File content as of revision 11:75328ab1acf4:

#include "Keypad.h"

extern Serial PC;

void Keypad::_cbRow0Rise()
{
    _checkIndex(0, _rows[0]);
}

void Keypad::_cbRow1Rise()
{
    _checkIndex(1, _rows[1]);
}

void Keypad::_cbRow2Rise()
{
    _checkIndex(2, _rows[2]);
}

void Keypad::_cbRow3Rise()
{
    _checkIndex(3, _rows[3]);
}

void
Keypad::_setupRiseTrigger
(
)
{
    if (_rows[0]) {
        _rows[0]->rise(callback(this, &Keypad::_cbRow0Rise));
    }

    if (_rows[1]) {
        _rows[1]->rise(callback(this, &Keypad::_cbRow1Rise));
    }

    if (_rows[2]) {
        _rows[2]->rise(callback(this, &Keypad::_cbRow2Rise));
    }

    if (_rows[3]) {
        _rows[3]->rise(callback(this, &Keypad::_cbRow3Rise));
    }
}


Keypad::Keypad
(PinName      r0
,PinName      r1
,PinName      r2
,PinName      r3
,PinName      c0
,PinName      c1
,PinName      c2
,PinName      c3
,int          debounce_ms
)
{
    PinName rPins[4] = {r0, r1, r2, r3};
    PinName cPins[4] = {c0, c1, c2, c3};

    for (int i = 0; i < 4; i++) {
        _rows[i] = NULL;
        _cols[i] = NULL;
    }
    
    _nRow = 0;
    for (int i = 0; i < 4; i++) {
        if (rPins[i] != NC) {
            // PullDown required, otherwise won't work on STM32F407, most likely not on other STM32 MCUs as well
            // Without PullDown, InterruptIn seems to float
            _rows[i] = new InterruptIn(rPins[i], PullDown);
            _nRow++;
        } else
            break;
    }
    _setupRiseTrigger();
    
    _nCol = 0;
    for (int i = 0; i < 4; i++) {
        if (cPins[i] != NC) {
            _cols[i] = new DigitalOut(cPins[i]);
            _nCol++;
        } else
            break;
    }

    _debounce = debounce_ms; 
}

Keypad::~Keypad
()
{
    for (int i = 0; i < 4; i++) {
        if (_rows[i] != 0)
            delete _rows[i];
    }

    for (int i = 0; i < 4; i++) {
        if (_cols[i] != 0)
            delete _cols[i];
    }
}

void
Keypad::start
(
)
{
    for (int i = 0; i < _nCol; i++)
        _cols[i]->write(1);
}

void
Keypad::stop
(
)
{
    for (int i = 0; i < _nCol; i++)
        _cols[i++]->write(0);
}

void
Keypad::attach
(uint32_t     (*fptr)(uint32_t index)
)
{
    _callback.attach(fptr);
}

void
Keypad::_checkIndex
(int          row
,InterruptIn *therow
)
{
    // Blocking waiting not allowed by mbed-os-5
    // Keypad seems to work fine without debounce
#ifdef THREAD_H
    //Thread::wait(_debounce);
#else
    //wait_ms(_debounce);
#endif

    if (therow->read() == 0)
        return;

    int c;
    for (c = 0; c < _nCol; c++) {
        _cols[c]->write(0); // de-energize the column
        if (therow->read() == 0) {
            break;
        }
    }
    
    int index = row * _nCol + c;
    _callback.call(index);
    start(); // Re-energize all columns
}