C++ library, driver software code for the low-power small WLP package MAX31875 temperature sensor. Code supports one-shot, shut-down/standby, hysteresis, alarm limits.
Dependents: MAX31875_Temperature_Sensor_Small_Package
max31875.h@2:048eff228fd8, 2019-02-04 (annotated)
- Committer:
- phonemacro
- Date:
- Mon Feb 04 05:32:58 2019 +0000
- Revision:
- 2:048eff228fd8
- Parent:
- 1:98499c3dace6
updated documentation
Who changed what in which revision?
User | Revision | Line number | New contents of line |
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phonemacro | 0:f51465145906 | 1 | /******************************************************************************* |
phonemacro | 0:f51465145906 | 2 | * Copyright (C) 2019 Maxim Integrated Products, Inc., All Rights Reserved. |
phonemacro | 0:f51465145906 | 3 | * |
phonemacro | 0:f51465145906 | 4 | * Permission is hereby granted, free of charge, to any person obtaining a |
phonemacro | 0:f51465145906 | 5 | * copy of this software and associated documentation files (the "Software"), |
phonemacro | 0:f51465145906 | 6 | * to deal in the Software without restriction, including without limitation |
phonemacro | 0:f51465145906 | 7 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
phonemacro | 0:f51465145906 | 8 | * and/or sell copies of the Software, and to permit persons to whom the |
phonemacro | 0:f51465145906 | 9 | * Software is furnished to do so, subject to the following conditions: |
phonemacro | 0:f51465145906 | 10 | * |
phonemacro | 0:f51465145906 | 11 | * The above copyright notice and this permission notice shall be included |
phonemacro | 0:f51465145906 | 12 | * in all copies or substantial portions of the Software. |
phonemacro | 0:f51465145906 | 13 | * |
phonemacro | 0:f51465145906 | 14 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS |
phonemacro | 0:f51465145906 | 15 | * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
phonemacro | 0:f51465145906 | 16 | * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. |
phonemacro | 0:f51465145906 | 17 | * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES |
phonemacro | 0:f51465145906 | 18 | * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, |
phonemacro | 0:f51465145906 | 19 | * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR |
phonemacro | 0:f51465145906 | 20 | * OTHER DEALINGS IN THE SOFTWARE. |
phonemacro | 0:f51465145906 | 21 | * |
phonemacro | 0:f51465145906 | 22 | * Except as contained in this notice, the name of Maxim Integrated |
phonemacro | 0:f51465145906 | 23 | * Products, Inc. shall not be used except as stated in the Maxim Integrated |
phonemacro | 0:f51465145906 | 24 | * Products, Inc. Branding Policy. |
phonemacro | 0:f51465145906 | 25 | * |
phonemacro | 0:f51465145906 | 26 | * The mere transfer of this software does not imply any licenses |
phonemacro | 0:f51465145906 | 27 | * of trade secrets, proprietary technology, copyrights, patents, |
phonemacro | 0:f51465145906 | 28 | * trademarks, maskwork rights, or any other form of intellectual |
phonemacro | 0:f51465145906 | 29 | * property whatsoever. Maxim Integrated Products, Inc. retains all |
phonemacro | 0:f51465145906 | 30 | * ownership rights. |
phonemacro | 0:f51465145906 | 31 | ******************************************************************************* |
phonemacro | 0:f51465145906 | 32 | * @file MAX31875.h |
phonemacro | 0:f51465145906 | 33 | ******************************************************************************* |
phonemacro | 0:f51465145906 | 34 | */ |
phonemacro | 0:f51465145906 | 35 | #ifndef MAX31875_H |
phonemacro | 0:f51465145906 | 36 | #define MAX31875_H |
phonemacro | 0:f51465145906 | 37 | #include "mbed.h" |
phonemacro | 0:f51465145906 | 38 | |
phonemacro | 0:f51465145906 | 39 | #define MAX31875_NO_ERROR 0 |
phonemacro | 0:f51465145906 | 40 | #define MAX31875_ERROR -1 |
phonemacro | 0:f51465145906 | 41 | |
phonemacro | 0:f51465145906 | 42 | #define MAX31875_REG_TEMPERATURE 0X00 |
phonemacro | 0:f51465145906 | 43 | #define MAX31875_REG_CONFIGURATION 0X01 |
phonemacro | 0:f51465145906 | 44 | #define MAX31875_REG_THYST 0X02 |
phonemacro | 0:f51465145906 | 45 | #define MAX31875_REG_TOS 0X03 |
phonemacro | 0:f51465145906 | 46 | #define MAX31875_REG_MAX 0X03 |
phonemacro | 0:f51465145906 | 47 | |
phonemacro | 0:f51465145906 | 48 | #define MAX31875_CFG_ONE_SHOT_START (1) /* Start one-shot measurement */ |
phonemacro | 0:f51465145906 | 49 | |
phonemacro | 0:f51465145906 | 50 | #define MAX31875_CFG_CONV_RATE_0_25 (0x00 << 1) /* 0.25 conversions/sec */ |
phonemacro | 0:f51465145906 | 51 | #define MAX31875_CFG_CONV_RATE_1 (0x01 << 1) /* 1.0 conversions/sec */ |
phonemacro | 0:f51465145906 | 52 | #define MAX31875_CFG_CONV_RATE_4 (0x02 << 1) /* 4.0 conversions/sec */ |
phonemacro | 0:f51465145906 | 53 | #define MAX31875_CFG_CONV_RATE_8 (0x03 << 1) /* 8.0 conversions/sec */ |
phonemacro | 0:f51465145906 | 54 | #define MAX31875_WAIT_CONV_RATE_0_25 (4.0) |
phonemacro | 0:f51465145906 | 55 | #define MAX31875_WAIT_CONV_RATE_1 (1.0) |
phonemacro | 0:f51465145906 | 56 | #define MAX31875_WAIT_CONV_RATE_4 (0.25) |
phonemacro | 0:f51465145906 | 57 | #define MAX31875_WAIT_CONV_RATE_8 (0.125) |
phonemacro | 0:f51465145906 | 58 | |
phonemacro | 0:f51465145906 | 59 | #define MAX31875_CFG_RESOLUTION_9BIT (0x00 << 5) |
phonemacro | 0:f51465145906 | 60 | #define MAX31875_CFG_RESOLUTION_10BIT (0x01 << 5) |
phonemacro | 0:f51465145906 | 61 | #define MAX31875_CFG_RESOLUTION_11BIT (0x02 << 5) |
phonemacro | 0:f51465145906 | 62 | #define MAX31875_CFG_RESOLUTION_12BIT (0x03 << 5) |
phonemacro | 0:f51465145906 | 63 | |
phonemacro | 0:f51465145906 | 64 | #define MAX31875_CFG_NORMAL_FORMAT (0X00 << 7) |
phonemacro | 0:f51465145906 | 65 | #define MAX31875_CFG_EXTENDED_FORMAT (0X01 << 7) |
phonemacro | 0:f51465145906 | 66 | |
phonemacro | 0:f51465145906 | 67 | #define MAX31875_CFG_CONTINUOUS (0X00 << 8) |
phonemacro | 0:f51465145906 | 68 | #define MAX31875_CFG_SHUTDOWN (0X01 << 8) |
phonemacro | 0:f51465145906 | 69 | |
phonemacro | 0:f51465145906 | 70 | #define MAX31875_CFG_COMPARATOR_MODE (0X00 << 9) |
phonemacro | 0:f51465145906 | 71 | #define MAX31875_CFG_INTERRUPT_MODE (0X01 << 9) |
phonemacro | 0:f51465145906 | 72 | |
phonemacro | 0:f51465145906 | 73 | |
phonemacro | 0:f51465145906 | 74 | #define MAX31875_CFG_FAULT_FILTER_1 (0x00 << 11) |
phonemacro | 0:f51465145906 | 75 | #define MAX31875_CFG_FAULT_FILTER_2 (0x01 << 11) |
phonemacro | 0:f51465145906 | 76 | #define MAX31875_CFG_FAULT_FILTER_4 (0x02 << 11) |
phonemacro | 0:f51465145906 | 77 | #define MAX31875_CFG_FAULT_FILTER_6 (0x03 << 11) |
phonemacro | 0:f51465145906 | 78 | |
phonemacro | 0:f51465145906 | 79 | #define MAX31875_CFG_OVER_TEMP_MASK (0x80) |
phonemacro | 0:f51465145906 | 80 | |
phonemacro | 0:f51465145906 | 81 | |
phonemacro | 0:f51465145906 | 82 | #define MAX31875_I2C_SLAVE_ADR_R0 (0x90 >> 1) // code uses the 7 bit address |
phonemacro | 0:f51465145906 | 83 | #define MAX31875_I2C_SLAVE_ADR_R1 (0x92 >> 1) |
phonemacro | 0:f51465145906 | 84 | #define MAX31875_I2C_SLAVE_ADR_R2 (0x94 >> 1) |
phonemacro | 0:f51465145906 | 85 | #define MAX31875_I2C_SLAVE_ADR_R3 (0x96 >> 1) |
phonemacro | 0:f51465145906 | 86 | #define MAX31875_I2C_SLAVE_ADR_R4 (0x98 >> 1) |
phonemacro | 0:f51465145906 | 87 | #define MAX31875_I2C_SLAVE_ADR_R5 (0x9A >> 1) |
phonemacro | 0:f51465145906 | 88 | #define MAX31875_I2C_SLAVE_ADR_R6 (0x9C >> 1) |
phonemacro | 0:f51465145906 | 89 | #define MAX31875_I2C_SLAVE_ADR_R7 (0x9E >> 1) |
phonemacro | 0:f51465145906 | 90 | |
phonemacro | 0:f51465145906 | 91 | #define MAX31875_CF_NORMAL_FORMAT (0.00390625F) |
phonemacro | 0:f51465145906 | 92 | #define MAX31875_CF_EXTENDED_FORMAT (0.0078125F) |
phonemacro | 0:f51465145906 | 93 | |
phonemacro | 0:f51465145906 | 94 | /** |
phonemacro | 0:f51465145906 | 95 | * @brief Extremely small low-power temperature sensor. |
phonemacro | 0:f51465145906 | 96 | * @version 1.0000.0000 |
phonemacro | 0:f51465145906 | 97 | * |
phonemacro | 0:f51465145906 | 98 | * @details The MAX31875 is a small WLP package temperature sensor. |
phonemacro | 0:f51465145906 | 99 | * It supports high, low triggers stored in EEPROM for hystersis |
phonemacro | 0:f51465145906 | 100 | * or limit alarms using comparator or interrupt mode. |
phonemacro | 0:f51465145906 | 101 | * The MAX31875 can operate in shutdown and one-shot mode for |
phonemacro | 0:f51465145906 | 102 | * extremely low power applications. |
phonemacro | 0:f51465145906 | 103 | * Tiny size of 0.84 x 0.84 x 0.35 mm. |
phonemacro | 0:f51465145906 | 104 | * Accuracy is +-1.5°C from +10°C to +45°C (±0.5°C Typical), |
phonemacro | 0:f51465145906 | 105 | * +-2.0°C from -10°C to +100°C (±0.6°C Typical), |
phonemacro | 0:f51465145906 | 106 | * +-3.0°C from -20°C to +125°C (±1.0°C Typical), |
phonemacro | 0:f51465145906 | 107 | * I2C data rate of up to 1 MHz. |
phonemacro | 0:f51465145906 | 108 | * |
phonemacro | 0:f51465145906 | 109 | * @code |
phonemacro | 0:f51465145906 | 110 | * #include "mbed.h" |
phonemacro | 0:f51465145906 | 111 | * #include "max32630fthr.h" |
phonemacro | 0:f51465145906 | 112 | * #include "max31875.h" |
phonemacro | 0:f51465145906 | 113 | * #include "USBSerial.h" |
phonemacro | 0:f51465145906 | 114 | * MAX32630FTHR pegasus(MAX32630FTHR::VIO_1V8); |
phonemacro | 0:f51465145906 | 115 | * I2C i2cBus(P3_4, P3_5); |
phonemacro | 0:f51465145906 | 116 | * int main() |
phonemacro | 0:f51465145906 | 117 | * { |
phonemacro | 0:f51465145906 | 118 | * uint16_t raw; |
phonemacro | 0:f51465145906 | 119 | * float temperature; |
phonemacro | 0:f51465145906 | 120 | * DigitalOut rLED(LED1, LED_OFF); |
phonemacro | 0:f51465145906 | 121 | * DigitalOut gLED(LED2, LED_OFF); |
phonemacro | 0:f51465145906 | 122 | * DigitalOut bLED(LED3, LED_OFF); |
phonemacro | 0:f51465145906 | 123 | * gLED = LED_ON; |
phonemacro | 0:f51465145906 | 124 | * MAX31875 temp_sensor(i2cBus, MAX31875_I2C_SLAVE_ADR_R0); |
phonemacro | 0:f51465145906 | 125 | * i2cBus.frequency(1000000); |
phonemacro | 0:f51465145906 | 126 | * temp_sensor.write_reg(uint16_t(MAX31875_CFG_CONV_RATE_8 | |
phonemacro | 0:f51465145906 | 127 | * MAX31875_CFG_RESOLUTION_12BIT), MAX31875_REG_CONFIGURATION); |
phonemacro | 0:f51465145906 | 128 | * wait(MAX31875_WAIT_CONV_RATE_8); |
phonemacro | 0:f51465145906 | 129 | * temperature = temp_sensor.read_reg_as_temperature(MAX31875_REG_TEMPERATURE); |
phonemacro | 0:f51465145906 | 130 | * printf("Temperature = %3.4f Celsius, %3.4f Fahrenheit\r\n", |
phonemacro | 0:f51465145906 | 131 | * temperature, temp_sensor.celsius_to_fahrenheit(temperature)); |
phonemacro | 0:f51465145906 | 132 | * } |
phonemacro | 0:f51465145906 | 133 | * @endcode |
phonemacro | 0:f51465145906 | 134 | */ |
phonemacro | 0:f51465145906 | 135 | |
phonemacro | 0:f51465145906 | 136 | class MAX31875 |
phonemacro | 0:f51465145906 | 137 | { |
phonemacro | 0:f51465145906 | 138 | public: |
phonemacro | 0:f51465145906 | 139 | |
phonemacro | 0:f51465145906 | 140 | /**********************************************************//** |
phonemacro | 0:f51465145906 | 141 | * @brief Constructor for MAX31875 Class. |
phonemacro | 0:f51465145906 | 142 | * |
phonemacro | 0:f51465145906 | 143 | * @details Allows user to use existing I2C object |
phonemacro | 0:f51465145906 | 144 | * |
phonemacro | 0:f51465145906 | 145 | * On Entry: |
phonemacro | 0:f51465145906 | 146 | * @param[in] i2c_bus - pointer to existing I2C object |
phonemacro | 0:f51465145906 | 147 | * @param[in] i2c_adrs - 7-bit slave address of MAX31875 |
phonemacro | 0:f51465145906 | 148 | * |
phonemacro | 0:f51465145906 | 149 | * On Exit: |
phonemacro | 0:f51465145906 | 150 | * |
phonemacro | 0:f51465145906 | 151 | * @return None |
phonemacro | 0:f51465145906 | 152 | **************************************************************/ |
phonemacro | 0:f51465145906 | 153 | MAX31875(I2C &i2c_bus, uint8_t slaveAddress); |
phonemacro | 0:f51465145906 | 154 | |
phonemacro | 0:f51465145906 | 155 | /**********************************************************//** |
phonemacro | 0:f51465145906 | 156 | * @brief Default destructor for MAX31875 Class. |
phonemacro | 0:f51465145906 | 157 | * |
phonemacro | 0:f51465145906 | 158 | * @details Destroys I2C object if owner |
phonemacro | 0:f51465145906 | 159 | * |
phonemacro | 0:f51465145906 | 160 | * On Entry: |
phonemacro | 0:f51465145906 | 161 | * |
phonemacro | 0:f51465145906 | 162 | * On Exit: |
phonemacro | 0:f51465145906 | 163 | * |
phonemacro | 0:f51465145906 | 164 | * @return None |
phonemacro | 0:f51465145906 | 165 | **************************************************************/ |
phonemacro | 0:f51465145906 | 166 | ~MAX31875(); |
phonemacro | 0:f51465145906 | 167 | |
phonemacro | 0:f51465145906 | 168 | /** |
phonemacro | 0:f51465145906 | 169 | * @brief Read register of device at slave address |
phonemacro | 0:f51465145906 | 170 | * @param[out] value - Read data on success |
phonemacro | 0:f51465145906 | 171 | * @param reg - Register address |
phonemacro | 0:f51465145906 | 172 | * @return 0 on success, negative number on failure |
phonemacro | 0:f51465145906 | 173 | */ |
phonemacro | 0:f51465145906 | 174 | int read_reg(uint16_t *value, char reg); |
phonemacro | 0:f51465145906 | 175 | |
phonemacro | 0:f51465145906 | 176 | /** |
phonemacro | 0:f51465145906 | 177 | * @brief Reads the temperature registers |
phonemacro | 0:f51465145906 | 178 | * @param reg - the address of the temperature register |
phonemacro | 0:f51465145906 | 179 | * @return temprature in degrees Celsius |
phonemacro | 0:f51465145906 | 180 | */ |
phonemacro | 0:f51465145906 | 181 | float read_reg_as_temperature(uint8_t reg); |
phonemacro | 0:f51465145906 | 182 | |
phonemacro | 0:f51465145906 | 183 | /** |
phonemacro | 1:98499c3dace6 | 184 | * @brief Writes to the configuration register |
phonemacro | 1:98499c3dace6 | 185 | * @param cfg - configurate word |
phonemacro | 0:f51465145906 | 186 | * @return 0 on success, negative number on failure |
phonemacro | 0:f51465145906 | 187 | */ |
phonemacro | 0:f51465145906 | 188 | int write_cfg(uint16_t cfg); |
phonemacro | 0:f51465145906 | 189 | |
phonemacro | 0:f51465145906 | 190 | /** |
phonemacro | 1:98499c3dace6 | 191 | * @brief Writes to the THYST register |
phonemacro | 1:98499c3dace6 | 192 | * @param temperature - the temperature in Celsius degrees |
phonemacro | 0:f51465145906 | 193 | * @return 0 on success, negative number on failure |
phonemacro | 0:f51465145906 | 194 | */ |
phonemacro | 0:f51465145906 | 195 | int write_trip_low(float temperature); |
phonemacro | 0:f51465145906 | 196 | |
phonemacro | 0:f51465145906 | 197 | /** |
phonemacro | 1:98499c3dace6 | 198 | * @brief Writes to the TOS register |
phonemacro | 1:98499c3dace6 | 199 | * @param temperature - the temperature in Celsius degrees |
phonemacro | 0:f51465145906 | 200 | * @return 0 on success, negative number on failure |
phonemacro | 0:f51465145906 | 201 | */ |
phonemacro | 0:f51465145906 | 202 | int write_trip_high(float temperature); |
phonemacro | 0:f51465145906 | 203 | |
phonemacro | 0:f51465145906 | 204 | /** |
phonemacro | 1:98499c3dace6 | 205 | * @brief Converts Celsius degrees to Fahrenheit |
phonemacro | 0:f51465145906 | 206 | * @param temp_c - the temperature in Celsius degrees |
phonemacro | 1:98499c3dace6 | 207 | * @return temperature in Celsius degrees |
phonemacro | 0:f51465145906 | 208 | */ |
phonemacro | 0:f51465145906 | 209 | float celsius_to_fahrenheit(float temp_c); |
phonemacro | 0:f51465145906 | 210 | |
phonemacro | 0:f51465145906 | 211 | protected: |
phonemacro | 2:048eff228fd8 | 212 | /** @union max31875_raw_data |
phonemacro | 2:048eff228fd8 | 213 | * @brief union data structure for byte word manipulations |
phonemacro | 2:048eff228fd8 | 214 | */ |
phonemacro | 0:f51465145906 | 215 | union max31875_raw_data { |
phonemacro | 0:f51465145906 | 216 | struct { |
phonemacro | 0:f51465145906 | 217 | uint8_t lsb; |
phonemacro | 0:f51465145906 | 218 | uint8_t msb; |
phonemacro | 0:f51465145906 | 219 | }; |
phonemacro | 0:f51465145906 | 220 | uint16_t uwrd; |
phonemacro | 0:f51465145906 | 221 | int16_t swrd; |
phonemacro | 0:f51465145906 | 222 | }; |
phonemacro | 0:f51465145906 | 223 | |
phonemacro | 0:f51465145906 | 224 | /** |
phonemacro | 0:f51465145906 | 225 | * @brief Write a value to a register |
phonemacro | 0:f51465145906 | 226 | * @param value - value to write to the register |
phonemacro | 0:f51465145906 | 227 | * @param reg - register address |
phonemacro | 0:f51465145906 | 228 | * @return 0 on success, negative number on failure |
phonemacro | 0:f51465145906 | 229 | */ |
phonemacro | 0:f51465145906 | 230 | int write_reg(uint16_t value, char reg); |
phonemacro | 0:f51465145906 | 231 | |
phonemacro | 0:f51465145906 | 232 | private: |
phonemacro | 2:048eff228fd8 | 233 | /** @var m_i2c |
phonemacro | 2:048eff228fd8 | 234 | * @brief I2C object |
phonemacro | 2:048eff228fd8 | 235 | */ |
phonemacro | 0:f51465145906 | 236 | I2C &m_i2c; |
phonemacro | 2:048eff228fd8 | 237 | /** @var m_writeAddress, m_readAddress |
phonemacro | 2:048eff228fd8 | 238 | * @brief I2C address |
phonemacro | 2:048eff228fd8 | 239 | */ |
phonemacro | 0:f51465145906 | 240 | uint8_t m_writeAddress, m_readAddress; |
phonemacro | 2:048eff228fd8 | 241 | /** @var m_writeAddress, m_readAddress |
phonemacro | 2:048eff228fd8 | 242 | * @brief m_extended_format |
phonemacro | 2:048eff228fd8 | 243 | */ |
phonemacro | 0:f51465145906 | 244 | uint32_t m_extended_format; |
phonemacro | 0:f51465145906 | 245 | }; |
phonemacro | 0:f51465145906 | 246 | |
phonemacro | 0:f51465145906 | 247 | #endif/* MAX31875_H */ |