/*
    Example that measures a GPIO pin on a Raspberry Pi using my GPIOCPP class.
    GPIOCPP version 0.09, march 18, 2017 COPYLEFT - Pieter Suurmond.

    To compile this example with GCC, use the '-std=c++11' option. For example:
        g++ -Wall -O2 -std=c++11 measure.cpp gpiocpp.cpp -o measure
    But you may also use the supplied Makefile: just type 'make'.

    Before running this executable, connect button between GPIO pin 17 and GND.
    No external pull-up/down resistor is necessary, an internal pull-up is set
    by software. Make sure the correct pin number and correct Pi model number
    are specified below! Play with the button after typing on the commandline:
        ./measure
    You should see zeros appearing while pressing it down, ones while leaving it
    released.
*/
#include <iostream>                                   // For cout.
#include <unistd.h>                                   // For usleep().
#include "gpiocpp.h"                                  // Our GPIOCPP class.

int main()
{
    const char buttonpin = 17;  // Broadcom GPIO17 as input pin. Using const or
                                // constexpr here compiles to faster code!
    try {
        // First argument is Pi model number: 1 (for ARMv6) or 2 (for ARMv7).
        // Second argument is pathname to mem-map: "/dev/mem" or "/dev/gpiomem".
        GPIOCPP gpio(2, "/dev/gpiomem");

        gpio.config_read(buttonpin);                  // Configure as input pin.
        gpio.config_pull(buttonpin, PULL::UP);        // Install pull-up R.

        std::cout << "Sampling GPIO" << (int)buttonpin
                  << " at 50 Hz for 16 seconds:\n";

        for (int t = 0; t < 16*50; t++) {
            usleep(20000);                            // 20 milliseconds.
            std::cout << gpio.readpin(buttonpin) << std::flush;
        }
        //gpio.config_pull(buttonpin, PULL::OFF);     // Remove pull resistor.
    }
    catch (const char* errtxt) {    // When something goes wrong the constructor
        std::cout << errtxt;        // throws an exception describing the error.
        return 1;
    }
    std::cout << "\nDone.\n";
    return 0;
}