counter.cpp

/*
Moura's Keyboard Scanner: turn you broken (or unused) keyboard in a MIDI controller
Copyright (C) 2017 Daniel Moura <oxesoft@gmail.com>

This code is originally hosted at https://github.com/oxesoft/keyboardscanner

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

/*
For reference, I've got these results at the time that I tested it for 61 keys and random pin mapping:
 426 Hz using standard digitalWrite/digitalRead
 896 Hz using DIO2 digitalWrite2/digitalRead2
1185 Hz using DIO2 digitalWrite2/digitalRead2 with static variables
*/

#include "globals.h"

void counterSetup()
{
}

void counterLoop()
{
    static unsigned long cycles = 0;
    static unsigned long start = 0;
    static unsigned long current = 0;
    cycles++;
    current = micros();
    if (current - start >= 1000000)
    {
        Serial.println(cycles);
        cycles = 0;
        start = current;
    }
}