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/*
* Some sound testing.
*
* Copyright (C) 2014 Tomasz Kramkowski <tk@the-tk.com>
*
* This program is free software. It is licensed under version 3 of the
* GNU General Public License.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see [http://www.gnu.org/licenses/].
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <math.h>
static long int sfreq;
void playtone(long int, int, long int, float);
void playtone_pwm(long int, long int, int, long int);
void sinetone(float, int, float);
int main(int argc, char **argv)
{
if (argc != 2) {
fprintf(stderr, "Usage: %s <frequency>\n", argv[0]);
exit(1);
}
sfreq = strtol(argv[1], NULL, 10);
/*for (int i = 1; i < 3000; i++)*/
/*sinetone(i, 127, 5);*/
for (int i = 1; i < 3000; i++)
sinetone(i, 127, 1.0/i * 1000.0);
/*for (int i = 0; i < 1000; i++) {*/
/*long int pulse_width = 441;*/
/*float duty_cycle = (sinf(i / 5.0 * M_PI) + 1.0) / 2.0;*/
/*for (int ii = 0; ii < ceilf(duty_cycle * pulse_width); ii++)*/
/*putchar(0);*/
/*for (int ii = 0; ii < floorf((1.0 - duty_cycle) * pulse_width); ii++)*/
/*putchar(255);*/
/*}*/
/*playtone_pwm(160, 80, 127, 10000);*/
/*for (float i = 0; i < 1; i+=0.01)*/
/*playtone(100, 127, 10, i);*/
return 0;
}
void playtone(long int freq, int ampl, long int time, float duty_cycle)
{
if (ampl > 127)
ampl = 127;
long int pulse_width = sfreq / freq;
long int total_waves = time * freq / 1000;
for (long int wi = 0; wi < total_waves; wi++) {
int i;
for (i = 0; i < (int)((float)pulse_width * duty_cycle); i++)
putchar(128-ampl);
for (i = 0; i < (int)((float)pulse_width * (1.0 - duty_cycle)); i++)
putchar(255+ampl);
}
}
void playtone_pwm(long int freq, long int freq_pwm, int ampl, long int time)
{
if (ampl > 127)
ampl = 127;
long int pulse_width = sfreq / freq;
long int total_waves = time * freq / 1000;
for (long int wi = 0; wi < total_waves; wi++) {
int i;
float pulse_proportion = (sinf((float)wi / (float)total_waves * time / freq_pwm * 2 * M_PI) + 1) / 2;
for (i = 0; i < (int)((float)pulse_width * pulse_proportion); i++)
putchar(128-ampl);
for (i = 0; i < (int)((float)pulse_width * (1.0 - pulse_proportion)); i++)
putchar(255+ampl);
}
}
void sinetone(float freq, int ampl, float time)
{
if (ampl > 127) ampl = 127;
float wave_length = sfreq / freq;
for (long int wi = 0; wi < time * sfreq / 1000; wi++)
putchar((char)((sinf((float)wi / wave_length * M_PI_2 * 4) + 1) * ampl));
}
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