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/*
* generic V23 modulator & demodulator
*
* Copyright (c) 1999 Fabrice Bellard.
*
* This code is released under the GNU General Public License version
* 2. Please read the file COPYING to know the exact terms of the
* license.
*/
#include <stdlib.h>
#include <stdio.h>
#include "lm.h"
#include "fsk.h"
#define SAMPLE_RATE 8000
void V23_mod_init(FSK_mod_state *s, int calling, get_bit_func get_bit, void *opaque)
{
if (calling) {
/* 75 bauds */
s->f_lo = 390;
s->f_hi = 450;
s->baud_rate = 75;
} else {
/* 1200 bauds */
s->f_lo = 1300;
s->f_hi = 2100;
s->baud_rate = 1200;
}
s->sample_rate = SAMPLE_RATE;
s->get_bit = get_bit;
s->opaque = opaque;
FSK_mod_init(s);
}
void V23_demod_init(FSK_demod_state *s, int calling, put_bit_func put_bit, void *opaque)
{
if (!calling) {
/* 75 bauds */
s->f_lo = 390;
s->f_hi = 450;
s->baud_rate = 75;
} else {
/* 1200 bauds */
s->f_lo = 1300;
s->f_hi = 2100;
s->baud_rate = 1200;
}
s->sample_rate = SAMPLE_RATE;
s->put_bit = put_bit;
s->opaque = opaque;
FSK_demod_init(s);
}
void V23_init(V23State *s, int calling,
get_bit_func get_bit, put_bit_func put_bit, void *opaque)
{
V23_mod_init(&s->tx, calling, get_bit, opaque);
V23_demod_init(&s->rx, calling, put_bit, opaque);
}
int V23_process(V23State *s, s16 *output, s16 *input, int nb_samples)
{
FSK_mod(&s->tx, output, nb_samples);
FSK_demod(&s->rx, input, nb_samples);
return 0;
}
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