Takuo WATANABE / STTS751

A library for STMicroelectronics STTS751 I2C temperature sensor

Dependents:   STTS751_Demo

STTS751.h@3:f9d3008f7e8f, 2014-02-05 (annotated)

Committer:
takuo
Date:
Wed Feb 05 04:24:36 2014 +0000
Revision:
3:f9d3008f7e8f
Parent:
2:3116fe4a0079 
Standby mode is now supported.; Conversion rate can be changed.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
takuo 1:b0a3645a3dba 1 /* A library for STMicroelectronics STTS751 I2C temperature sensor
takuo 0:4211e78bfa5d 2 * Copyright 2014, Takuo WATANABE (wtakuo)
takuo 0:4211e78bfa5d 3 *
takuo 0:4211e78bfa5d 4 * Licensed under the Apache License, Version 2.0 (the "License");
takuo 0:4211e78bfa5d 5 * you may not use this file except in compliance with the License.
takuo 0:4211e78bfa5d 6 * You may obtain a copy of the License at
takuo 0:4211e78bfa5d 7 *
takuo 0:4211e78bfa5d 8 * http://www.apache.org/licenses/LICENSE-2.0
takuo 0:4211e78bfa5d 9 *
takuo 0:4211e78bfa5d 10 * Unless required by applicable law or agreed to in writing, software
takuo 0:4211e78bfa5d 11 * distributed under the License is distributed on an "AS IS" BASIS,
takuo 0:4211e78bfa5d 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
takuo 0:4211e78bfa5d 13 * See the License for the specific language governing permissions and
takuo 0:4211e78bfa5d 14 * limitations under the License.
takuo 0:4211e78bfa5d 15 */
takuo 0:4211e78bfa5d 16
takuo 0:4211e78bfa5d 17 #ifndef STTS751_H
takuo 0:4211e78bfa5d 18 #define STTS751_H
takuo 0:4211e78bfa5d 19
takuo 0:4211e78bfa5d 20 #include "mbed.h"
takuo 0:4211e78bfa5d 21
takuo 0:4211e78bfa5d 22 /** A library for STMicroelectronics STTS751 I2C temperature sensor
takuo 3:f9d3008f7e8f 23 *
takuo 0:4211e78bfa5d 24 * http://www.st.com/web/catalog/sense_power/FM89/SC294/PF220116
takuo 0:4211e78bfa5d 25 *
takuo 0:4211e78bfa5d 26 * Example:
takuo 0:4211e78bfa5d 27 * @code
takuo 0:4211e78bfa5d 28 * #include "mbed.h"
takuo 0:4211e78bfa5d 29 * #include "STTS751.h"
takuo 0:4211e78bfa5d 30 *
takuo 0:4211e78bfa5d 31 * // I2C pins: p9 = sda, p10 = scl
takuo 3:f9d3008f7e8f 32 * STTS751 sensor(p9, p10);
takuo 0:4211e78bfa5d 33 *
takuo 0:4211e78bfa5d 34 * // You can specify an I2C object instead.
takuo 0:4211e78bfa5d 35 * // I2C i2c(p2, p10);
takuo 3:f9d3008f7e8f 36 * // STTS751 sensor(i2c);
takuo 0:4211e78bfa5d 37 *
takuo 0:4211e78bfa5d 38 * int main() {
takuo 2:3116fe4a0079 39 * // set the temperature resolution to 12bits
takuo 3:f9d3008f7e8f 40 * sensor.setResolution(STTS751::RES_12);
takuo 0:4211e78bfa5d 41 * while (true) {
takuo 3:f9d3008f7e8f 42 * printf("tmp: %.4f\n", (float)sensor);
takuo 0:4211e78bfa5d 43 * wait(1);
takuo 0:4211e78bfa5d 44 * }
takuo 0:4211e78bfa5d 45 * }
takuo 0:4211e78bfa5d 46 * @endcode
takuo 0:4211e78bfa5d 47 */
takuo 3:f9d3008f7e8f 48 class STTS751 {
takuo 0:4211e78bfa5d 49 public:
takuo 0:4211e78bfa5d 50 /** Device models
takuo 0:4211e78bfa5d 51 */
takuo 0:4211e78bfa5d 52 enum Model {
takuo 3:f9d3008f7e8f 53 MODEL_0 = 0x00, /**< Model 0 (default) */
takuo 3:f9d3008f7e8f 54 MODEL_1 = 0x40 /**< Model 1 */
takuo 0:4211e78bfa5d 55 };
takuo 0:4211e78bfa5d 56
takuo 3:f9d3008f7e8f 57 /** I2C slave address selectors
takuo 3:f9d3008f7e8f 58 * The I2C slave address of the device is determined by the pull up register for Addr/~Therm pin.
takuo 3:f9d3008f7e8f 59 *
takuo 0:4211e78bfa5d 60 */
takuo 0:4211e78bfa5d 61 enum Address {
takuo 0:4211e78bfa5d 62 ADDRESS_0 = (0x48 << 1), /**< pull up resistor = 7.5K */
takuo 0:4211e78bfa5d 63 ADDRESS_1 = (0x49 << 1), /**< pull up resistor = 12K */
takuo 0:4211e78bfa5d 64 ADDRESS_2 = (0x38 << 1), /**< pull up resistor = 20K */
takuo 0:4211e78bfa5d 65 ADDRESS_3 = (0x39 << 1) /**< pull up resistor = 33K or GND (default) */
takuo 0:4211e78bfa5d 66 };
takuo 0:4211e78bfa5d 67
takuo 2:3116fe4a0079 68 /** Temperature resolutions
takuo 2:3116fe4a0079 69 */
takuo 2:3116fe4a0079 70 enum Resolution {
takuo 3:f9d3008f7e8f 71 RES_9 = 0x08, /**< 9 bits */
takuo 2:3116fe4a0079 72 RES_10 = 0x00, /**< 10 bits (default) */
takuo 2:3116fe4a0079 73 RES_11 = 0x04, /**< 11 bits */
takuo 3:f9d3008f7e8f 74 RES_12 = 0x0c /**< 12 bits */
takuo 2:3116fe4a0079 75 };
takuo 2:3116fe4a0079 76
takuo 0:4211e78bfa5d 77 /** Create an STTS751 object connected to the specified I2C pins.
takuo 0:4211e78bfa5d 78 *
takuo 3:f9d3008f7e8f 79 * @param sda I2C data pin
takuo 3:f9d3008f7e8f 80 * @param scl I2C clock pin
takuo 3:f9d3008f7e8f 81 * @param standby Standby mode (defaults to false)
takuo 3:f9d3008f7e8f 82 * @param addr I2C slave address (defaults to ADDRESS_3)
takuo 3:f9d3008f7e8f 83 * @param model Device model (defaults to MODEL_0)
takuo 0:4211e78bfa5d 84 */
takuo 3:f9d3008f7e8f 85 STTS751(PinName sda, PinName scl,
takuo 3:f9d3008f7e8f 86 bool standby = false, Address addr = ADDRESS_3, Model model = MODEL_0);
takuo 3:f9d3008f7e8f 87
takuo 0:4211e78bfa5d 88
takuo 0:4211e78bfa5d 89 /** Create an STTS751 object connected to the specified I2C port.
takuo 0:4211e78bfa5d 90 *
takuo 3:f9d3008f7e8f 91 * @param i2c I2C port
takuo 3:f9d3008f7e8f 92 * @param standby Standby mode (defaults to false)
takuo 3:f9d3008f7e8f 93 * @param addr I2C slave address (defaults to ADDRESS_3)
takuo 3:f9d3008f7e8f 94 * @param model Device model (defaults to MODEL_0)
takuo 0:4211e78bfa5d 95 */
takuo 3:f9d3008f7e8f 96 STTS751(I2C &_i2c,
takuo 3:f9d3008f7e8f 97 bool standby = false, Address addr = ADDRESS_3, Model model = MODEL_0);
takuo 0:4211e78bfa5d 98
takuo 2:3116fe4a0079 99 /** Initialize the device
takuo 2:3116fe4a0079 100 */
takuo 2:3116fe4a0079 101 void init();
takuo 2:3116fe4a0079 102
takuo 3:f9d3008f7e8f 103 /** The I2C slave address (8bit) of the device
takuo 3:f9d3008f7e8f 104 *
takuo 3:f9d3008f7e8f 105 * @returns The I2C slave address (8bit) of the device
takuo 2:3116fe4a0079 106 */
takuo 2:3116fe4a0079 107 int addr();
takuo 2:3116fe4a0079 108
takuo 2:3116fe4a0079 109 /** Get the current temperature resolution
takuo 2:3116fe4a0079 110 *
takuo 2:3116fe4a0079 111 * @returns The current temperature resolution
takuo 2:3116fe4a0079 112 */
takuo 2:3116fe4a0079 113 Resolution resolution();
takuo 2:3116fe4a0079 114
takuo 2:3116fe4a0079 115 /** Set the temperature resolution
takuo 2:3116fe4a0079 116 *
takuo 2:3116fe4a0079 117 * @param res Resolution (defaults to RES_10)
takuo 2:3116fe4a0079 118 */
takuo 2:3116fe4a0079 119 void setResolution(Resolution res = RES_10);
takuo 2:3116fe4a0079 120
takuo 3:f9d3008f7e8f 121 /** Get the current conversion rate
takuo 3:f9d3008f7e8f 122 *
takuo 3:f9d3008f7e8f 123 * @returns The current conversion rate
takuo 3:f9d3008f7e8f 124 */
takuo 3:f9d3008f7e8f 125 int conversionRate();
takuo 3:f9d3008f7e8f 126
takuo 3:f9d3008f7e8f 127 /** Set the conversion rate
takuo 3:f9d3008f7e8f 128 * Set the number of times the temperature value is updated each second.
takuo 3:f9d3008f7e8f 129 * The conversion rate (times/second) can be calculated by 2^(rate - 4).
takuo 3:f9d3008f7e8f 130 * Note that rate should be less than 8 if the temperature resolution is 12-bit and
takuo 3:f9d3008f7e8f 131 * should be less than 9 if the temperature resolution is greater than 10-bit
takuo 3:f9d3008f7e8f 132 *
takuo 3:f9d3008f7e8f 133 * @param rate Conversion rate (0 .. 9)
takuo 3:f9d3008f7e8f 134 */
takuo 3:f9d3008f7e8f 135 void setConversionRate(int rate);
takuo 3:f9d3008f7e8f 136
takuo 3:f9d3008f7e8f 137 /** Set the device mode
takuo 3:f9d3008f7e8f 138 *
takuo 3:f9d3008f7e8f 139 * @param standby true : standby mode, false : continuous conversion mode
takuo 3:f9d3008f7e8f 140 */
takuo 3:f9d3008f7e8f 141 void setStandbyMode(bool standby);
takuo 3:f9d3008f7e8f 142
takuo 3:f9d3008f7e8f 143 /** Start a temperature conversion (in standby mode)
takuo 3:f9d3008f7e8f 144 */
takuo 3:f9d3008f7e8f 145 void start();
takuo 3:f9d3008f7e8f 146
takuo 3:f9d3008f7e8f 147 /** Checks that a temperature conversion has finished and the temperature value is available
takuo 3:f9d3008f7e8f 148 *
takuo 3:f9d3008f7e8f 149 * @returns true if a temperature conversion has finished and the temperature value is available
takuo 3:f9d3008f7e8f 150 */
takuo 3:f9d3008f7e8f 151 bool ready();
takuo 3:f9d3008f7e8f 152
takuo 0:4211e78bfa5d 153 /** Obtain the current temperature measurement
takuo 0:4211e78bfa5d 154 *
takuo 3:f9d3008f7e8f 155 * @param nowait If true, read the temperature value without waiting for finishing a conversion (in standby mode)
takuo 3:f9d3008f7e8f 156 * @returns The current temperature measurement in Celsius.
takuo 0:4211e78bfa5d 157 */
takuo 3:f9d3008f7e8f 158 float temp(bool nowait = false);
takuo 3:f9d3008f7e8f 159
takuo 0:4211e78bfa5d 160 #ifdef MBED_OPERATORS
takuo 0:4211e78bfa5d 161 /** A shorthand for temp()
takuo 0:4211e78bfa5d 162 *
takuo 0:4211e78bfa5d 163 * @returns The current temperature measurement in Celsius.
takuo 0:4211e78bfa5d 164 */
takuo 0:4211e78bfa5d 165 operator float();
takuo 0:4211e78bfa5d 166 #endif
takuo 0:4211e78bfa5d 167
takuo 0:4211e78bfa5d 168 protected:
takuo 3:f9d3008f7e8f 169 /** I2C registers
takuo 3:f9d3008f7e8f 170 */
takuo 2:3116fe4a0079 171 enum {
takuo 0:4211e78bfa5d 172 REG_TEMPERATURE_H = 0x00,
takuo 0:4211e78bfa5d 173 REG_STATUS = 0x01,
takuo 0:4211e78bfa5d 174 REG_TEMPERATURE_L = 0x02,
takuo 0:4211e78bfa5d 175 REG_CONFIGURATION = 0x03,
takuo 0:4211e78bfa5d 176 REG_CONV_RATE = 0x04,
takuo 0:4211e78bfa5d 177 REG_HIGH_LIMIT_H = 0x05,
takuo 0:4211e78bfa5d 178 REG_HIGH_LIMIT_L = 0x06,
takuo 0:4211e78bfa5d 179 REG_LOW_LIMIT_H = 0x07,
takuo 0:4211e78bfa5d 180 REG_LOW_LIMIT_L = 0x08,
takuo 0:4211e78bfa5d 181 REG_ONESHOT = 0x0f,
takuo 0:4211e78bfa5d 182 REG_THERM = 0x20,
takuo 0:4211e78bfa5d 183 REG_THERM_HYSTERESIS = 0x21,
takuo 0:4211e78bfa5d 184 REG_SMBUS_TIMEOUT = 0x22,
takuo 0:4211e78bfa5d 185 REG_PRODUCT_ID = 0xfd,
takuo 0:4211e78bfa5d 186 REG_MFG_ID = 0xfe,
takuo 2:3116fe4a0079 187 REG_REVISION_ID = 0xff,
takuo 3:f9d3008f7e8f 188 };
takuo 3:f9d3008f7e8f 189
takuo 3:f9d3008f7e8f 190 /** Configuration register (default 0x00)
takuo 3:f9d3008f7e8f 191 * - b7 : MASK1
takuo 3:f9d3008f7e8f 192 * - b6 : ~RUN/STOP (0 : continuous conversion mode, 1 : standby mode)
takuo 3:f9d3008f7e8f 193 * - b5 : 0
takuo 3:f9d3008f7e8f 194 * - b4 : RFU
takuo 3:f9d3008f7e8f 195 * - b3 : Tres1
takuo 3:f9d3008f7e8f 196 * - b2 : Tres0
takuo 3:f9d3008f7e8f 197 * - b1-b0 : RFU
takuo 3:f9d3008f7e8f 198 */
takuo 3:f9d3008f7e8f 199 enum {
takuo 3:f9d3008f7e8f 200 CONF_MASK1 = 0x80,
takuo 3:f9d3008f7e8f 201 CONF_RUNSTOP = 0x40,
takuo 3:f9d3008f7e8f 202 CONF_RES_MASK = 0x0c,
takuo 3:f9d3008f7e8f 203 };
takuo 3:f9d3008f7e8f 204
takuo 3:f9d3008f7e8f 205 /** Status Register (default undefined)
takuo 3:f9d3008f7e8f 206 * - b7 : Busy
takuo 3:f9d3008f7e8f 207 * - b6 : T_HIGH
takuo 3:f9d3008f7e8f 208 * - b5 : T_LOW
takuo 3:f9d3008f7e8f 209 * - b4-b1 : RFU
takuo 3:f9d3008f7e8f 210 * - b0 : THRM
takuo 3:f9d3008f7e8f 211 */
takuo 3:f9d3008f7e8f 212 enum {
takuo 3:f9d3008f7e8f 213 STATUS_BUSY = 0x80,
takuo 3:f9d3008f7e8f 214 STATUS_THIGH = 0x40,
takuo 3:f9d3008f7e8f 215 STATUS_LOW = 0x20,
takuo 3:f9d3008f7e8f 216 STATUS_THURM = 0x01
takuo 3:f9d3008f7e8f 217 };
takuo 3:f9d3008f7e8f 218
takuo 3:f9d3008f7e8f 219 /** Conversion Rate Register (default 4)
takuo 3:f9d3008f7e8f 220 * - b7-b4: 0
takuo 3:f9d3008f7e8f 221 * - b3-b0: Conversion rate (0..9)
takuo 3:f9d3008f7e8f 222 */
takuo 3:f9d3008f7e8f 223 enum {
takuo 3:f9d3008f7e8f 224 CONV_RATE_MASK = 0x0f
takuo 0:4211e78bfa5d 225 };
takuo 0:4211e78bfa5d 226
takuo 0:4211e78bfa5d 227 I2C _i2c;
takuo 0:4211e78bfa5d 228 const int _addr;
takuo 3:f9d3008f7e8f 229 bool _standby;
takuo 0:4211e78bfa5d 230
takuo 0:4211e78bfa5d 231 char read8(char reg);
takuo 2:3116fe4a0079 232 void write8(char reg, char data);
takuo 0:4211e78bfa5d 233 };
takuo 0:4211e78bfa5d 234
takuo 2:3116fe4a0079 235 #endif