Diff: main.cpp

Revision:

0:8a5d6b639e51

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Mon Feb 06 22:22:26 2017 +0000
@@ -0,0 +1,92 @@
+#include "mbed.h"
+ 
+#define THERMISTORNOMINAL 10000      
+#define TEMPERATURENOMINAL 25
+#define BCOEFFICIENT 3435
+//#define SERIESRESISTOR 10000
+#define SERIESRESISTOR 10000
+#define TEMPRATE 0.2
+#define NUMSAMPLES 100
+
+AnalogIn thermistor1(A0);
+AnalogIn thermistor2(A1);
+AnalogIn thermistor3(A2);
+AnalogIn thermistor4(A3);
+AnalogIn thermistor5(A4);
+AnalogIn thermistor6(A5);
+AnalogIn thermistor7(D11);
+ Serial pc(SERIAL_TX, SERIAL_RX);
+DigitalOut led(LED1);
+float tempArray[7];
+unsigned int samples[NUMSAMPLES];
+
+void readProbeX(int probeNum) {
+    float resistance = 0;
+    float average;
+    int i;
+    for (i=0; i< NUMSAMPLES; i++) {
+        switch (probeNum){
+            case 0:
+            samples[i] = thermistor1.read_u16();
+            break;
+            case 1:
+            samples[i] = thermistor2.read_u16();
+            break;
+             case 2:
+            samples[i] = thermistor3.read_u16();
+            break;
+             case 3:
+            samples[i] = thermistor4.read_u16();
+            break;
+             case 4:
+            samples[i] = thermistor5.read_u16();
+            break;
+             case 5:
+            samples[i] = thermistor6.read_u16();
+            break;
+            case 6:
+            resistance = thermistor7.read_u16();
+            break;
+            default:
+            break;
+                
+        }
+        wait(0.002);
+    }
+    // average all the samples out
+    average = 0;
+    for (i=0; i< NUMSAMPLES; i++) {
+        average += samples[i];
+    }
+    average /= NUMSAMPLES;
+    resistance = average;
+    resistance = (float) SERIESRESISTOR / ((65536 / resistance) - 1.0);
+    float steinhart;
+    steinhart = (log(resistance / THERMISTORNOMINAL))/BCOEFFICIENT + (1.0 / (TEMPERATURENOMINAL + 273.15));
+    steinhart = (1.0 / steinhart) - 273.15;   
+    tempArray[probeNum] = steinhart;    
+    //printf("read temp %d = %.1f C\n",probeNum,  tempArray[probeNum]);
+    //wait(0.5);
+}
+void init(){
+
+}
+int main() {
+    //printf("\nFermenter Temp Array\n");
+     //pc.printf("Hello World !\n");
+    while(1) {
+        int x;
+        for (x = 0;  x < 7; x++){
+            readProbeX(x);
+        }
+        for (x = 6;  x >= 0; x--){
+            printf("Temp Probe %d = %.1f C\n",x,  tempArray[x]);
+        }
+        //printf("%.1f,%.1f,%.1f,%.1f,%.1f,%.1f,%.1f\n", tempArray[0], tempArray[1], tempArray[2], tempArray[3], tempArray[4], tempArray[5], tempArray[6]);
+        pc.printf("\n");
+        wait(5.0);
+ 
+    }
+
+}
+