#include "ntvdm.h"
#include <debug.h>
#include "speaker.h"
#include "hardware/pit.h"
#include <ndk/iofuncs.h>
#include <ndk/obfuncs.h>
#include <ntddbeep.h>

Include dependency graph for speaker.c:

Macros
#define	NDEBUG

#define	SPEAKER_RESPONSE 200

#define	MIN_AUDIBLE_FREQ 20

#define	MAX_AUDIBLE_FREQ 20000

#define	CLICK_FREQ 100

#define	UABS(x) (ULONG)((LONG)(x) < 0 ? -(LONG)(x) : (x))

Functions
static VOID	MakeBeep (ULONG Frequency, ULONG Duration)

static VOID	PulseSample (VOID)

VOID	SpeakerChange (UCHAR Port61hValue)

VOID	SpeakerInitialize (VOID)

VOID	SpeakerCleanup (VOID)

Variables
static HANDLE	hBeep = NULL

static LARGE_INTEGER	FreqCount

static LARGE_INTEGER	CountStart

static ULONG	PulseTickCount = 0

static ULONG	FreqPulses = 0

Macro Definition Documentation

◆ CLICK_FREQ

#define CLICK_FREQ 100

Definition at line 37 of file speaker.c.

◆ MAX_AUDIBLE_FREQ

#define MAX_AUDIBLE_FREQ 20000

Definition at line 36 of file speaker.c.

◆ MIN_AUDIBLE_FREQ

#define MIN_AUDIBLE_FREQ 20

Definition at line 35 of file speaker.c.

◆ NDEBUG

#define NDEBUG

Definition at line 13 of file speaker.c.

◆ SPEAKER_RESPONSE

#define SPEAKER_RESPONSE 200

Definition at line 33 of file speaker.c.

◆ UABS

#define UABS ( x ) (ULONG)((LONG)(x) < 0 ? -(LONG)(x) : (x))

Function Documentation

◆ MakeBeep()

static VOID MakeBeep	(	ULONG	Frequency,
		ULONG	Duration
	)

static

Definition at line 44 of file speaker.c.

{
    static ULONG LastFrequency = 0, LastDuration = 0;
 
    IO_STATUS_BLOCK IoStatusBlock;
    BEEP_SET_PARAMETERS BeepSetParameters;
 
    /* A null frequency means we stop beeping */
    if (Frequency == 0) Duration = 0;
 
    /*
     * Do nothing if we are replaying exactly the same sound
     * (this avoids hiccups due to redoing the same beeps).
     */
    if (Frequency == LastFrequency && Duration == LastDuration) return;
 
    /*
     * For small durations we automatically reset the beep so
     * that we can replay short beeps like clicks immediately.
     */
    if (Duration < 10)
    {
        LastFrequency = 0;
        LastDuration  = 0;
    }
    else
    {
        LastFrequency = Frequency;
        LastDuration  = Duration;
    }
 
    /* Set the data and do the beep */
    BeepSetParameters.Frequency = Frequency;
    BeepSetParameters.Duration  = Duration;
 
    NtDeviceIoControlFile(hBeep,
                          NULL,
                          NULL,
                          NULL,
                          &IoStatusBlock,
                          IOCTL_BEEP_SET,
                          &BeepSetParameters,
                          sizeof(BeepSetParameters),
                          NULL,
                          0);
}

Referenced by SpeakerChange().

◆ PulseSample()

static VOID PulseSample ( VOID )

static

Definition at line 93 of file speaker.c.

{
    static ULONG Pulses = 0, CountStartTick = 0, LastPulsesFreq = 0;
    ULONG LastPulseTickCount, CurrPulsesFreq;
    LARGE_INTEGER Counter;
    LONGLONG Elapsed;
 
    /*
     * Check how far away was the previous pulse and
     * if it was >= 200ms away then restart counting.
     */
    LastPulseTickCount = PulseTickCount;
    PulseTickCount     = GetTickCount();
    if (PulseTickCount - LastPulseTickCount >= SPEAKER_RESPONSE)
    {
        CountStart.QuadPart = 0;
        Pulses     = 0;
        FreqPulses = 0;
        return;
    }
 
    /* We have closely spaced pulses. Start counting. */
    if (CountStart.QuadPart == 0)
    {
        NtQueryPerformanceCounter(&CountStart, NULL);
        CountStartTick = PulseTickCount;
        Pulses     = 0;
        FreqPulses = 0;
        return;
    }
 
    /* A pulse is ongoing */
    ++Pulses;
 
    /* We require some pulses to have some statistics */
    if (PulseTickCount - CountStartTick <= (SPEAKER_RESPONSE >> 1)) return;
 
    /* Get count time */
    NtQueryPerformanceCounter(&Counter, NULL);
 
    /*
     * Get the number of speaker hundreds of microseconds that have passed
     * since we started counting.
     */
    Elapsed = (Counter.QuadPart - CountStart.QuadPart) * 10000 / FreqCount.QuadPart;
    if (Elapsed == 0) ++Elapsed;
 
    /* Update counting for next pulses */
    CountStart     = Counter;
    CountStartTick = PulseTickCount;
 
    // HACKHACK!! I need to check why we need to double the number
    // of pulses in order to have the correct frequency...
    Pulses <<= 1;
 
    /* Get the current pulses frequency */
    CurrPulsesFreq = 10000 * Pulses / Elapsed;
 
    /* Round the current pulses frequency up and align */
    if ((CurrPulsesFreq & 0x0F) > 7) CurrPulsesFreq += 0x10;
    CurrPulsesFreq &= ~0x0F;
 
    /* Reinitialize frequency counters if necessary */
    if (LastPulsesFreq == 0) LastPulsesFreq = CurrPulsesFreq;
    if (FreqPulses     == 0) FreqPulses     = LastPulsesFreq;
 
    /* Fix up the current pulses frequency if needed */
    if (LastPulsesFreq != 0 && CurrPulsesFreq == 0)
        CurrPulsesFreq = LastPulsesFreq;
 
    /*
     * Magic begins there...
     */
#define UABS(x) (ULONG)((LONG)(x) < 0 ? -(LONG)(x) : (x))
    if (UABS(CurrPulsesFreq - LastPulsesFreq) > 7)
    {
        /*
         * This can be a "large" fluctuation so ignore it for now, but take
         * it into account if it happens to be a real frequency change.
         */
        CurrPulsesFreq = (CurrPulsesFreq + LastPulsesFreq) >> 1;
    }
    else
    {
        // FreqPulses = ((FreqPulses << 2) + LastPulsesFreq + CurrPulsesFreq) / 6;
        FreqPulses = ((FreqPulses << 1) + LastPulsesFreq + CurrPulsesFreq) >> 2;
    }
 
    /* Round the pulses frequency up and align */
    if ((FreqPulses & 0x0F) > 7) FreqPulses += 0x10;
    FreqPulses &= ~0x0F;
 
    DPRINT("FreqPulses = %d, LastPulsesFreq = %d, CurrPulsesFreq = %d, Pulses = %d, Elapsed = %d\n",
           FreqPulses, LastPulsesFreq, CurrPulsesFreq, Pulses, Elapsed);
 
    LastPulsesFreq = CurrPulsesFreq;
    Pulses = 0;
}

Referenced by SpeakerChange().

◆ SpeakerChange()

VOID SpeakerChange ( UCHAR Port61hValue )

Definition at line 196 of file speaker.c.

{
    static BOOLEAN OldSpeakerOff = TRUE;
 
    BOOLEAN Timer2Gate = !!(Port61hValue & 0x01);
    BOOLEAN SpeakerOn  = !!(Port61hValue & 0x02);
 
    DPRINT("SpeakerChange -- Timer2Gate == %s ; SpeakerOn == %s\n",
           Timer2Gate ? "true" : "false", SpeakerOn ? "true" : "false");
 
    if (Timer2Gate)
    {
        if (SpeakerOn)
        {
            /* Start beeping */
            ULONG Frequency = (PIT_BASE_FREQUENCY / PitGetReloadValue(2));
            if (Frequency < MIN_AUDIBLE_FREQ || MAX_AUDIBLE_FREQ < Frequency)
                Frequency = 0;
 
            MakeBeep(Frequency, INFINITE);
        }
        else
        {
            /* Stop beeping */
            MakeBeep(0, 0);
        }
    }
    else
    {
        if (SpeakerOn)
        {
            if (OldSpeakerOff)
            {
                OldSpeakerOff = FALSE;
                PulseSample();
            }
 
            if (FreqPulses >= MIN_AUDIBLE_FREQ)
                MakeBeep(FreqPulses, INFINITE);
            else if (CountStart.QuadPart != 0)
                MakeBeep(CLICK_FREQ, 1); /* Click */
            else
                MakeBeep(0, 0);          /* Stop beeping */
        }
        else
        {
            OldSpeakerOff = TRUE;
 
            /*
             * Check how far away was the previous pulse and if
             * it was >= (200 + eps) ms away then stop beeping.
             */
            if (GetTickCount() - PulseTickCount >= SPEAKER_RESPONSE + (SPEAKER_RESPONSE >> 3))
            {
                CountStart.QuadPart = 0;
                FreqPulses = 0;
 
                /* Stop beeping */
                MakeBeep(0, 0);
            }
        }
    }
}

Referenced by PitChan2Out(), and Port61hWrite().

◆ SpeakerCleanup()

VOID SpeakerCleanup ( VOID )

Definition at line 295 of file speaker.c.

{
    NtClose(hBeep);
}

Referenced by EmulatorCleanup().

◆ SpeakerInitialize()

VOID SpeakerInitialize ( VOID )

Definition at line 260 of file speaker.c.

{
    NTSTATUS Status;
    UNICODE_STRING BeepDevice;
    OBJECT_ATTRIBUTES ObjectAttributes;
    IO_STATUS_BLOCK IoStatusBlock;
 
    /* Retrieve the performance frequency and initialize the timer ticks */
    NtQueryPerformanceCounter(&CountStart, &FreqCount);
    if (FreqCount.QuadPart == 0)
    {
        wprintf(L"FATAL: Performance counter not available\n");
    }
 
    /* Open the BEEP device */
    RtlInitUnicodeString(&BeepDevice, L"\\Device\\Beep");
    InitializeObjectAttributes(&ObjectAttributes, &BeepDevice, 0, NULL, NULL);
    Status = NtCreateFile(&hBeep,
                          FILE_READ_DATA | FILE_WRITE_DATA,
                          &ObjectAttributes,
                          &IoStatusBlock,
                          NULL,
                          0,
                          FILE_SHARE_READ | FILE_SHARE_WRITE,
                          FILE_OPEN_IF,
                          0,
                          NULL,
                          0);
    if (!NT_SUCCESS(Status))
    {
        DPRINT1("Failed to open the Beep driver, Status 0x%08lx\n", Status);
        // hBeep = INVALID_HANDLE_VALUE;
    }
}