MCP9808 sensor implementation (#1188)

* MCP9808 Sensor Implementation Initial Test

platformio.ini

@@ -116,6 +116,7 @@ lib_deps =
   robtillaart/DS18B20@^0.1.11
   adafruit/Adafruit BME280 Library@^2.2.2
   adafruit/Adafruit BME680 Library@^2.0.1
+  adafruit/Adafruit MCP9808 Library@^2.0.0
   
 ; Common settings for ESP targes, mixin with extends = esp32_base
 [esp32_base]

src/plugins/EnvironmentalMeasurement/EnvironmentalMeasurementPlugin.cpp

@@ -14,11 +14,13 @@
 #include "Sensor/BME680Sensor.h"
 #include "Sensor/DHTSensor.h"
 #include "Sensor/DallasSensor.h"
+#include "Sensor/MCP9808Sensor.h"
 
 BME280Sensor bme280Sensor;
 BME680Sensor bme680Sensor;
 DHTSensor dhtSensor;
 DallasSensor dallasSensor;
+MCP9808Sensor mcp9808Sensor;
 
 #define FAILED_STATE_SENSOR_READ_MULTIPLIER 10
 #define DISPLAY_RECEIVEID_MEASUREMENTS_ON_SCREEN true
@@ -88,6 +90,8 @@ int32_t EnvironmentalMeasurementPlugin::runOnce()
                     return bme280Sensor.runOnce();
                 case RadioConfig_UserPreferences_EnvironmentalMeasurementSensorType_BME680:
                     return bme680Sensor.runOnce();
+                case RadioConfig_UserPreferences_EnvironmentalMeasurementSensorType_MCP9808:
+                    return mcp9808Sensor.runOnce();
                 default:
                     DEBUG_MSG("EnvironmentalMeasurement: Invalid sensor type selected; Disabling plugin");
                     return (INT32_MAX);
@@ -137,6 +141,8 @@ int32_t EnvironmentalMeasurementPlugin::runOnce()
                 case RadioConfig_UserPreferences_EnvironmentalMeasurementSensorType_BME280:
                 case RadioConfig_UserPreferences_EnvironmentalMeasurementSensorType_BME680:
                     return (BME_SENSOR_MINIMUM_WAIT_TIME_BETWEEN_READS);
+                case RadioConfig_UserPreferences_EnvironmentalMeasurementSensorType_MCP9808:
+                    return (MCP_SENSOR_MINIMUM_WAIT_TIME_BETWEEN_READS);
                 default:
                     return (DEFAULT_SENSOR_MINIMUM_WAIT_TIME_BETWEEN_READS);
             }
@@ -267,6 +273,9 @@ bool EnvironmentalMeasurementPlugin::sendOurEnvironmentalMeasurement(NodeNum des
         case RadioConfig_UserPreferences_EnvironmentalMeasurementSensorType_BME680:
             bme680Sensor.getMeasurement(&m);
             break;
+        case RadioConfig_UserPreferences_EnvironmentalMeasurementSensorType_MCP9808:
+            mcp9808Sensor.getMeasurement(&m);
+            break;
         default:
             DEBUG_MSG("EnvironmentalMeasurement: Invalid sensor type selected; Disabling plugin");
             return false;

src/plugins/EnvironmentalMeasurement/Sensor/MCP9808Sensor.cpp

@@ -0,0 +1,28 @@
+#include "../mesh/generated/environmental_measurement.pb.h"
+#include "configuration.h"
+#include "EnvironmentalMeasurementSensor.h"
+#include "MCP9808Sensor.h"
+#include <Adafruit_MCP9808.h>
+
+MCP9808Sensor::MCP9808Sensor() : EnvironmentalMeasurementSensor {} {
+}
+
+int32_t MCP9808Sensor::runOnce() {
+    unsigned mcp9808Status;
+    // Default i2c address for MCP9808
+    mcp9808Status = mcp9808.begin(0x18); 
+    if (!mcp9808Status) {
+        DEBUG_MSG("Could not find a valid MCP9808 sensor, check wiring, address, sensor ID!");
+    } else {
+        DEBUG_MSG("EnvironmentalMeasurement: Opened MCP9808 on default i2c bus");
+        // Reduce resolution from 0.0625 degrees (precision) to 0.125 degrees (high). 
+        mcp9808.setResolution(2);
+    }
+    return (MCP_SENSOR_MINIMUM_WAIT_TIME_BETWEEN_READS);
+}
+
+bool MCP9808Sensor::getMeasurement(EnvironmentalMeasurement *measurement) {
+    measurement->temperature = mcp9808.readTempC();
+
+    return true;
+}    

src/plugins/EnvironmentalMeasurement/Sensor/MCP9808Sensor.h

@@ -0,0 +1,15 @@
+#include "../mesh/generated/environmental_measurement.pb.h"
+#include "EnvironmentalMeasurementSensor.h"
+#include <Adafruit_MCP9808.h>
+
+#define MCP_SENSOR_MINIMUM_WAIT_TIME_BETWEEN_READS 1000
+
+class MCP9808Sensor : virtual public EnvironmentalMeasurementSensor {
+private:
+    Adafruit_MCP9808 mcp9808;
+
+public:
+    MCP9808Sensor();
+    virtual int32_t runOnce() override;
+    virtual bool getMeasurement(EnvironmentalMeasurement *measurement) override;
+};