Task 4.3.4 Solution
main.cpp
- Committer:
- noutram
- Date:
- 2017-07-13
- Revision:
- 1:3c9ba9318ede
- Parent:
- 0:6a8980b23272
File content as of revision 1:3c9ba9318ede:
#include "mbed.h"
//Constants
#define N 10
//Function Prototype
float updateAverage(float newSample, float buffer[]);
//Global objects
Serial pc(USBTX, USBRX);
BusOut binaryOutput(D5, D6, D7);
AnalogIn POT_ADC_In(A0);
AnalogIn LDR_ADC_In(A1);
float xPOT[N]; //Aray of potentiometer samples
float xLDR[N]; //Aray of LDR samples
//Main function
int main()
{
//Set baud rate to 115200
pc.baud(115200);
//Print header
pc.printf("POT,LDR,avPOT, acLDR\n\n");
while(1) {
//Calculate averages
float fPOTAverage = updateAverage(POT_ADC_In, xPOT);
float fLDRAverage = updateAverage(LDR_ADC_In, xLDR);
//Write to terminal via Serial interface
pc.printf("%6.4f,%6.4f,%6.4f,%6.4f\n", xPOT[N/2], xLDR[N/2], fPOTAverage, fLDRAverage);
//Check the threshold
if (fLDRAverage > fPOTAverage) {
binaryOutput = 0; //Binary 000
} else {
binaryOutput = 7; //Binary 111
}
//Wait 1/100th second
wait(0.01);
} //end while(1)
} //end main
/** Update and calculate the average. This has not been "hand optimised" yet
*
* @param newSample The new sample to be added to the buffer
* @param buffer[] The array used to store N samples
* @returns
* average of the samples in the array buffer
*/
float updateAverage(float newSample, float buffer[])
{
//Local variable - remember to initialise!
float average = 0.0;
//Move all samples to the right
for (unsigned int n=(N-1); n>0; n--) {
buffer[n] = buffer[n-1];
}
//Insert new sample
buffer[0] = newSample;
//Calculate average
for (unsigned int n=0; n<N; n++) {
average += buffer[n];
}
average /= (float)N;
//Return the result
return average;
}
Nicholas Outram