Diff: TemperatureController.cpp

Revision:

0:dab140a197e0

Child:

1:eb527bc93b62

diff -r 000000000000 -r dab140a197e0 TemperatureController.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TemperatureController.cpp	Fri Jun 03 14:24:25 2016 +0000
@@ -0,0 +1,60 @@
+#include "TemperatureController.h"
+
+#include "stdio.h"
+
+AnalogIn temperature_sensor(p20);
+
+TemperatureController::TemperatureController()
+{
+    printf("Initiate Temperature Controller\r\n");
+}
+
+// Function reads sensor values and averages N sensor values
+float TemperatureController::readSensor()
+{
+    float analogin_value;
+    float temperature;
+    
+    // Read 0-1.0 value
+    for(int i = 0; i < N; i++)
+    {
+        analogin_value += temperature_sensor.read();
+    }
+    // Average 10 sensor values
+    analogin_value /= (float) N;
+    
+    temperature = analoginToCelsius(analogin_value);
+    
+    return temperature;
+}
+
+// Function converts average sensor value to ppt
+float TemperatureController::analoginToCelsius(float analogin_value)
+{
+    float voltage;
+    float rt, logrt;
+    float temperature;
+    
+    // Convert average sensor value to value with range 0-5.0v
+    voltage = analogin_value * 3.3f * (5.0f/3.0f) + 0.45f;
+    
+    // Calcuate R_T
+    rt = (15000.0f * voltage) / (4.8f - voltage);
+    
+    logrt = log(rt);
+    temperature = 1.0 / (0.00102119 + (0.000222468 * logrt) + (0.000000133342 * logrt*logrt*logrt));
+    
+    temperature = temperature - 273.15;
+    
+    return temperature;
+}
+
+// Function prints temperature sensor value in celsius
+void TemperatureController::displayCelsius()
+{
+    float temperature;
+    
+    temperature = readSensor();
+    
+    printf("Temperature: %f Celsius\r\n", temperature);
+}
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