new sensor SENSIRION SHT31 - incompatible with Mayfly1.x which has th…

…e SHT41, both use same I2C addr 0x44

src/sensors/SensirionSHT3x.cpp

@@ -0,0 +1,168 @@
+/**
+ * @file SensirionSHT3x.cpp
+ * @copyright 2023 Neil Hancock, modified from SensironSHT4x
+ * @copyright 2017-2022 Stroud Water Research Center
+ * Part of the EnviroDIY ModularSensors library for Arduino
+ * @author Sara Geleskie Damiano <[email protected]>
+ *
+ * @brief Implements the SensirionSHT3x class.
+ */
+
+#include "SensirionSHT3x.h"
+
+
+// The constructors
+SensirionSHT3x::SensirionSHT3x(TwoWire* theI2C, int8_t powerPin, bool useHeater,
+                               uint8_t measurementsToAverage)
+    : Sensor("SensirionSHT3x", SHT3X_NUM_VARIABLES, SHT3X_WARM_UP_TIME_MS,
+             SHT3X_STABILIZATION_TIME_MS, SHT3X_MEASUREMENT_TIME_MS, powerPin,
+             -1, measurementsToAverage),
+      _useHeater(useHeater),
+      _i2c(theI2C) {}
+SensirionSHT3x::SensirionSHT3x(int8_t powerPin, bool useHeater,
+                               uint8_t measurementsToAverage)
+    : Sensor("SensirionSHT3x", SHT3X_NUM_VARIABLES, SHT3X_WARM_UP_TIME_MS,
+             SHT3X_STABILIZATION_TIME_MS, SHT3X_MEASUREMENT_TIME_MS, powerPin,
+             -1, measurementsToAverage, SHT3X_INC_CALC_VARIABLES),
+      _useHeater(useHeater),
+      _i2c(&Wire) {}
+// Destructor
+SensirionSHT3x::~SensirionSHT3x() {}
+
+
+String SensirionSHT3x::getSensorLocation(void) {
+    return F("I2C_0x44"); //Hardwired with SHT31_DEFAULT_ADDR
+}
+
+
+bool SensirionSHT3x::setup(void) {
+    _i2c->begin();  // Start the wire library (sensor power not required)
+
+    // Timeouts allow for any error on the wire to be handled
+    _i2c->setTimeout(20);
+
+    bool retVal =
+        Sensor::setup();  // this will set pin modes and the setup status bit
+
+    MS_DBG(getSensorNameAndLocation(), F(" setup:"),retVal);
+
+    // This sensor needs power for setup!
+    // The SHT3x's begin() does a soft reset to check for sensor communication.
+    bool wasOn = checkPowerOn();
+    if (!wasOn) { powerUp(); }
+    waitForWarmUp();
+
+    // Run begin fxn because it returns true or false for success in contact
+    uint8_t ntries  = 0;
+    bool    success = false;
+    while (!success && ntries < 5) {
+        success = sht3x_internal.begin();
+        ntries++;
+
+    }
+
+    sht3x_internal.heater(false);    
+
+    // Set status bits
+    if (!success) {
+        // Set the status error bit (bit 7)
+        _sensorStatus |= 0b10000000;
+        // UN-set the set-up bit (bit 0) since setup failed!
+        _sensorStatus &= 0b11111110;
+         MS_DBG(getSensorNameAndLocation(), F(" begin failed after tries "),ntries);
+    }
+    retVal &= success;
+
+    // Turn the power back off it it had been turned on
+    if (!wasOn) { powerDown(); }
+
+    return retVal;
+}
+
+
+bool SensirionSHT3x::addSingleMeasurementResult(void) {
+    // Initialize float variables
+    float temp_val  = -9999;
+    float humid_val = -9999;
+    bool  ret_val   = false;
+
+    // For *successfully*measurement started (status bit 6 set)
+    if (bitRead(_sensorStatus, 6)) {
+        MS_DBG(getSensorNameAndLocation(), F("is reporting:"));
+
+        #ifdef MS_SENSIRION_SHT3X_DEBUG 
+        // heater should be OFF - check if ON but only in debug when looking 
+        if (sht3x_internal.isHeaterEnabled()) {
+            sht3x_internal.heater(false);
+            MS_DBG(getSensorNameAndLocation(), F(" heater ERROR, was on "));
+        }
+        #endif //MS_SENSIRION_SHT3X_DEBUG 
+
+        ret_val  = sht3x_internal.readBoth(&temp_val,&humid_val);
+
+
+        if (!ret_val || isnan(temp_val)) temp_val = -9999;
+        if (!ret_val || isnan(humid_val)) humid_val = -9999;
+
+        MS_DBG(F("  Temp:"), temp_val, F("°C"));
+        MS_DBG(F("  Humidity:"), humid_val, '%');
+    } else {
+        MS_DBG(getSensorNameAndLocation(), F("is not currently measuring!"));
+    }
+
+    verifyAndAddMeasurementResult(SHT3X_TEMP_VAR_NUM, temp_val);
+    verifyAndAddMeasurementResult(SHT3X_HUMIDITY_VAR_NUM, humid_val);
+
+    // Unset the time stamp for the beginning of this measurement
+    _millisMeasurementRequested = 0;
+    // Unset the status bits for a measurement request (bits 5 & 6)
+    _sensorStatus &= 0b10011111;
+
+    return ret_val;
+}
+
+
+// The function to run the internal heater before going to sleep
+// Turning on heater **may** evaporate any moisture before next read
+bool SensirionSHT3x::sleep(void) {
+    if (!_useHeater) { return Sensor::sleep(); }
+
+    if (!checkPowerOn()) { return true; }
+    if (_millisSensorActivated == 0) {
+        MS_DBG(getSensorNameAndLocation(), F("was not measuring!"));
+        return true;
+    }
+
+    bool success = true;
+    MS_DBG(F("Running heater on"), getSensorNameAndLocation(),
+           F("at maximum for 1s to remove condensation."));
+
+
+    // Generate a short heat burst to possible evaporate any moisture
+    sht3x_internal.heater(true); 
+
+    #define HEATER_ON_TIME_MS 1000
+    unsigned long startMillis = millis();
+    do {
+        yield(); // running TinyUSB task
+    } while(millis() - startMillis < HEATER_ON_TIME_MS);
+
+    // Save power !!
+    sht3x_internal.heater(false);
+
+    if (success) {
+        // Unset the activation time
+        _millisSensorActivated = 0;
+        // Unset the measurement request time
+        _millisMeasurementRequested = 0;
+        // Unset the status bits for sensor activation (bits 3 & 4) and
+        // measurement request (bits 5 & 6)
+        _sensorStatus &= 0b10000111;
+        MS_DBG(F("Done"));
+    } else {
+        MS_DBG(getSensorNameAndLocation(),
+               F("did not successfully run the heater."));
+    }
+
+    return success;
+}