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lptnote.cpp

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// $Id

//**********************************************************************
//                                                                     *
//    Description:   Implementation using PC LPT port to ring a bell   *
//                   for a single note.                                *
//                                                                     *
//    Author:        Chris White (whitecf@bcs.org.uk)                  *
//                                                                     *
//    Copyright (C) 2003  Monitor Computing Services Ltd.              *
//                                                                     *
//    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 2   *
//    of the License, or 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 (http://www.gnu.org/copyleft/gpl.html) along with this   *
//    program; if not, write to:                                       *
//       The Free Software Foundation Inc.,                            *
//       59 Temple Place - Suite 330,                                  *
//       Boston, MA  02111-1307,                                       *
//       USA.                                                          *
//                                                                     *
//**********************************************************************
//                                                                     *
//    Notes:                                                           *
//                                                                     *
//**********************************************************************

#include <dos.h>

#include <callback.h>
#include <mytrace.h>
#include <timeout.h>

#include "lptnote.h"



namespace Ut = Monitor::Utility;



int    LptNote::busy = 0;


LptNote::LptNote(int    newPortNumber, int    newPortBit)
{
    _USEMYTRACE_("LptNote::LptNote(newPortNumber, newPortBit)")


    unsigned int    *lptPortTable((unsigned int*)0x408);

    lptPort = *(lptPortTable + (--newPortNumber));

    originalControlPort         = inportb(lptPort + 0x002);
    originalExtendedControlPort = inportb(lptPort + 0x402);


    outportb(lptPort, 0);

    // Ensure port is operating in SPP mode
    if (0x3BC != lptPort)
    {
        outportb((lptPort + 0x402), 0);
    }
    outportb((lptPort + 0x002), 0);


    bitOn  = 1 << newPortBit;
    bitOff = ~bitOn;
}



LptNote::~LptNote()
{
    _USEMYTRACE_("LptNote::~LptNote()")

    outportb(lptPort, 0);

    // Restore port mode
    outportb((lptPort + 0x002), originalControlPort);
    if (0x3BC != lptPort)
    {
        outportb((lptPort + 0x402), originalExtendedControlPort);
    }
}



void
LptNote::sound() const
throw (Ut::Note::Busy)
{
    _USEMYTRACE_("LptNote::sound()")

    if (busy)
    {
        throw Ut::Note::Busy();
    }
    else
    {
        busy = !0;

        // Turn on output bit
        outportb(lptPort, (bitOn | inportb(lptPort)));

        // Time length of energisation of bell
        new Ut::Timeout(Ut::ConstCallback< LptNote >(*this,
                                                     &LptNote::switchOff),
                        1,
                        "energisation time");
    }
}



void
LptNote::switchOff() const
{
    _USEMYTRACE_("LptNote::switchOff()")

    // Turn off output bit
    outportb(lptPort, (bitOff & inportb(lptPort)));

    busy = 0;
}

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