BULME_BHEL18 / LM75B

A feature complete driver for the LM75B temperature sensor from NXP.

Fork of LM75B by Neil Thiessen

LM75B.h@9:74b44a27fa40, 2013-08-28 (annotated)

Committer:
neilt6
Date:
Wed Aug 28 17:17:24 2013 +0000
Revision:
9:74b44a27fa40
Parent:
8:2b797c309258
Child:
10:51d149fa47bd
Added open() method to probe for and reset devices

Who changed what in which revision?

UserRevisionLine numberNew contents of line
neilt6 2:9ecc39b2ca70 1 /* LM75B Driver Library
neilt6 4:06676376766a 2 * Copyright (c) 2013 Neil Thiessen
neilt6 0:557a92280097 3 *
neilt6 3:9d68eed28bfb 4 * Licensed under the Apache License, Version 2.0 (the "License");
neilt6 3:9d68eed28bfb 5 * you may not use this file except in compliance with the License.
neilt6 3:9d68eed28bfb 6 * You may obtain a copy of the License at
neilt6 4:06676376766a 7 *
neilt6 4:06676376766a 8 * http://www.apache.org/licenses/LICENSE-2.0
neilt6 0:557a92280097 9 *
neilt6 3:9d68eed28bfb 10 * Unless required by applicable law or agreed to in writing, software
neilt6 3:9d68eed28bfb 11 * distributed under the License is distributed on an "AS IS" BASIS,
neilt6 3:9d68eed28bfb 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
neilt6 3:9d68eed28bfb 13 * See the License for the specific language governing permissions and
neilt6 3:9d68eed28bfb 14 * limitations under the License.
neilt6 0:557a92280097 15 */
neilt6 0:557a92280097 16
neilt6 0:557a92280097 17 #ifndef LM75B_H
neilt6 0:557a92280097 18 #define LM75B_H
neilt6 0:557a92280097 19
neilt6 0:557a92280097 20 #include "mbed.h"
neilt6 0:557a92280097 21
neilt6 0:557a92280097 22 /** LM75B class.
neilt6 0:557a92280097 23 * Used for controlling an LM75B temperature sensor connected via I2C.
neilt6 0:557a92280097 24 *
neilt6 0:557a92280097 25 * Example:
neilt6 0:557a92280097 26 * @code
neilt6 0:557a92280097 27 * #include "mbed.h"
neilt6 0:557a92280097 28 * #include "LM75B.h"
neilt6 0:557a92280097 29 *
neilt6 2:9ecc39b2ca70 30 * LM75B sensor(p28, p27, LM75B::ADDRESS_0);
neilt6 0:557a92280097 31 *
neilt6 9:74b44a27fa40 32 * int main()
neilt6 9:74b44a27fa40 33 * {
neilt6 9:74b44a27fa40 34 * //Try to open the LM75B
neilt6 9:74b44a27fa40 35 * if (sensor.open()) {
neilt6 9:74b44a27fa40 36 * printf("Device detected!\n");
neilt6 9:74b44a27fa40 37 *
neilt6 9:74b44a27fa40 38 * while (1) {
neilt6 9:74b44a27fa40 39 * //Read the temperature
neilt6 9:74b44a27fa40 40 * float temp = sensor.temp();
neilt6 0:557a92280097 41 *
neilt6 9:74b44a27fa40 42 * //Print the temperature
neilt6 9:74b44a27fa40 43 * printf("Temp = %.3f\n", temp);
neilt6 0:557a92280097 44 *
neilt6 9:74b44a27fa40 45 * //Sleep for 0.5 seconds
neilt6 9:74b44a27fa40 46 * wait(0.5);
neilt6 9:74b44a27fa40 47 * }
neilt6 9:74b44a27fa40 48 * } else {
neilt6 9:74b44a27fa40 49 * printf("Device not detected!\n");
neilt6 9:74b44a27fa40 50 * while (1);
neilt6 0:557a92280097 51 * }
neilt6 0:557a92280097 52 * }
neilt6 0:557a92280097 53 * @endcode
neilt6 0:557a92280097 54 */
neilt6 0:557a92280097 55 class LM75B
neilt6 0:557a92280097 56 {
neilt6 0:557a92280097 57 public:
neilt6 2:9ecc39b2ca70 58 /** Represents the different I2C address possibilities for the LM75B
neilt6 2:9ecc39b2ca70 59 */
neilt6 2:9ecc39b2ca70 60 enum Address {
neilt6 2:9ecc39b2ca70 61 ADDRESS_0 = (0x48 << 1), /**< A[2:0] pins = 000 */
neilt6 2:9ecc39b2ca70 62 ADDRESS_1 = (0x49 << 1), /**< A[2:0] pins = 001 */
neilt6 2:9ecc39b2ca70 63 ADDRESS_2 = (0x4A << 1), /**< A[2:0] pins = 010 */
neilt6 2:9ecc39b2ca70 64 ADDRESS_3 = (0x4B << 1), /**< A[2:0] pins = 011 */
neilt6 2:9ecc39b2ca70 65 ADDRESS_4 = (0x4C << 1), /**< A[2:0] pins = 100 */
neilt6 2:9ecc39b2ca70 66 ADDRESS_5 = (0x4D << 1), /**< A[2:0] pins = 101 */
neilt6 2:9ecc39b2ca70 67 ADDRESS_6 = (0x4E << 1), /**< A[2:0] pins = 110 */
neilt6 2:9ecc39b2ca70 68 ADDRESS_7 = (0x4F << 1) /**< A[2:0] pins = 111 */
neilt6 2:9ecc39b2ca70 69 };
neilt6 2:9ecc39b2ca70 70
neilt6 2:9ecc39b2ca70 71 /** Represents the power mode of the LM75B
neilt6 2:9ecc39b2ca70 72 */
neilt6 2:9ecc39b2ca70 73 enum PowerMode {
neilt6 2:9ecc39b2ca70 74 POWER_NORMAL, /**< Chip is enabled and samples every 100ms */
neilt6 2:9ecc39b2ca70 75 POWER_SHUTDOWN /**< Chip is in low-power shutdown mode */
neilt6 2:9ecc39b2ca70 76 };
neilt6 2:9ecc39b2ca70 77
neilt6 2:9ecc39b2ca70 78 /** Represents OS pin mode of the LM75B
neilt6 2:9ecc39b2ca70 79 */
neilt6 2:9ecc39b2ca70 80 enum OSMode {
neilt6 2:9ecc39b2ca70 81 OS_COMPARATOR, /**< OS is asserted when the temperature reaches the alert threshold, and de-asserted when the temperature drops below the alert hysteresis threshold */
neilt6 2:9ecc39b2ca70 82 OS_INTERRUPT /**< OS is asserted when the temperature reaches the alert threshold, or drops below the alert hysteresis threshold, and only de-asserted when a register has been read */
neilt6 2:9ecc39b2ca70 83 };
neilt6 2:9ecc39b2ca70 84
neilt6 2:9ecc39b2ca70 85 /** Represents OS pin polarity of the LM75B
neilt6 2:9ecc39b2ca70 86 */
neilt6 2:9ecc39b2ca70 87 enum OSPolarity {
neilt6 2:9ecc39b2ca70 88 OS_ACTIVE_LOW, /**< OS is a logic low when asserted, and a logic high when de-asserted */
neilt6 2:9ecc39b2ca70 89 OS_ACTIVE_HIGH /**< OS is a logic high when asserted, and a logic low when de-asserted */
neilt6 2:9ecc39b2ca70 90 };
neilt6 2:9ecc39b2ca70 91
neilt6 2:9ecc39b2ca70 92 /** Represents OS pin fault queue length of the LM75B
neilt6 2:9ecc39b2ca70 93 */
neilt6 2:9ecc39b2ca70 94 enum OSFaultQueue {
neilt6 2:9ecc39b2ca70 95 OS_FAULT_QUEUE_1, /**< OS is asserted after 1 fault */
neilt6 2:9ecc39b2ca70 96 OS_FAULT_QUEUE_2, /**< OS is asserted after 2 consecutive faults */
neilt6 2:9ecc39b2ca70 97 OS_FAULT_QUEUE_4, /**< OS is asserted after 4 consecutive faults */
neilt6 2:9ecc39b2ca70 98 OS_FAULT_QUEUE_6 /**< OS is asserted after 6 consecutive faults */
neilt6 2:9ecc39b2ca70 99 };
neilt6 2:9ecc39b2ca70 100
neilt6 0:557a92280097 101 /** Create an LM75B object connected to the specified I2C pins with the specified I2C slave address
neilt6 0:557a92280097 102 *
neilt6 7:bebde8098fca 103 * @param sda The I2C data pin.
neilt6 7:bebde8098fca 104 * @param scl The I2C clock pin.
neilt6 7:bebde8098fca 105 * @param addr The I2C slave address.
neilt6 0:557a92280097 106 */
neilt6 2:9ecc39b2ca70 107 LM75B(PinName sda, PinName scl, Address addr);
neilt6 2:9ecc39b2ca70 108
neilt6 9:74b44a27fa40 109 /** Probes for the LM75B and resets it to default configuration if present
neilt6 9:74b44a27fa40 110 *
neilt6 9:74b44a27fa40 111 * @returns
neilt6 9:74b44a27fa40 112 * 'true' if the device exists on the bus,
neilt6 9:74b44a27fa40 113 * 'false' if the device doesn't exist on the bus.
neilt6 9:74b44a27fa40 114 */
neilt6 9:74b44a27fa40 115 bool open(void);
neilt6 9:74b44a27fa40 116
neilt6 0:557a92280097 117 /** Get the current power mode of the LM75B
neilt6 0:557a92280097 118 *
neilt6 6:6b8a9d1ad49a 119 * @returns The current power mode as a PowerMode enum.
neilt6 0:557a92280097 120 */
neilt6 8:2b797c309258 121 LM75B::PowerMode powerMode(void);
neilt6 2:9ecc39b2ca70 122
neilt6 0:557a92280097 123 /** Set the power mode of the LM75B
neilt6 0:557a92280097 124 *
neilt6 6:6b8a9d1ad49a 125 * @param mode The new power mode as a PowerMode enum.
neilt6 0:557a92280097 126 */
neilt6 8:2b797c309258 127 void powerMode(PowerMode mode);
neilt6 2:9ecc39b2ca70 128
neilt6 0:557a92280097 129 /** Get the current OS pin mode of the LM75B
neilt6 0:557a92280097 130 *
neilt6 6:6b8a9d1ad49a 131 * @returns The current OS pin mode as an OSMode enum.
neilt6 0:557a92280097 132 */
neilt6 8:2b797c309258 133 LM75B::OSMode osMode(void);
neilt6 2:9ecc39b2ca70 134
neilt6 0:557a92280097 135 /** Set the OS pin mode of the LM75B
neilt6 0:557a92280097 136 *
neilt6 6:6b8a9d1ad49a 137 * @param mode The new OS pin mode as an OSMode enum.
neilt6 0:557a92280097 138 */
neilt6 8:2b797c309258 139 void osMode(OSMode mode);
neilt6 2:9ecc39b2ca70 140
neilt6 0:557a92280097 141 /** Get the current OS pin polarity of the LM75B
neilt6 0:557a92280097 142 *
neilt6 6:6b8a9d1ad49a 143 * @returns The current OS pin polarity as an OSPolarity enum.
neilt6 0:557a92280097 144 */
neilt6 8:2b797c309258 145 LM75B::OSPolarity osPolarity(void);
neilt6 2:9ecc39b2ca70 146
neilt6 0:557a92280097 147 /** Set the OS pin polarity of the LM75B
neilt6 0:557a92280097 148 *
neilt6 6:6b8a9d1ad49a 149 * @param polarity The new OS pin polarity as an OSPolarity enum.
neilt6 0:557a92280097 150 */
neilt6 8:2b797c309258 151 void osPolarity(OSPolarity polarity);
neilt6 2:9ecc39b2ca70 152
neilt6 0:557a92280097 153 /** Get the current OS pin fault queue length of the LM75B
neilt6 0:557a92280097 154 *
neilt6 6:6b8a9d1ad49a 155 * @returns The current OS pin fault queue length as an OSFaultQueue enum.
neilt6 0:557a92280097 156 */
neilt6 8:2b797c309258 157 LM75B::OSFaultQueue osFaultQueue(void);
neilt6 2:9ecc39b2ca70 158
neilt6 0:557a92280097 159 /** Set the OS pin fault queue length of the LM75B
neilt6 0:557a92280097 160 *
neilt6 6:6b8a9d1ad49a 161 * @param queue The new OS pin fault queue length as an OSFaultQueue enum.
neilt6 0:557a92280097 162 */
neilt6 8:2b797c309258 163 void osFaultQueue(OSFaultQueue queue);
neilt6 2:9ecc39b2ca70 164
neilt6 0:557a92280097 165 /** Get the current alert temperature threshold of the LM75B
neilt6 0:557a92280097 166 *
neilt6 6:6b8a9d1ad49a 167 * @returns The current alert temperature threshold in °C.
neilt6 0:557a92280097 168 */
neilt6 8:2b797c309258 169 float alertTemp(void);
neilt6 2:9ecc39b2ca70 170
neilt6 0:557a92280097 171 /** Set the alert temperature threshold of the LM75B
neilt6 0:557a92280097 172 *
neilt6 6:6b8a9d1ad49a 173 * @param temp The new alert temperature threshold in °C.
neilt6 0:557a92280097 174 */
neilt6 8:2b797c309258 175 void alertTemp(float temp);
neilt6 2:9ecc39b2ca70 176
neilt6 0:557a92280097 177 /** Get the current alert temperature hysteresis threshold of the LM75B
neilt6 0:557a92280097 178 *
neilt6 6:6b8a9d1ad49a 179 * @returns The current alert temperature hysteresis threshold in °C.
neilt6 0:557a92280097 180 */
neilt6 8:2b797c309258 181 float alertHyst(void);
neilt6 2:9ecc39b2ca70 182
neilt6 0:557a92280097 183 /** Set the alert temperature hysteresis threshold of the LM75B
neilt6 0:557a92280097 184 *
neilt6 6:6b8a9d1ad49a 185 * @param temp The new alert temperature hysteresis threshold in °C.
neilt6 0:557a92280097 186 */
neilt6 8:2b797c309258 187 void alertHyst(float temp);
neilt6 2:9ecc39b2ca70 188
neilt6 0:557a92280097 189 /** Get the current temperature measurement of the LM75B
neilt6 0:557a92280097 190 *
neilt6 6:6b8a9d1ad49a 191 * @returns The current temperature measurement in °C.
neilt6 0:557a92280097 192 */
neilt6 8:2b797c309258 193 float temp(void);
neilt6 0:557a92280097 194
neilt6 0:557a92280097 195 private:
neilt6 8:2b797c309258 196 //I2C register addresses
neilt6 8:2b797c309258 197 enum Register {
neilt6 8:2b797c309258 198 REG_TEMP = 0x00,
neilt6 8:2b797c309258 199 REG_CONF = 0x01,
neilt6 8:2b797c309258 200 REG_THYST = 0x02,
neilt6 8:2b797c309258 201 REG_TOS = 0x03
neilt6 8:2b797c309258 202 };
neilt6 8:2b797c309258 203
neilt6 8:2b797c309258 204 //Member variables
neilt6 8:2b797c309258 205 I2C m_I2C;
neilt6 8:2b797c309258 206 int m_Addr;
neilt6 8:2b797c309258 207
neilt6 8:2b797c309258 208 //Internal functions
neilt6 8:2b797c309258 209 char read8(char reg);
neilt6 8:2b797c309258 210 void write8(char reg, char data);
neilt6 8:2b797c309258 211 unsigned short read16(char reg);
neilt6 8:2b797c309258 212 void write16(char reg, unsigned short data);
neilt6 8:2b797c309258 213 float readAlertTempHelper(char reg);
neilt6 8:2b797c309258 214 void writeAlertTempHelper(char reg, float temp);
neilt6 0:557a92280097 215 };
neilt6 0:557a92280097 216
neilt6 5:f8b36d66b768 217 #endif