Added DS18B20 Tempertur measurement

include/controller.h

@@ -11,7 +11,9 @@
 #ifndef FANLEDCTL_PINS
 #define FANLEDCTL_PINS
 
-#define FAN_PIN 12
-#define SIGNAL_PIN 13
+#define FAN_PIN     12  /**< Output Pin, controlling FAN speed via PWM */
+#define SIGNAL_PIN  13  /**< Input Pin, reading current FANs RPM*/
+
+#define GPIO_DS18B20    D7  /**< One-Wire used for Dallas temperature sensor */
 
 #endif /* End FANLEDCTL_PINS */

platformio.ini

@@ -12,3 +12,6 @@
 platform = espressif8266
 board = d1_wroom_02
 framework = arduino
+
+lib_deps = OneWire
+           DallasTemperature

src/main.cpp

@@ -1,11 +1,19 @@
 #include <Arduino.h>
+#include <DallasTemperature.h>
+#include <OneWire.h>
 #include "controller.h"
 
 
-#define DELAY_TIME 10000 // time between measurements [ms]
-#define MIN_FAN_SPEED_PERCENT 24 // minimum fan speed [%]
-#define MIN_TEMP 25 // turn fan off below [deg C]
-#define MAX_TEMP 40 // turn fan to full speed above [deg C]
+#define DELAY_TIME            10000 /**< time between measurements [ms] */
+#define MIN_FAN_SPEED_PERCENT 24 /**< minimum fan speed [%] */
+#define MIN_TEMP              25 /**< turn fan off below [deg C] */
+#define MAX_TEMP              40 /**< turn fan to full speed above [deg C] */
+#define INVALID_TEMP          (MAX_TEMP+MAX_TEMP) /**< Invalid temperature (on sensor failures)*/
+
+#define TEMP_SENSOR_MEASURE_SERIES  5 /**< Maximum resets */
+
+OneWire oneWire(GPIO_DS18B20);
+DallasTemperature sensors(&oneWire);
 
 /**
  * @brief Called once at start
@@ -14,9 +22,17 @@
 void setup() {
 
   Serial.begin(115200);
-
+  /* Setup FAN Control */
   pinMode(FAN_PIN, OUTPUT);
   pinMode(SIGNAL_PIN, INPUT);
+  /* Initialize Temperature sensor */
+  sensors.begin();
+  for(int j=0; j < TEMP_SENSOR_MEASURE_SERIES && sensors.getDeviceCount() == 0; j++)
+  {
+    delay(100);
+    sensors.begin();
+    Serial.println("Reset 1-Wire Bus");
+  }
 }
 
 /**
@@ -45,12 +61,28 @@ void setFanSpeedPercent(int p) {
   analogWrite(FAN_PIN, value);
 }
 
+float readTemperature(void)
+{
+  int sensorCount = sensors.getDeviceCount();
+  if (sensorCount > 0)
+  {
+    sensors.requestTemperatures();
+    float temp1Raw = sensors.getTempCByIndex(0);
+    if (temp1Raw > 0)
+    {
+      return temp1Raw;
+    }
+  }
+
+  return INVALID_TEMP;
+}
+
 /**
  * @brief Endless loop
  * (is called as fast as possible)
  */
 void loop() {
-  float temp = /* FIXME bme.readTemperature(); */ 
+  float temp = readTemperature();
   Serial.print("Temperature is ");
   Serial.print(temp);
   Serial.println(" deg C");