main.cpp

00001 #include "mbed.h"
00002 
00003 //Constants
00004 #define N 10
00005 
00006 //Function Prototype
00007 float updateAverage(float newSample, float buffer[]);
00008 
00009 //Global objects
00010 Serial pc(USBTX, USBRX);
00011 
00012 BusOut binaryOutput(D5, D6, D7);
00013 AnalogIn POT_ADC_In(A0);
00014 AnalogIn LDR_ADC_In(A1);
00015 
00016 float xPOT[N]; //Aray of potentiometer samples
00017 float xLDR[N]; //Aray of LDR samples
00018 
00019 //Main function
00020 int main()
00021 {
00022 
00023     //Set baud rate to 115200
00024     pc.baud(115200);
00025 
00026     //Print header
00027     pc.printf("POT,LDR,avPOT, acLDR\n\n");
00028 
00029     while(1) {
00030 
00031         //Move the samples in both arrays to the right
00032         for (unsigned int n=(N-1); n>0; n--) {
00033             xPOT[n] = xPOT[n-1];
00034             xLDR[n] = xLDR[n-1];
00035         }
00036 
00037         //Insert the new sample at position 0
00038         xPOT[0] = POT_ADC_In;
00039         xLDR[0] = LDR_ADC_In;
00040 
00041         //Calculate average for POT
00042         float fSum = 0.0;
00043         for (unsigned int n=0; n<N; n++) {
00044             fSum += xPOT[n];
00045         }
00046         float fPOTAverage = fSum / (float)N;
00047 
00048         //Calculate average for LDR
00049         fSum = 0.0;
00050         for (unsigned int n=0; n<N; n++) {
00051             fSum += xLDR[n];
00052         }
00053         float fLDRAverage = fSum / (float)N;
00054 
00055         //Write to terminal via Serial interface
00056         pc.printf("%6.4f,%6.4f,%6.4f,%6.4f\n", xPOT[N/2], xLDR[N/2], fPOTAverage, fLDRAverage);
00057 
00058         //Check the threshold
00059         if (fLDRAverage > fPOTAverage) {
00060             binaryOutput = 0;   //Binary 000
00061         } else {
00062             binaryOutput = 7;   //Binary 111
00063         }
00064 
00065         //Wait 1/100th second
00066         wait(0.01);
00067 
00068 
00069     } //end while(1)
00070 } //end main
00071 
00072 
00073 /*
00074     First version of the updateAverage function
00075     TODO
00076 */
00077 float updateAverage(float newSample, float buffer[])
00078 {
00079     //Local variable - remember to initialise!
00080     float average = 0.0;
00081     
00082     //TODO: Move all samples to the right
00083  
00084     
00085     //TODO: Insert new sample
00086 
00087     
00088     //TODO: Calculate average
00089     
00090     //Return the result
00091     return average;
00092 }