174, 76, 18, 145, 207, 45, 115,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
395 202, 148, 118, 40, 171, 245, 23, 73, 8, 86, 180, 234, 105, 55, 213, 139,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
396 87, 9, 235, 181, 54, 104, 138, 212, 149, 203, 41, 119, 244, 170, 72, 22,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
397 233, 183, 85, 11, 136, 214, 52, 106, 43, 117, 151, 201, 74, 20, 246, 168,
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
398 116, 42, 200, 150, 21, 75, 169, 247, 182, 232, 10, 84, 215, 137, 107, 53
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
399 };
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
400
33
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
401 /*-----------------------------------------------------------------------------
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
402 * Update *crc based on the value of x
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
403 */
0
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
404 void
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
405 OWCRC(uint8_t x, uint8_t *crc) {
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
406 *crc = pgm_read_byte(&dscrc_table[(*crc) ^ x]);
ffeab3c04e83 Initial revision
darius
parents:
diff changeset
407 }
33
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
408
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
409 /*-----------------------------------------------------------------------------
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
410 * Program a DS2502's memory
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
411 *
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
412 * Arguments
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
413 * ROM - ROM ID (or NULL to send SKIP_ROM)
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
414 * start - Start address (bytes)
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
415 * len - Length of data to write
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
416 * data - Data to write
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
417 * exact - If true, only accept exact matches for programming,
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
418 * otherwise only ensure the bits we requested were
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
419 * programmed [to 0]
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
420 * status - If true program status rather than memory
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
421 *
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
422 * Returns..
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
423 * 0 if all is OK
45
efd44dc40934 Add macros for number system used for temperatures.
darius@Inchoate
parents: 41
diff changeset
424 * 1 if the programming is not possible
33
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
425 * 2 if the parameters were invalid
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
426 * 3 if the DS2502 didn't respond appropriately (also happens if the
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
427 * module doesn't exist)
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
428 */
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
429 uint8_t
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
430 OWProgROM(uint8_t *ROM, uint8_t start, uint8_t len, uint8_t *data, uint8_t exact, uint8_t status) {
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
431 #if defined(OWSETVPPON) && defined(OWSETVPPOFF)
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
432 uint8_t crc, i, tmp;
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
433
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
434 /* Stupid programmer detection */
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
435 if (status) {
45
efd44dc40934 Add macros for number system used for temperatures.
darius@Inchoate
parents: 41
diff changeset
436 if (start + len > 3)
33
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
437 return(2);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
438 } else {
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
439 if (start + len > 127)
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
440 return(2);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
441 }
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
442
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
443 if (len < 1)
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
444 return(2);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
445
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
446 OWDELAY_I;
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
447 if (OWTouchReset() != 0) {
41
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
448 cons_putsP(PSTR("No presence pulse\r\n"));
33
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
449 return(3);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
450 }
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
451
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
452 crc = 0;
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
453
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
454 /* Send the command */
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
455 if (status) {
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
456 OWSendCmd(ROM, OW_WRITE_STATUS);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
457 OWCRC(OW_WRITE_STATUS, &crc);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
458 } else {
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
459 OWSendCmd(ROM, OW_WRITE_MEMORY);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
460 OWCRC(OW_WRITE_MEMORY, &crc);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
461 }
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
462
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
463 /* And the start address
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
464 * (2 bytes even though one would do)
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
465 */
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
466 OWWriteByte(start);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
467 OWCRC(start, &crc);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
468
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
469 OWWriteByte(0x00);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
470 OWCRC(0x00, &crc);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
471
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
472 for (i = 0; i < len; i++) {
41
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
473 cons_putsP(PSTR("Programming "));
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
474 cons_puts_hex(data[i]);
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
475 cons_putsP(PSTR(" to "));
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
476 cons_puts_hex(start + i);
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
477 cons_putsP(PSTR("\r\n"));
33
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
478
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
479 OWWriteByte(data[i]);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
480 OWCRC(data[i], &crc);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
481
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
482 tmp = OWReadByte();
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
483
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
484 if (crc != tmp) {
41
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
485 cons_putsP(PSTR("CRC mismatch "));
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
486 cons_puts_hex(crc);
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
487 cons_putsP(PSTR(" vs "));
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
488 cons_puts_hex(tmp);
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
489 cons_putsP(PSTR("\r\n"));
33
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
490
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
491 OWTouchReset();
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
492 return(3);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
493 }
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
494
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
495 OWSETVPPON();
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
496 OWDELAY_H;
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
497 OWSETVPPOFF();
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
498
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
499 tmp = OWReadByte();
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
500
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
501 /* Check the bits we turned off are off */
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
502 /*
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
503 for (i = 0; i < 8; i++)
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
504 if (!(data[i] & 1 << i) && (tmp & 1 << i))
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
505 return(-3);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
506 */
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
507 if ((!data[i] & tmp) != 0) {
41
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
508 cons_putsP(PSTR("Readback mismatch "));
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
509 cons_puts_hex(data[i]);
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
510 cons_putsP(PSTR(" vs "));
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
511 cons_puts_hex(data[i]);
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
512 cons_putsP(PSTR("\r\n"));
33
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
513
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
514 OWTouchReset();
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
515 return(3);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
516 }
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
517
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
518 /* The DS2502 loads it's CRC register with the address of the
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
519 * next byte */
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
520 crc = 0;
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
521 OWCRC(start + i + 1, &crc);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
522 }
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
523
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
524 return(0);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
525 #else
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
526 return(1);
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
527 #endif
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
528 }
0aa6bf4b98ae - Don't wrap individual debug statements in ifdef, use a conditionally
darius
parents: 32
diff changeset
529
41
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
530 /*
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
531 * OWGetTemp
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
532 *
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
533 * Get the temperature from a 1wire bus module
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
534 *
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
535 * Returns temperature in hundredths of a degree or OW_TEMP_xxx on
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
536 * error.
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
537 */
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
538 int16_t
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
539 OWGetTemp(uint8_t *ROM) {
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
540 int8_t i;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
541 uint8_t crc, buf[9];
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
542 int16_t temp;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
543 int16_t tfrac;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
544
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
545 if (ROM[0] != OW_FAMILY_TEMP)
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
546 return OW_TEMP_WRONG_FAM;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
547
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
548 OWSendCmd(ROM, OW_CONVERTT_CMD);
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
549
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
550 i = 0;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
551
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
552 /* Wait for the conversion */
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
553 while (OWReadBit() == 0)
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
554 i = 1;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
555
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
556 /* Check that we talked to a module and it did something */
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
557 if (i == 0) {
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
558 return OW_TEMP_NO_ROM;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
559 }
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
560
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
561 OWSendCmd(ROM, OW_RD_SCR_CMD);
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
562 crc = 0;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
563 for (i = 0; i < 8; i++) {
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
564 buf[i] = OWReadByte();
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
565 OWCRC(buf[i], &crc);
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
566 }
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
567 buf[i] = OWReadByte();
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
568 if (crc != buf[8])
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
569 return OW_TEMP_CRC_ERR;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
570 temp = buf[0];
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
571 if (buf[1] & 0x80)
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
572 temp -= 256;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
573
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
574 /* Chop off 0.5 degree bit */
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
575 temp >>= 1;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
576
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
577 /* Calulate the fractional remainder */
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
578 tfrac = buf[7] - buf[6];
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
579
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
580 /* Work in 100'th of degreess to save on floats */
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
581 tfrac *= (int16_t)100;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
582
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
583 /* Divide by count */
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
584 tfrac /= buf[7];
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
585
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
586 /* Subtract 0.25 deg from temp */
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
587 tfrac += 75;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
588 if (tfrac < 100)
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
589 temp--;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
590 else
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
591 tfrac -= 100;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
592
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
593 i = temp;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
594 temp *= 100;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
595 temp += tfrac;
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
596
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
597 return(temp);
5898fba6593c Add temperature control.
darius@inchoate.localdomain
parents: 33
diff changeset
598 }