Support for HC-SR04 ultrasonic sensor

code/espurna/config/sensors.h

@@ -110,6 +110,7 @@
 #define SENSOR_GUVAS12SD_ID                 0x20
 #define SENSOR_CSE7766_ID                   0x21
 #define SENSOR_TMP3X_ID                     0x22
+#define SENSOR_HCSR04_ID                    0x23
 
 //--------------------------------------------------------------------------------
 // Magnitudes
@@ -136,8 +137,9 @@
 #define MAGNITUDE_CO2                       18
 #define MAGNITUDE_LUX                       19
 #define MAGNITUDE_UV                        20
+#define MAGNITUDE_DISTANCE                  21
 
-#define MAGNITUDE_MAX                       21
+#define MAGNITUDE_MAX                       22
 
 // =============================================================================
 // Specific data for each sensor
@@ -390,6 +392,23 @@
 
 #define EVENTS_DEBOUNCE                 50      // Do not register events within less than 10 millis
 
+//------------------------------------------------------------------------------
+// HC-SR04
+// Enable support by passing HCSR04_SUPPORT=1 build flag
+//------------------------------------------------------------------------------
+
+#ifndef HCSR04_SUPPORT
+#define HCSR04_SUPPORT                  0
+#endif
+
+#ifndef HCSR04_TRIGGER
+#define HCSR04_TRIGGER                  12      // GPIO for the trigger pin (output)
+#endif
+
+#ifndef HCSR04_ECHO
+#define HCSR04_ECHO                     14      // GPIO for the echo pin (input)
+#endif
+
 //------------------------------------------------------------------------------
 // HLW8012 Energy monitor IC
 // Enable support by passing HLW8012_SUPPORT=1 build flag
@@ -601,7 +620,8 @@
     || EMON_ANALOG_SUPPORT || EVENTS_SUPPORT || HLW8012_SUPPORT \
     || MHZ19_SUPPORT || PMSX003_SUPPORT || SHT3X_I2C_SUPPORT \
     || SI7021_SUPPORT || V9261F_SUPPORT || AM2320_SUPPORT \
-    || GUVAS12SD_SUPPORT || CSE7766_SUPPORT || TMP3X_SUPPORT
+    || GUVAS12SD_SUPPORT || CSE7766_SUPPORT || TMP3X_SUPPORT \
+    || HCSR04_SUPPORT
 #define SENSOR_SUPPORT                      1
 #else
 #define SENSOR_SUPPORT                      0
@@ -657,7 +677,8 @@ PROGMEM const unsigned char magnitude_decimals[] = {
     3, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0,
     0, 0, 0,
-    0, 0
+    0, 0,
+    2, 3
 };
 
 PROGMEM const char magnitude_unknown_topic[] = "unknown";
@@ -681,6 +702,7 @@ PROGMEM const char magnitude_pm10_topic[] = "pm10";
 PROGMEM const char magnitude_co2_topic[] = "co2";
 PROGMEM const char magnitude_lux_topic[] = "lux";
 PROGMEM const char magnitude_uv_topic[] = "uv";
+PROGMEM const char magnitude_distance_topic[] = "distance";
 
 PROGMEM const char* const magnitude_topics[] = {
     magnitude_unknown_topic, magnitude_temperature_topic, magnitude_humidity_topic,
@@ -689,7 +711,8 @@ PROGMEM const char* const magnitude_topics[] = {
     magnitude_power_factor_topic, magnitude_energy_topic, magnitude_energy_delta_topic,
     magnitude_analog_topic, magnitude_digital_topic, magnitude_events_topic,
     magnitude_pm1dot0_topic, magnitude_pm2dot5_topic, magnitude_pm10_topic,
-    magnitude_co2_topic, magnitude_lux_topic, magnitude_uv_topic
+    magnitude_co2_topic, magnitude_lux_topic, magnitude_uv_topic,
+    magnitude_distance_topic
 };
 
 PROGMEM const char magnitude_empty[] = "";
@@ -707,6 +730,7 @@ PROGMEM const char magnitude_ugm3[] = "µg/m3";
 PROGMEM const char magnitude_ppm[] = "ppm";
 PROGMEM const char magnitude_lux[] = "lux";
 PROGMEM const char magnitude_uv[] = "uv";
+PROGMEM const char magnitude_distance[] = "m";
 
 PROGMEM const char* const magnitude_units[] = {
     magnitude_empty, magnitude_celsius, magnitude_percentage,
@@ -715,7 +739,8 @@ PROGMEM const char* const magnitude_units[] = {
     magnitude_percentage, magnitude_joules, magnitude_joules,
     magnitude_empty, magnitude_empty, magnitude_empty,
     magnitude_ugm3, magnitude_ugm3, magnitude_ugm3,
-    magnitude_ppm, magnitude_lux, magnitude_uv
+    magnitude_ppm, magnitude_lux, magnitude_uv,
+    magnitude_distance
 };
 
 #include "../sensors/BaseSensor.h"
@@ -778,6 +803,10 @@ PROGMEM const char* const magnitude_units[] = {
     #include "../sensors/GUVAS12SDSensor.h"
 #endif
 
+#if HCSR04_SUPPORT
+    #include "../sensors/HCSR04Sensor.h"
+#endif
+
 #if HLW8012_SUPPORT
     #include <HLW8012.h>
     #include "../sensors/HLW8012Sensor.h"

code/espurna/sensor.ino

@@ -426,6 +426,15 @@ void _sensorLoad() {
     }
     #endif
 
+    #if HCSR04_SUPPORT
+    {
+        HCSR04Sensor * sensor = new HCSR04Sensor();
+        sensor->setTrigger(HCSR04_TRIGGER);
+        sensor->setEcho(HCSR04_ECHO);
+        _sensors.push_back(sensor);
+    }
+    #endif
+
     #if HLW8012_SUPPORT
     {
         HLW8012Sensor * sensor = new HLW8012Sensor();

code/espurna/sensors/HCSR04Sensor.h

@@ -0,0 +1,119 @@
+// -----------------------------------------------------------------------------
+// HC-SR04 Ultrasonic sensor
+// Copyright (C) 2018 by Xose Pérez <xose dot perez at gmail dot com>
+// -----------------------------------------------------------------------------
+
+#if SENSOR_SUPPORT && HCSR04_SUPPORT
+
+#pragma once
+
+#include "Arduino.h"
+#include "BaseSensor.h"
+
+class HCSR04Sensor : public BaseSensor {
+
+    public:
+
+        // ---------------------------------------------------------------------
+        // Public
+        // ---------------------------------------------------------------------
+
+        HCSR04Sensor(): BaseSensor() {
+            _count = 1;
+            _sensor_id = SENSOR_HCSR04_ID;
+        }
+
+        // ---------------------------------------------------------------------
+
+        void setEcho(unsigned char echo) {
+            _echo = echo;
+        }
+
+        void setTrigger(unsigned char trigger) {
+            _trigger = trigger;
+        }
+
+        // ---------------------------------------------------------------------
+
+        unsigned char getEcho() {
+            return _echo;
+        }
+
+        unsigned char getTrigger() {
+            return _trigger;
+        }
+
+        // ---------------------------------------------------------------------
+        // Sensor API
+        // ---------------------------------------------------------------------
+
+        // Initialization method, must be idempotent
+        void begin() {
+            pinMode(_echo, INPUT);
+            pinMode(_trigger, OUTPUT);
+            digitalWrite(_trigger, LOW);
+            _ready = true;
+        }
+
+        // Descriptive name of the sensor
+        String description() {
+            char buffer[24];
+            snprintf(buffer, sizeof(buffer), "HCSR04 @ GPIO(%u, %u)", _trigger, _echo);
+            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) {
+            return String(_trigger);
+        }
+
+        // Type for slot # index
+        unsigned char type(unsigned char index) {
+            if (index == 0) return MAGNITUDE_DISTANCE;
+            return MAGNITUDE_NONE;
+        }
+
+        // Current value for slot # index
+        double value(unsigned char index) {
+
+            if (index == 0) {
+
+                // Trigger pulse
+                digitalWrite(_trigger, HIGH);
+                delayMicroseconds(10);
+                digitalWrite(_trigger, LOW);
+
+                // Wait for echo pulse low-high-low
+                while ( digitalRead(_echo) == 0 ) yield();
+                unsigned long start = micros();
+                while ( digitalRead(_echo) == 1 ) yield();
+                unsigned long travel_time = micros() - start;
+
+                // Assuming a speed of sound of 340m/s
+                // Dividing by 2 since it is a round trip
+                return 340.0 * (double) travel_time / 1000000.0 / 2;
+
+            }
+
+            return 0;
+
+        }
+
+
+    protected:
+
+        // ---------------------------------------------------------------------
+        // Protected
+        // ---------------------------------------------------------------------
+
+        unsigned char _trigger;
+        unsigned char _echo;
+
+};
+
+#endif // SENSOR_SUPPORT && HCSR04_SUPPORT

code/espurna/sensors/TMP3XSensor.h

@@ -28,10 +28,8 @@ class TMP3XSensor : public BaseSensor {
         }
 
         void setType(unsigned char type) {
-            if (type == _type) return;
             if (35 <= type && type <= 37) {
               _type = type;
-              _dirty = true;
             }
         }
 

code/html/custom.js

@@ -37,7 +37,8 @@ function sensorName(id) {
         "DHT", "Dallas", "Emon Analog", "Emon ADC121", "Emon ADS1X15",
         "HLW8012", "V9261F", "ECH1560", "Analog", "Digital",
         "Events", "PMSX003", "BMX280", "MHZ19", "SI7021",
-        "SHT3X I2C", "BH1750", "PZEM004T", "AM2320 I2C", "GUVAS12SD"
+        "SHT3X I2C", "BH1750", "PZEM004T", "AM2320 I2C", "GUVAS12SD",
+        "TMP3X", "HC-SR04"
     ];
     if (1 <= id && id <= names.length) {
         return names[id - 1];
@@ -51,7 +52,7 @@ 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", "Lux", "UV"
+        "PM1.0", "PM2.5", "PM10", "CO2", "Lux", "UV", "Distance"
     ];
     if (1 <= type && type <= types.length) {
         return types[type - 1];