/* * Author: Marc Graham * Copyright (c) 2015 Intel Corporation. * * This program and the accompanying materials are made available under the * terms of the The MIT License which is available at * https://opensource.org/licenses/MIT. * * SPDX-License-Identifier: MIT */ #pragma once #include #include #include #define MCP9808_REG_CONFIG 0x01 #define MCP9808_REG_AMBIENT_TEMP 0x05 #define MCP9808_REG_MANUF_ID 0x06 #define MCP9808_REG_DEVICE_ID 0x07 #define MCP9808_REG_RESOLUTION 0x08 #define MCP9808_CONFIG_SHUTDOWN 0x0001 #define MCP9808_CONFIG_CRITLOCKED 0x8000 #define MCP9808_CONFIG_WINLOCKED 0x4000 #define MCP9808_CONFIG_INTCLR 0x2000 namespace mraa { class I2c;} namespace upm { /** * @brief MCP9808 Precision Temperature Sensor * @defgroup mcp9808 libupm-mcp9808 * @ingroup adafruit i2c temp */ /** * @library mcp9808 * @sensor MCP9808 * @comname High Accuracy I2C Temperature Sensor * @type temp * @man adafruit * @con i2c * @web https://learn.adafruit.com/adafruit-mcp9808-precision-i2c-temperature-sensor-guide/overview * @web http://ww1.microchip.com/downloads/en/DeviceDoc/25095A.pdf * * @brief API for MCP9808 precision temprature sensor * * The MCP9808 digital temperature sensor converts temperatures between -20 deg C and +100 deg C * to a digital word with +/- 0.5 deg C (max.) accuracy. The MCP9808 comes with user-programmable * registers that provide flexibility for temperature sensing applications. The registers * allow user-selectable settings such as Shutdown or low-power modes and the specification * of temperature Event and Critical output boundaries. When the temperature changes beyond * the specified boundary limits, the MCP9808 outputs an Event signal. The user has the * option of setting the event output signal polarity as an active-low or active-high * comparator output for thermostat operation, or as temperature event interrupt output * for microprocessor-based systems. The event output can also be configured as a Critical * temperature output. * * Tested with Adafriut MCP9808 board. * * @image html mcp9808.jpg * @snippet mcp9808.cxx Interesting */ class MCP9808 : virtual public iTemperature { public: /** * @enum MCP9808_REG * @brief uint8_t enum containing register addresses * used for setting temp thresholds for MCP9808 * * @var MCP9808_REG::UPPER_TEMP = 0x02 * @var MCP9808_REG::LOWER_TEMP = 0x03 * @var MCP9808_REG::CRIT_TEMP = 0x04 */ typedef enum { UPPER_TEMP = 0x02, LOWER_TEMP = 0x03, CRIT_TEMP = 0x04, } MCP9808_REG; /** * @enum MCP9808_RESOLUTION * @brief uint8_t enum containing the four possible * values for MCP9808 resolution register. * * @var MCP9808_RESOLUTION::RES_LOW = 0.5C * @var MCP9808_RESOLUTION::RES_MEDIUM = 0.25C * @var MCP9808_RESOLUTION::RES_HIGH = 0.125C * @var MCP9808_RESOLUTION::RES_PRECISION = (default) 0.0625C */ typedef enum { RES_LOW = 0x00, RES_MEDIUM = 0x01, RES_HIGH = 0x02, RES_PRECISION = 0x03 } MCP9808_RESOLUTION; /** * @enum MCP9808_CONFIG * @brief uint16_t enum containing alert and hysteresis options * for config register. * * @var MCP9808_CONFIG::ALERTSTAT - Alert Output Status bit * 0 = Alert output is not asserted by the device (power-up default) * 1 = Alert output is asserted as a comparator/Interrupt or critical * temperature output * @var MCP9808_CONFIG::ALERTCTRL - Alert Output Control bit * 0 = Disabled (power-up default) * 1 = Enabled * @var MCP9808_CONFIG::ALERTSEL - Alert Output Select bit * 0 = Alert output for TUPPER, TLOWER and TCRIT (power-up default) * 1 = TA > TCRIT only (TUPPER and TLOWER temperature boundaries are disabled) * @var MCP9808_CONFIG::ALERTPOL - Alert Output Polarity bit * 0 = Active-low (power-up default; pull-up resistor required) * 1 = Active-high * @var MCP9808_CONFIG::ALERTMODE - Alert Output Mode bit * 0 = Comparator output (power-up default) * 1 = Interrupt output * @var MCP9808_CONFIG::HYST_0 : 0 deg C * @var MCP9808_CONFIG::HYST_1_5 : +1.5 deg C * @var MCP9808_CONFIG::HYST_3_0 : +3.0 deg C * @var MCP9808_CONFIG::HYST_6_0 : +6.0 deg C */ typedef enum { ALERTSTAT = 0x1000, ALERTCTRL = 0x0800, ALERTSEL = 0x0400, ALERTPOL = 0x0200, ALERTMODE = 0x0100, HYST_0 = 0x0000, HYST_1_5 = 0x0002, HYST_3_0 = 0x0004, HYST_6_0 = 0x0006 } MCP9808_CONFIG; /** * MCP9808 constructor * * @param bus i2c bus the sensor is attached to. * @param address Device address. Default is 0x18. */ MCP9808 (int bus, uint8_t address = 0x18); /** * MCP9808 destructor */ ~MCP9808 (); /** * Returns the name of the sensor */ std::string name() { return m_name; } /** * Returns current temperature. */ float getTemp(void); /** * Returns the temperature in degrees Celsius * * @return The Temperature in degrees Celsius */ virtual float getTemperature(); /** * Will cause the devices to either sleep or wakeup. * * @param sleep Bool, default true to sleep. false to wake. */ void shutDown(bool sleep = true); /** * setMode - sets temperature reporting mode. * * @param celsius Default is true. If false all * temps will be reported in fahrenheit. */ void setMode(bool celsius = true) { m_celsius = celsius; } /** * Returns true if mode is celsius * False if fahrenheit. */ bool isCelsius(void) { return m_celsius; } /** * Returns true if TCrit threshold has been crossed * Reflects the state of the bit based on the most recent * readTemp() operation. */ bool isTcrit() { return m_tcrit; } /** * Returns true if TUpper threshold crossed * Reflects the state of the bit based on the most recent * readTemp() operation. */ bool isTupper() { return m_tupper; } /** * Returns true if TLower threshold crossed. * Reflects the state of the bit based on the most recent * readTemp() operation. */ bool isTlower() { return m_tlower; } /** * Sets the value of TCrit, TUpper,TLower registers. * * @praam reg - MCP9808_REG enum UPPER_TEMP, LOWER_TEMP * or CRIT_TEMP. * @param value - float value representing the set value */ void setMonitorReg(MCP9808_REG reg, float value); /** * Returns the current value of TCrit, TUpper, TLower * registers. * * @param reg - MCP9808_REG enum UPPER_TEMP, LOWER_TEMP * or CRIT_TEMP. */ float getMonitorReg(MCP9808_REG reg); /** * Clears the interrupt when ALERT_MODE is set to * interrupt output and temp threshold crossed. */ void clearInterrupt(void); /** * Sets alert mode. Can use values from MCP9808_CONFIG * enum. Values can be combined. * * @param command - a combination of options to set desired * alert mode. See spcec sheet. */ void setAlertMode(uint16_t command); /** * Clears Alert Mode -- sets all params to default. */ void clearAlertMode(void); /** * Sets hysteresis value. * * @param value MCP9808_CONFIG enum value HYST_0, HYST_1_5, * HYST_3_0 or HYST_6_0 */ void setHysteresis(MCP9808_CONFIG value); /** * Returns hysteresis setting as a float value. */ float getHysteresis(); /** * Sets resolution of temperature conversion. * * @param value - MCP9808_RESOLUTION enum value. * RES_LOW = +0.5 C * RES_MEDIUM = +0.25 C * RES_HIGH = +0.125 C * RES_PRECISION = +0.0625 C (default). */ void setResolution(MCP9808_RESOLUTION value); /** * Returns float value representing the current * resolution setting. */ float getResolution(); /** * Returns Manufacturer ID. Typically 0x0054; */ uint16_t getManufacturer(); /** * Returns device ID and revision. Typically 0x0400 * With ID in the High byte. */ uint16_t getDevicedId(); private: /* Disable implicit copy and assignment operators */ MCP9808(const MCP9808&) = delete; MCP9808 &operator=(const MCP9808&) = delete; std::string m_name; bool m_celsius; bool m_tcrit; bool m_tupper; bool m_tlower; mraa::I2c* i2c; float getTempValue(uint16_t value); void updateConfigRegister(uint16_t update, bool on = true); uint16_t swapWord(uint16_t value); }; }