added SDS011 sensor support

code/espurna/config/sensors.h

@@ -430,6 +430,23 @@
 #define MHZ19_TX_PIN                    15
 #endif
 
+//------------------------------------------------------------------------------
+// SDS011 particulates sensor
+// Enable support by passing SDS011_SUPPORT=1 build flag
+//------------------------------------------------------------------------------
+
+#ifndef SDS011_SUPPORT
+#define SDS011_SUPPORT                   0
+#endif
+
+#ifndef SDS011_RX_PIN
+#define SDS011_RX_PIN                    14
+#endif
+
+#ifndef SDS011_TX_PIN
+#define SDS011_TX_PIN                    12
+#endif
+
 //------------------------------------------------------------------------------
 // NTC sensor
 // Enable support by passing NTC_SUPPORT=1 build flag
@@ -657,6 +674,7 @@
     GUVAS12SD_SUPPORT || \
     HLW8012_SUPPORT || \
     MHZ19_SUPPORT || \
+    SDS011_SUPPORT || \
     NTC_SUPPORT || \
     SENSEAIR_SUPPORT || \
     PMSX003_SUPPORT || \
@@ -785,6 +803,11 @@
     #include "../sensors/MHZ19Sensor.h"
 #endif
 
+#if SDS011_SUPPORT
+    #include <SoftwareSerial.h>
+    #include "../sensors/SDS011Sensor.h"
+#endif
+
 #if NTC_SUPPORT
     #include "../sensors/AnalogSensor.h"
     #include "../sensors/NTCSensor.h"

code/espurna/config/types.h

@@ -276,6 +276,7 @@
 #define SENSOR_SENSEAIR_ID          0x24
 #define SENSOR_GEIGER_ID            0x25
 #define SENSOR_NTC_ID               0x26
+#define SENSOR_SDS011_ID            0x27
 
 //--------------------------------------------------------------------------------
 // Magnitudes

code/espurna/sensor.ino

@@ -330,13 +330,13 @@ void _sensorLoad() {
 
      */
 
-     #if AM2320_SUPPORT
-     {
-         AM2320Sensor * sensor = new AM2320Sensor();
-         sensor->setAddress(AM2320_ADDRESS);
-         _sensors.push_back(sensor);
-     }
-     #endif
+    #if AM2320_SUPPORT
+    {
+     AM2320Sensor * sensor = new AM2320Sensor();
+     sensor->setAddress(AM2320_ADDRESS);
+     _sensors.push_back(sensor);
+    }
+    #endif
 
     #if ANALOG_SUPPORT
     {
@@ -522,6 +522,15 @@ void _sensorLoad() {
     }
     #endif
 
+    #if SDS011_SUPPORT
+    {
+        SDS011Sensor * sensor = new SDS011Sensor();
+        sensor->setRX(SDS011_RX_PIN);
+        sensor->setTX(SDS011_TX_PIN);
+        _sensors.push_back(sensor);
+    }
+    #endif
+
     #if NTC_SUPPORT
     {
         NTCSensor * sensor = new NTCSensor();

code/espurna/sensors/SDS011Sensor.h

@@ -0,0 +1,173 @@
+// -----------------------------------------------------------------------------
+// SDS011 particulates sensor
+// Based on: https://github.com/ricki-z/SDS011
+//
+// Uses SoftwareSerial library
+// Copyright (C) 2018 by Lucas Pleß <hello at lucas-pless dot com>
+// -----------------------------------------------------------------------------
+
+#if SENSOR_SUPPORT && SDS011_SUPPORT
+
+#pragma once
+
+#include "Arduino.h"
+#include "BaseSensor.h"
+#include <SoftwareSerial.h>
+
+
+class SDS011Sensor : public BaseSensor {
+
+    public:
+
+        // ---------------------------------------------------------------------
+        // Public
+        // ---------------------------------------------------------------------
+
+        SDS011Sensor(): BaseSensor() {
+            _count = 2;
+            _sensor_id = SENSOR_SDS011_ID;
+        }
+
+        ~SDS011Sensor() {
+            if (_serial) delete _serial;
+        }
+
+        // ---------------------------------------------------------------------
+
+        void setRX(unsigned char pin_rx) {
+            if (_pin_rx == pin_rx) return;
+            _pin_rx = pin_rx;
+            _dirty = true;
+        }
+
+        void setTX(unsigned char pin_tx) {
+            if (_pin_tx == pin_tx) return;
+            _pin_tx = pin_tx;
+            _dirty = true;
+        }
+
+        // ---------------------------------------------------------------------
+
+        unsigned char getRX() {
+            return _pin_rx;
+        }
+
+        unsigned char getTX() {
+            return _pin_tx;
+        }
+
+        // ---------------------------------------------------------------------
+        // Sensor API
+        // ---------------------------------------------------------------------
+
+        // Initialization method, must be idempotent
+        void begin() {
+
+            if (!_dirty) return;
+
+            if (_serial) delete _serial;
+
+            _serial = new SoftwareSerial(_pin_rx, _pin_tx);
+            _serial->begin(9600);
+
+            _ready = true;
+            _dirty = false;
+        }
+
+        // Descriptive name of the sensor
+        String description() {
+            char buffer[28];
+            snprintf(buffer, sizeof(buffer), "SDS011 @ SwSerial(%u,%u)", _pin_rx, _pin_tx);
+            return String(buffer);
+        }
+
+        // Descriptive name of the slot # index
+        String slot(unsigned char index) {
+            return description();
+        };
+
+        // Address of the sensor (it could be the GPIO or I2C address)
+        String address(unsigned char index) {
+            char buffer[6];
+            snprintf(buffer, sizeof(buffer), "%u:%u", _pin_rx, _pin_tx);
+            return String(buffer);
+        }
+
+        // Type for slot # index
+        unsigned char type(unsigned char index) {
+            if (index == 0) return MAGNITUDE_PM2dot5;
+            if (index == 1) return MAGNITUDE_PM10;
+            return MAGNITUDE_NONE;
+        }
+
+        void pre() {
+            _read();
+        }
+
+        // Current value for slot # index
+        double value(unsigned char index) {
+            if (index == 0) return _p2dot5;
+            if (index == 1) return _p10;
+            return 0;
+        }
+
+
+
+    protected:
+
+        // ---------------------------------------------------------------------
+        // Protected
+        // ---------------------------------------------------------------------
+
+        void _read() {
+            byte buffer;
+            int value;
+            int len = 0;
+            int pm10_serial = 0;
+            int pm25_serial = 0;
+            int checksum_is;
+            int checksum_ok = 0;
+
+            while ((_serial->available() > 0) && (_serial->available() >= (10-len))) {
+                buffer = _serial->read();
+                value = int(buffer);
+                switch (len) {
+                    case (0): if (value != 170) { len = -1; }; break;
+                    case (1): if (value != 192) { len = -1; }; break;
+                    case (2): pm25_serial = value; checksum_is = value; break;
+                    case (3): pm25_serial += (value << 8); checksum_is += value; break;
+                    case (4): pm10_serial = value; checksum_is += value; break;
+                    case (5): pm10_serial += (value << 8); checksum_is += value; break;
+                    case (6): checksum_is += value; break;
+                    case (7): checksum_is += value; break;
+                    case (8): if (value == (checksum_is % 256)) { checksum_ok = 1; } else { len = -1; }; break;
+                    case (9): if (value != 171) { len = -1; }; break;
+                }
+
+                len++;
+
+                if (len == 10) {
+                    if(checksum_ok == 1) {
+                        _p10 = (float)pm10_serial/10.0;
+                        _p2dot5 = (float)pm25_serial/10.0;
+                        len = 0; checksum_ok = 0; pm10_serial = 0.0; pm25_serial = 0.0; checksum_is = 0;
+                        _error = SENSOR_ERROR_OK;
+                    } else {
+                        _error = SENSOR_ERROR_CRC;
+                    }
+                }
+
+                yield();
+            }
+
+        }
+
+        double _p2dot5 = 0;
+        double _p10 = 0;
+        unsigned int _pin_rx;
+        unsigned int _pin_tx;
+        SoftwareSerial * _serial = NULL;
+
+};
+
+#endif // SENSOR_SUPPORT && SDS011_SUPPORT