Support for BH1750 luminosity sensor

code/espurna/config/sensors.h

@@ -57,6 +57,7 @@
 #define SENSOR_MHZ19_ID                     0x14
 #define SENSOR_SI7021_ID                    0x15
 #define SENSOR_SHT3X_I2C_ID                 0x16
+#define SENSOR_BH1750_ID                    0x17
 
 //--------------------------------------------------------------------------------
 // Magnitudes
@@ -81,8 +82,9 @@
 #define MAGNITUDE_PM2dot5                   16
 #define MAGNITUDE_PM10                      17
 #define MAGNITUDE_CO2                       18
+#define MAGNITUDE_LUX                       19
 
-#define MAGNITUDE_MAX                       19
+#define MAGNITUDE_MAX                       20
 
 // =============================================================================
 // Specific data for each sensor
@@ -102,6 +104,27 @@
 #define ADC_VCC_ENABLED                 0
 #endif
 
+//------------------------------------------------------------------------------
+// BH1750
+// Enable support by passing BH1750_SUPPORT=1 build flag
+// http://www.elechouse.com/elechouse/images/product/Digital%20light%20Sensor/bh1750fvi-e.pdf
+//------------------------------------------------------------------------------
+
+#ifndef BH1750_SUPPORT
+#define BH1750_SUPPORT                  0
+#endif
+
+#ifndef BH1750_ADDRESS
+#define BH1750_ADDRESS                  0x00    // 0x00 means auto
+#endif
+
+#define BH1750_MODE                     BH1750_CONTINUOUS_HIGH_RES_MODE
+
+#if BH1750_SUPPORT
+#undef I2C_SUPPORT
+#define I2C_SUPPORT                     1
+#endif
+
 //------------------------------------------------------------------------------
 // BME280/BMP280
 // Enable support by passing BMX280_SUPPORT=1 build flag
@@ -415,7 +438,7 @@
 // Sensor helpers configuration
 // =============================================================================
 
-#if ANALOG_SUPPORT || BMX280_SUPPORT || DALLAS_SUPPORT \
+#if ANALOG_SUPPORT || BH1750_SUPPORT || BMX280_SUPPORT || DALLAS_SUPPORT \
     || DHT_SUPPORT || DIGITAL_SUPPORT || ECH1560_SUPPORT \
     || EMON_ADC121_SUPPORT || EMON_ADS1X15_SUPPORT \
     || EMON_ANALOG_SUPPORT || EVENTS_SUPPORT || HLW8012_SUPPORT \
@@ -474,7 +497,7 @@ PROGMEM const unsigned char magnitude_decimals[] = {
     3, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0,
     0, 0, 0,
-    0
+    0, 0
 };
 
 PROGMEM const char magnitude_unknown_topic[] = "unknown";
@@ -496,6 +519,7 @@ PROGMEM const char magnitude_analog_topic[] = "analog";
 PROGMEM const char magnitude_digital_topic[] = "digital";
 PROGMEM const char magnitude_events_topic[] = "events";
 PROGMEM const char magnitude_co2_topic[] = "co2";
+PROGMEM const char magnitude_lux_topic[] = "lux";
 
 PROGMEM const char* const magnitude_topics[] = {
     magnitude_unknown_topic, magnitude_temperature_topic, magnitude_humidity_topic,
@@ -504,7 +528,7 @@ PROGMEM const char* const magnitude_topics[] = {
     magnitude_power_factor_topic, magnitude_energy_topic, magnitude_energy_delta_topic,
     magnitude_pm1dot0_topic, magnitude_pm2dot5_topic, magnitude_pm10_topic,
     magnitude_analog_topic, magnitude_digital_topic, magnitude_events_topic,
-    magnitude_co2_topic
+    magnitude_co2_topic, magnitude_lux_topic
 };
 
 PROGMEM const char magnitude_empty[] = "";
@@ -518,6 +542,7 @@ PROGMEM const char magnitude_watts[] = "W";
 PROGMEM const char magnitude_joules[] = "J";
 PROGMEM const char magnitude_ugm3[] = "µg/m3";
 PROGMEM const char magnitude_ppm[] = "ppm";
+PROGMEM const char magnitude_lux[] = "lux";
 
 PROGMEM const char* const magnitude_units[] = {
     magnitude_empty, magnitude_celsius, magnitude_percentage,
@@ -526,7 +551,7 @@ PROGMEM const char* const magnitude_units[] = {
     magnitude_percentage, magnitude_joules, magnitude_joules,
     magnitude_ugm3, magnitude_ugm3, magnitude_ugm3,
     magnitude_empty, magnitude_empty, magnitude_empty,
-    magnitude_ppm
+    magnitude_ppm, magnitude_lux
 };
 
 #include "../sensors/BaseSensor.h"
@@ -535,6 +560,10 @@ PROGMEM const char* const magnitude_units[] = {
     #include "../sensors/AnalogSensor.h"
 #endif
 
+#if BH1750_SUPPORT
+    #include "../sensors/BH1750Sensor.h"
+#endif
+
 #if BMX280_SUPPORT
     #include <SparkFunBME280.h>
     #include "../sensors/BMX280Sensor.h"

code/espurna/sensor.ino

@@ -210,6 +210,15 @@ void _sensorInit() {
     }
     #endif
 
+    #if BH1750_SUPPORT
+    {
+        BH1750Sensor * sensor = new BH1750Sensor();
+        sensor->setAddress(BH1750_ADDRESS);
+        sensor->setMode(BH1750_MODE);
+        _sensors.push_back(sensor);
+    }
+    #endif
+
     #if BMX280_SUPPORT
     {
         BMX280Sensor * sensor = new BMX280Sensor();

code/espurna/sensors/BH1750Sensor.h

@@ -0,0 +1,155 @@
+// -----------------------------------------------------------------------------
+// BH1750 Liminosity sensor over I2C
+// Copyright (C) 2017 by Xose Pérez <xose dot perez at gmail dot com>
+// -----------------------------------------------------------------------------
+
+#if SENSOR_SUPPORT && BH1750_SUPPORT
+
+#pragma once
+
+#include "Arduino.h"
+#include "I2CSensor.h"
+#if I2C_USE_BRZO
+#include <brzo_i2c.h>
+#else
+#include <Wire.h>
+#endif
+
+#define BH1750_CONTINUOUS_HIGH_RES_MODE     0x10    // Start measurement at 1lx resolution. Measurement time is approx 120ms.
+#define BH1750_CONTINUOUS_HIGH_RES_MODE_2   0x11    // Start measurement at 0.5lx resolution. Measurement time is approx 120ms.
+#define BH1750_CONTINUOUS_LOW_RES_MODE      0x13    // Start measurement at 4lx resolution. Measurement time is approx 16ms.
+#define BH1750_ONE_TIME_HIGH_RES_MODE       0x20    // Start measurement at 1lx resolution. Measurement time is approx 120ms.
+                                                    // Device is automatically set to Power Down after measurement.
+#define BH1750_ONE_TIME_HIGH_RES_MODE_2     0x21    // Start measurement at 0.5lx resolution. Measurement time is approx 120ms.
+                                                    // Device is automatically set to Power Down after measurement.
+#define BH1750_ONE_TIME_LOW_RES_MODE        0x23    // Start measurement at 1lx resolution. Measurement time is approx 120ms.
+                                                    // Device is automatically set to Power Down after measurement.
+
+class BH1750Sensor : public I2CSensor {
+
+    public:
+
+        // ---------------------------------------------------------------------
+        // Public
+        // ---------------------------------------------------------------------
+
+        BH1750Sensor(): I2CSensor() {
+            _sensor_id = SENSOR_BH1750_ID;
+            _count = 1;
+        }
+
+        // ---------------------------------------------------------------------
+
+        void setMode(unsigned char mode) {
+            if (_mode == mode) return;
+            _mode = mode;
+            _dirty = true;
+        }
+
+        // ---------------------------------------------------------------------
+
+        unsigned char getMode() {
+            return _mode;
+        }
+
+        // ---------------------------------------------------------------------
+        // Sensor API
+        // ---------------------------------------------------------------------
+
+        // Initialization method, must be idempotent
+        void begin() {
+
+            if (!_dirty) return;
+            _dirty = false;
+
+            // I2C auto-discover
+            unsigned char addresses[] = {0x23, 0x5C};
+            _address = _begin_i2c(_address, sizeof(addresses), addresses);
+            if (_address == 0) return;
+
+            // Configure
+            _configure();
+            delay(10);
+
+        }
+
+        // Descriptive name of the sensor
+        String description() {
+            char buffer[25];
+            snprintf(buffer, sizeof(buffer), "BH1750 @ I2C (0x%02X)", _address);
+            return String(buffer);
+        }
+
+        // Type for slot # index
+        unsigned char type(unsigned char index) {
+            _error = SENSOR_ERROR_OK;
+            if (index == 0) return MAGNITUDE_LUX;
+            _error = SENSOR_ERROR_OUT_OF_RANGE;
+            return MAGNITUDE_NONE;
+        }
+
+        // Current value for slot # index
+        double value(unsigned char index) {
+            _error = SENSOR_ERROR_OK;
+            if (index == 0) return _read();
+            _error = SENSOR_ERROR_OUT_OF_RANGE;
+            return 0;
+        }
+
+    protected:
+
+        void _configure() {
+            #if I2C_USE_BRZO
+                uint8_t buffer[1] = {_mode};
+                brzo_i2c_start_transaction(_address, I2C_SCL_FREQUENCY);
+                brzo_i2c_write(buffer, 1, false);
+                brzo_i2c_end_transaction();
+            #else
+                Wire.beginTransmission(_address);
+                Wire.write(_mode);
+                Wire.endTransmission();
+            #endif
+        }
+
+        double _read() {
+
+            double level;
+            uint8_t buffer[2];
+
+            // For one-shot modes reconfigure sensor & wait for conversion
+            if (_mode & 0x20) {
+
+                _configure();
+
+                // According to datasheet
+                // conversion time is ~16ms for low resolution
+                // and ~120 for high resolution
+                // but more time is needed
+                unsigned long wait = (_mode & 0x02) ? 24 : 180;
+                unsigned long start = millis();
+                while (millis() - start < wait) delay(1);
+
+            }
+
+            #if I2C_USE_BRZO
+                brzo_i2c_start_transaction(_address, I2C_SCL_FREQUENCY);
+                brzo_i2c_read(buffer, 2, false);
+                brzo_i2c_end_transaction();
+            #else
+                Wire.beginTransmission(_address);
+                Wire.requestFrom(_address, (unsigned char) 2);
+                buffer[0] = Wire.read();
+                buffer[1] = Wire.read();
+                Wire.endTransmission();
+            #endif
+
+            level = buffer[0] * 256 + buffer[1];
+            return level / 1.2;
+
+        }
+
+        unsigned char _mode;
+
+};
+
+#endif // SENSOR_SUPPORT && SI7021_SUPPORT

code/html/custom.js

@@ -33,7 +33,7 @@ function sensorName(id) {
         "DHT", "Dallas", "Emon Analog", "Emon ADC121", "Emon ADS1X15",
         "HLW8012", "V9261F", "ECH1560", "Analog", "Digital",
         "Events", "PMSX003", "BMX280", "MHZ19", "SI7021",
-        "SHT3X I2C"
+        "SHT3X I2C", "BH1750"
     ];
     if (1 <= id && id <= names.length) return names[id-1];
     return null;
@@ -45,7 +45,7 @@ function magnitudeType(type) {
         "Current", "Voltage", "Active Power", "Apparent Power",
         "Reactive Power", "Power Factor", "Energy", "Energy (delta)",
         "Analog", "Digital", "Events",
-        "PM1.0", "PM2.5", "PM10", "CO2"
+        "PM1.0", "PM2.5", "PM10", "CO2", "Lux"
     ];
     if (1 <= type && type <= types.length) return types[type-1];
     return null;
@@ -54,7 +54,7 @@ function magnitudeType(type) {
 function magnitudeError(error) {
     var errors = [
         "OK", "Out of Range", "Warming Up", "Timeout", "Wrong ID",
-        "CRC Error", "I2C Error"
+        "CRC Error", "I2C Error", "GPIO Error"
     ];
     if (0 <= error && error < errors.length) return errors[error];
     return "Error " + error;