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/*
** MKTONE.C
**
** Original Copyright 1988-1991 by Bob Stout as part of
** the MicroFirm Function Library (MFL)
**
** This subset version is functionally identical to the
** version originally published by the author in Tech Specialist
** magazine and is hereby donated to the public domain.
*/
#include "uclock.h"
#include "sound.h"
static int usec_timeout(uclock_t start, uclock_t finish, uclock_t usecs)
{
if (usecs >= (finish - start))
return 0;
else return 1;
}
void dosound(int freq)
{
unsigned i;
outp(C8253, SETIMER);
i = (unsigned)freq%256;
outp(F8253, i);
i = (unsigned)freq/256;
outp(F8253, i);
}
void mktone(int freq, int update, unsigned delay)
{
uclock_t start;
if (0 == freq)
{
soundoff();
return;
}
dosound(freq);
if (update != UPDATE)
soundon();
if (delay == 0)
return;
start = usec_clock();
while (!usec_timeout(start, usec_clock(), 1000L * (long)delay))
;
if (update == TOGGLE)
soundoff();
}
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