#include "mbed.h"

// Global constants
const double resistance = 100000; // 100K resistor, 99K read on meter
const int ratedCapacitance = 470;

// Global variables
DigitalOut source(p5);
DigitalInOut discharge(p6);
AnalogIn capacitor(p20);

// Global variables
bool charged;
float meter;
int runs;
int good;
int bad;

int main() {
    runs = 1;

    while (runs <= 10) {

        // reset counters
        good = 0;
        bad = 0;

        Timer t;            // init timer
        double capacitance; // create precision variable for capacitance

        // Turn off source
        source = 0;

        // Discharge capacitor
        discharge.output(); // configure discharge pin as output only
        discharge = 0;
        charged = 0;
        wait(1);

        // Reset timer
        t.reset();

        // Disable discharge pin
        discharge.input();          // reconfigure pin as input only
        discharge.mode(PullNone);   // configure with no internal pullup or pulldown

        printf("\n-----\n");
        printf("\nRun: %d\n", runs);  // display number of runs

        // Turn on source voltage
        // and start timer
        source = 1;
        t.start();

        // Continuously read capacitor until 63.2% charged
        while (charged != 1) {
            meter = capacitor.read();
            good++;
            if ( (meter >= 0.632) && (meter < 0.634) ) {
                charged = 1;
            } else if (meter > 0.634) {
                bad++;
                printf("* debug - bad meter value: %.3f *\t", meter);
                printf("reads: %d\t", good);
                printf("bad: %d\n", bad);
            }
        }

        t.stop();   // stop timer

        capacitance = t.read_us()/resistance;           // C will be uF, because time in seconds is in us
        printf("\n\nRated capacitance: %d uF\n", ratedCapacitance);
        printf("Last read: %.3f\n", meter);
        printf("Total reads: %d\t", good);
        printf("bad: %d\n", bad);
        printf("Micro-seconds: %d\n", t.read_us());
        printf("Charge resistor: %g\n", resistance);
        printf("Capacitance:\t%.1f uF\n", capacitance);  // output to terminal

        // Turn off source
        source = 0;

        // Discharge capacitor
        discharge.output();
        discharge = 0;
        wait(1);

        // increment run count
        runs++;
    }
    printf("\nAll done.\n");
}
// end main();