1 /* 2 * Author: William Penner <william.penner@intel.com> 3 * Copyright (c) 2014 Intel Corporation. 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining a copy 6 * of this software and associated documentation files (the "Software"), to deal 7 * in the Software without restriction, including without limitation the rights 8 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 9 * copies of the Software, and to permit persons to whom the Software is 10 * furnished to do so, subject to the following conditions: 11 * 12 * The above copyright notice and this permission notice shall be included in 13 * all copies or substantial portions of the Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 18 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 21 * THE SOFTWARE. 22 */ 23 24 #pragma once 25 26 #include <string> 27 #include <mraa/i2c.h> 28 #include <math.h> 29 30 #define AM2315_NAME "am2315" 31 #define AM2315_I2C_ADDRESS 0x5c 32 33 #define AM2315_READ 0x03 34 #define AM2315_WRITE 0x10 35 36 /* AM2315 Commands */ 37 #define AM2315_HUMIDITY 0x00 38 #define AM2315_TEMP 0x02 39 #define AM2315_MODEL 0x08 40 #define AM2315_VERSION 0x0A 41 #define AM2315_ID 0x0B 42 #define AM2315_STATUS 0x0F 43 #define AM2315_USER_A 0x10 44 #define AM2315_USER_B 0x12 45 46 #define AM2315_SAMPLE 2 47 48 #define HIGH_PRIORITY 99 49 50 namespace upm { 51 52 /** 53 * @brief AM2315 Temperature & Humidity Sensor library 54 * @defgroup am2315 libupm-am2315 55 * @ingroup adafruit i2c temp 56 */ 57 58 /** 59 * @library am2315 60 * @sensor am2315 61 * @comname AM2315 Temperature & Humidity Sensor 62 * @type temp 63 * @man adafruit 64 * @web http://www.adafruit.com/products/1293 65 * @con i2c 66 * 67 * @brief API for the AM2315 Temperature & Humidity Sensor 68 * 69 * AM2315 by Measurement Specialties 70 * (http://www.aosong.com/asp_bin/Products/en/AM2315.pdf) 71 * is a digital humidity sensor with temperature output. 72 * RH reports between 0 and 100%, and the temperature range is 73 * -40 to +125 degC. 74 * The sampling period of this sensor is 2 seconds. Reads occurring 75 * more often than that return cached data. 76 * 77 * @image html am2315.jpeg 78 * @snippet am2315.cxx Interesting 79 */ 80 class AM2315 { 81 public: 82 /** 83 * Instantiates an AM2315 object 84 * 85 * @param bus Number of the used bus 86 * @param devAddr Address of the used I2C device 87 * @param mode AM2315 oversampling 88 */ 89 AM2315 (int bus, int devAddr=AM2315_I2C_ADDRESS); 90 91 /** 92 * AM2315 object destructor; basically, it closes the I2C connection. 93 */ 94 ~AM2315 (); 95 96 /** 97 * Gets the current measured humidity [RH] 98 * 99 * Data is updated every 2 seconds - accesses occurring more often than 100 * that return cached data 101 */ 102 float getHumidity(void); 103 104 /** 105 * Gets the humidity cell temperature [degC] 106 * 107 * Data is updated every 2 seconds - accesses occurring more often than 108 * that return cached data 109 */ 110 float getTemperature(void); 111 112 /** 113 * Gets the humidity cell temperature [degF] 114 * 115 * Data is updated every 2 seconds - accesses occurring more often than 116 * that return cached data 117 */ 118 float getTemperatureF(void); 119 120 /** 121 * Function intended to test the device and verify it 122 * is operating correctly. 123 * 124 */ 125 int testSensor(void); 126 127 /** 128 * Writes a four-byte (32b) register 129 * 130 * Note: these access routines are not the normal accesses to an I2C 131 * device. AM2315 contains a microcontroller that manages the 132 * actual readings. These handlers then make requests over I2C using 133 * a protocol defined by AM2315. 134 * 135 * @param reg Address of the register 136 * @param ival 32b value 137 */ 138 int i2cWriteReg_32(int reg, uint32_t ival); 139 140 /** 141 * Writes a two-byte (16b) register 142 * 143 * @param reg Address of the register 144 * @param ival 16b value 145 */ 146 int i2cWriteReg_16(int reg, uint16_t ival); 147 148 /** 149 * Writes a one-byte (8b) register 150 * 151 * @param reg Address of the register 152 * @param ival 8b value 153 */ 154 int i2cWriteReg_8(int reg, uint8_t ival); 155 156 /** 157 * Reads a four-byte register 158 * 159 * @param reg Address of the register 160 */ 161 uint32_t i2cReadReg_32 (int reg); 162 163 /** 164 * Reads a two-byte register 165 * 166 * @param reg Address of the register 167 */ 168 uint16_t i2cReadReg_16 (int reg); 169 170 /** 171 * Reads a one-byte register 172 * 173 * @param reg Address of the register 174 */ 175 uint8_t i2cReadReg_8 (int reg); 176 177 private: 178 179 char* m_name; 180 181 int m_controlAddr; 182 int m_bus; 183 mraa_i2c_context m_i2ControlCtx; 184 185 void update_values(void); 186 uint8_t i2cReadReg(int reg, uint8_t* data, int ilen); 187 int i2cWriteReg(uint8_t reg, uint8_t* data, uint8_t ilen); 188 uint16_t crc16(uint8_t* ptr, uint8_t len); 189 190 int32_t m_temperature; 191 int32_t m_humidity; 192 193 uint16_t m_model; 194 uint16_t m_version; 195 uint32_t m_id; 196 197 time_t m_last_time; 198 199 int m_base_priority; 200 pthread_t this_thread; 201 }; 202 203 } 204