在Win9x/NT下如何用VC控制PC Speaker

[pccrazy]

在Win9x/NT下如何用VC控制PC Speaker,不是用 MessageBeep();

[xubin_sh]

The Beep function generates simple tones on the speaker. The function is synchronous; it does not return control to its caller until the sound finishes.

BOOL Beep(
DWORD dwFreq, // sound frequency, in hertz
DWORD dwDuration // sound duration, in milliseconds
);

[springsea]

我试过了，好使呀，原码：#include <stdio.h>
#include <windows.h>
#include <math.h>
#include <conio.h>

typedef struct {
short int pitch;
short int duration;
} NOTE;

/*
* Table of notes. Given in half steps. It's a communication from
* the "other side."
*/
NOTE notes[] = {{14, 500}, {16, 500}, {12, 500}, {0, 500}, {7, 1000}};

/*********************************************************************
Set PC's speaker frequency in Hz. The speaker is controlled by an
Intel 8253/8254 timer at I/O port addresses 0x40-0x43.
*********************************************************************/
void setfreq(int hz)
{
hz = 1193180 / hz; // clocked at 1.19MHz
_outp(0x43, 0xb6); // timer 2, square wave
_outp(0x42, hz);
_outp(0x42, hz >> 8);
}

/*********************************************************************
Pass a note, in half steps relative to 400 Hz. The 12 step scale
is an exponential thing. The speaker control is at port 0x61.
Setting the lowest two bits enables timer 2 of the 8253/8254 timer
and turns on the speaker.
*********************************************************************/
void playnote(NOTE note)
{
_outp(0x61, _inp(0x61) and 0x03); // start speaker going
setfreq((int)(400 * pow(2, note.pitch / 12.0)));
Sleep(note.duration);
_outp(0x61, _inp(0x61) & ~0x03); // stop that racket!
}

int main()
{

for(i=0; i < sizeof(notes)/sizeof(int); ++i)
playnote(notes[i]);

return 0;
}

[springsea]

对了，nt下有点麻烦，NT不支持直接对端口操作！

[pccrazy]

这种方式我早就试过了，不行的

[younet]

NT下就需要用NT Driver啦，编写一个驱动程序吧

[dowinlee]

NT下，只需要用Beep()就可以了。