IrWidget.cpp

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#include "IrSignal.h"
#include "Board.h" // for HAS_INPUT_CAPTURE
 
#if HAS_INPUT_CAPTURE
 
/* IR Widget: capture a raw IR signal and dump the timing of the non-demodulated signal
 
http://www.piclist.com/images/boards/irwidget/index.htm
http://www.hifi-remote.com/forums/dload.php?action=file&file_id=2044
http://www.hifi-remote.com/wiki/index.php?title=IR_Scope_and_IR_Widget_User%27s_Guide
http://www.compendiumarcana.com/irwidget/
 
Arduino digital pin numbers for the input capture pin (ICP) and the logic analyzer debugging pin (LA Dbg):
Board name / MCU                           | ICP pin                  | LA Dbg pin
-------------------------------------------|--------------.-----------|------------------------
Duemilanove/Uno (ATmega328P / ATmega168)   | ICP1/PB0, Arduino pin 8  | PD6, Arduino pin 6
Leonardo (ATmega32U4)                      | ICP1/PD4, Arduino pin 4  | PD6, Arduino pin 12
Arduino Mega 2560 (ATmega2560)             | ICP4/PL0, Arduino pin 49 | PL6, Arduino pin 43
 
see also here:
http://arduino.cc/en/Hacking/PinMapping168 (also for ATmega328P)
http://arduino.cc/en/Hacking/PinMapping32u4
http://arduino.cc/en/Hacking/PinMapping2560
 */
 
// Copyright (c) 2012 Michael Dreher  <michael(at)5dot1.de>
// this code may be distributed under the terms of the General Public License V2 (GPL V2)
// NOTE(BM) Michael agrees to "or later", see
// http://www.hifi-remote.com/forums/viewtopic.php?p=112586#112586
 
// Code slighty reorganized by Bengt Martensson
 
#include "IrWidget.h"
 
IrWidget::IrWidget(size_t captureLength,
        bool pullup,
        int16_t markExcess,
        milliseconds_t beginningTimeout,
        milliseconds_t endingTimeout) : IrReader(captureLength) {
    setup(pullup);
    captureData = new microseconds_t[bufferSize];
    setMarkExcess(markExcess);
    setBeginningTimeout(beginningTimeout);
    //endingTimeout = _BV(RANGE_EXTENSION_BITS) - 1;
    setEndingTimeout(endingTimeout);
 
    // Test that allocated memory is indeed usable. Otherwise crash will occur.
    for (unsigned int i = 0; i < bufferSize; i++)
        captureData[i] = 0;
}
 
IrWidget::~IrWidget() {
    delete[] captureData;
}
 
void IrWidget::setEndingTimeout(milliseconds_t timeOut) {
    endingTimeout = (ovlBitsDataType) ((timeOut/* /1000*/ + 16)/32);
}
 
milliseconds_t IrWidget::getEndingTimeout() const {
    //return (uint16_t) (timerValueToNanoSeconds((((uint32_t) endingTimeout)*CAPTURE_PRESCALER_FACTOR)) / 1000);
    return (uint16_t) 1000 * (endingTimeout << 15);
}
 
void IrWidget::dump(Stream &stream) const {
    bool printedSomething = IrSignal::dumpFrequency(stream, getFrequency());
    if (printedSomething)
        stream.print(' ');
    IrReader::dump(stream);
}
 
// Initialization
 
// initialize Timer and IO pins, needs to be called once
void IrWidget::setup(bool pullup) {
#ifdef ARDUINO
    // configure signal capture ICP pin as input
    cbi(CAT2(DDR, CAP_PORT), CAP_PIN);
    if (pullup)
        sbi(CAT2(PORT, CAP_PORT), CAP_PIN); // enable the internal 10k pull-up resistor
 
#if defined(DEBUG_PIN) && defined(DEBUG_PORT)
    sbi(CAT2(DDR, DEBUG_PORT), DEBUG_PIN); // configure logic analyzer debug pin as output
#endif
 
    // init timer, disable power save mode of timer
#ifdef PRR0 // for ATmega32U4 and ATmega2560
#if PRTIM <= 2
    cbi(PRR0, CAT2(PRTIM, CAP_TIM)); // for ATmega32U4 and ATmega2560
#else
    cbi(PRR1, CAT2(PRTIM, CAP_TIM)); // for ATmega2560
#endif
#else
    cbi(PRR, CAT2(PRTIM, CAP_TIM));
#endif
 
    CAT3(TCCR, CAP_TIM, A) = 0; // Timer mode 0 = normal
    CAT3(TCCR, CAP_TIM, B) = _BV(CAT2(ICNC, CAP_TIM)) | CAPTURE_PRESCALER_SETTING; // prescaler according to setting, enable noise canceler
#else
    std::cout << "pinMode(CAPTURE_PIN_1, " << (pullup ? "INPUT_PULLUP)" : "INPUT)") << std::endl;
#endif
}
 
#endif