www.pudn.com > soundmodem.rar > sm_fsk9600.c
/*****************************************************************************/
/*
* sm_fsk9600.c -- soundcard radio modem driver,
* 9600 baud G3RUH compatible FSK modem
*
* Copyright (C) 1996 Thomas Sailer (sailer@ife.ee.ethz.ch)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Please note that the GPL allows you to use the driver, NOT the radio.
* In order to use the radio, you need a license from the communications
* authority of your country.
*
*/
#include "sm.h"
#include "sm_tbl_fsk9600.h"
/* --------------------------------------------------------------------- */
struct demod_state_fsk96 {
unsigned int shreg;
unsigned long descram;
unsigned int bit_pll;
unsigned char last_sample;
unsigned int dcd_shreg;
int dcd_sum0, dcd_sum1, dcd_sum2;
unsigned int dcd_time;
};
struct mod_state_fsk96 {
unsigned int shreg;
unsigned long scram;
unsigned char tx_bit;
unsigned char *txtbl;
unsigned int txphase;
};
/* --------------------------------------------------------------------- */
#define DESCRAM_TAP1 0x20000
#define DESCRAM_TAP2 0x01000
#define DESCRAM_TAP3 0x00001
#define DESCRAM_TAPSH1 17
#define DESCRAM_TAPSH2 12
#define DESCRAM_TAPSH3 0
#define SCRAM_TAP1 0x20000 /* X^17 */
#define SCRAM_TAPN 0x00021 /* X^0+X^5 */
/* --------------------------------------------------------------------- */
static void modulator_9600_4_u8(struct sm_state *sm, unsigned char *buf, unsigned int buflen)
{
struct mod_state_fsk96 *st = (struct mod_state_fsk96 *)(&sm->m);
for (; buflen > 0; buflen--) {
if (!st->txphase++) {
if (st->shreg <= 1)
st->shreg = hdlcdrv_getbits(&sm->hdrv) | 0x10000;
st->scram = (st->scram << 1) | (st->scram & 1);
st->scram ^= !(st->shreg & 1);
st->shreg >>= 1;
if (st->scram & (SCRAM_TAP1 << 1))
st->scram ^= SCRAM_TAPN << 1;
st->tx_bit = (st->tx_bit << 1) | (!!(st->scram & (SCRAM_TAP1 << 2)));
st->txtbl = fsk96_txfilt_4 + (st->tx_bit & 0xff);
}
if (st->txphase >= 4)
st->txphase = 0;
*buf++ = *st->txtbl;
st->txtbl += 0x100;
}
}
/* --------------------------------------------------------------------- */
static void modulator_9600_4_s16(struct sm_state *sm, short *buf, unsigned int buflen)
{
struct mod_state_fsk96 *st = (struct mod_state_fsk96 *)(&sm->m);
for (; buflen > 0; buflen--) {
if (!st->txphase++) {
if (st->shreg <= 1)
st->shreg = hdlcdrv_getbits(&sm->hdrv) | 0x10000;
st->scram = (st->scram << 1) | (st->scram & 1);
st->scram ^= !(st->shreg & 1);
st->shreg >>= 1;
if (st->scram & (SCRAM_TAP1 << 1))
st->scram ^= SCRAM_TAPN << 1;
st->tx_bit = (st->tx_bit << 1) | (!!(st->scram & (SCRAM_TAP1 << 2)));
st->txtbl = fsk96_txfilt_4 + (st->tx_bit & 0xff);
}
if (st->txphase >= 4)
st->txphase = 0;
*buf++ = ((*st->txtbl)-0x80) << 8;
st->txtbl += 0x100;
}
}
/* --------------------------------------------------------------------- */
static void demodulator_9600_4_u8(struct sm_state *sm, const unsigned char *buf, unsigned int buflen)
{
struct demod_state_fsk96 *st = (struct demod_state_fsk96 *)(&sm->d);
static const int pll_corr[2] = { -0x1000, 0x1000 };
unsigned char curbit;
unsigned int descx;
for (; buflen > 0; buflen--, buf++) {
st->dcd_shreg <<= 1;
st->bit_pll += 0x4000;
curbit = (*buf >= 0x80);
if (st->last_sample ^ curbit) {
st->dcd_shreg |= 1;
st->bit_pll += pll_corr[st->bit_pll < 0xa000];
st->dcd_sum0 += 8 * hweight8(st->dcd_shreg & 0x0c) -
!!(st->dcd_shreg & 0x10);
}
st->last_sample = curbit;
hdlcdrv_channelbit(&sm->hdrv, st->last_sample);
if ((--st->dcd_time) <= 0) {
hdlcdrv_setdcd(&sm->hdrv, (st->dcd_sum0 +
st->dcd_sum1 +
st->dcd_sum2) < 0);
st->dcd_sum2 = st->dcd_sum1;
st->dcd_sum1 = st->dcd_sum0;
st->dcd_sum0 = 2; /* slight bias */
st->dcd_time = 240;
}
if (st->bit_pll >= 0x10000) {
st->bit_pll &= 0xffff;
st->descram = (st->descram << 1) | curbit;
descx = st->descram ^ (st->descram >> 1);
descx ^= ((descx >> DESCRAM_TAPSH1) ^
(descx >> DESCRAM_TAPSH2));
st->shreg >>= 1;
st->shreg |= (!(descx & 1)) << 16;
if (st->shreg & 1) {
hdlcdrv_putbits(&sm->hdrv, st->shreg >> 1);
st->shreg = 0x10000;
}
diag_trigger(sm);
}
diag_add_one(sm, ((short)(*buf - 0x80)) << 8);
}
}
/* --------------------------------------------------------------------- */
static void demodulator_9600_4_s16(struct sm_state *sm, const short *buf, unsigned int buflen)
{
struct demod_state_fsk96 *st = (struct demod_state_fsk96 *)(&sm->d);
static const int pll_corr[2] = { -0x1000, 0x1000 };
unsigned char curbit;
unsigned int descx;
for (; buflen > 0; buflen--, buf++) {
st->dcd_shreg <<= 1;
st->bit_pll += 0x4000;
curbit = (*buf >= 0);
if (st->last_sample ^ curbit) {
st->dcd_shreg |= 1;
st->bit_pll += pll_corr[st->bit_pll < 0xa000];
st->dcd_sum0 += 8 * hweight8(st->dcd_shreg & 0x0c) -
!!(st->dcd_shreg & 0x10);
}
st->last_sample = curbit;
hdlcdrv_channelbit(&sm->hdrv, st->last_sample);
if ((--st->dcd_time) <= 0) {
hdlcdrv_setdcd(&sm->hdrv, (st->dcd_sum0 +
st->dcd_sum1 +
st->dcd_sum2) < 0);
st->dcd_sum2 = st->dcd_sum1;
st->dcd_sum1 = st->dcd_sum0;
st->dcd_sum0 = 2; /* slight bias */
st->dcd_time = 240;
}
if (st->bit_pll >= 0x10000) {
st->bit_pll &= 0xffff;
st->descram = (st->descram << 1) | curbit;
descx = st->descram ^ (st->descram >> 1);
descx ^= ((descx >> DESCRAM_TAPSH1) ^
(descx >> DESCRAM_TAPSH2));
st->shreg >>= 1;
st->shreg |= (!(descx & 1)) << 16;
if (st->shreg & 1) {
hdlcdrv_putbits(&sm->hdrv, st->shreg >> 1);
st->shreg = 0x10000;
}
diag_trigger(sm);
}
diag_add_one(sm, *buf);
}
}
/* --------------------------------------------------------------------- */
static void modulator_9600_5_u8(struct sm_state *sm, unsigned char *buf, unsigned int buflen)
{
struct mod_state_fsk96 *st = (struct mod_state_fsk96 *)(&sm->m);
for (; buflen > 0; buflen--) {
if (!st->txphase++) {
if (st->shreg <= 1)
st->shreg = hdlcdrv_getbits(&sm->hdrv) | 0x10000;
st->scram = (st->scram << 1) | (st->scram & 1);
st->scram ^= !(st->shreg & 1);
st->shreg >>= 1;
if (st->scram & (SCRAM_TAP1 << 1))
st->scram ^= SCRAM_TAPN << 1;
st->tx_bit = (st->tx_bit << 1) | (!!(st->scram & (SCRAM_TAP1 << 2)));
st->txtbl = fsk96_txfilt_5 + (st->tx_bit & 0xff);
}
if (st->txphase >= 5)
st->txphase = 0;
*buf++ = *st->txtbl;
st->txtbl += 0x100;
}
}
/* --------------------------------------------------------------------- */
static void modulator_9600_5_s16(struct sm_state *sm, short *buf, unsigned int buflen)
{
struct mod_state_fsk96 *st = (struct mod_state_fsk96 *)(&sm->m);
for (; buflen > 0; buflen--) {
if (!st->txphase++) {
if (st->shreg <= 1)
st->shreg = hdlcdrv_getbits(&sm->hdrv) | 0x10000;
st->scram = (st->scram << 1) | (st->scram & 1);
st->scram ^= !(st->shreg & 1);
st->shreg >>= 1;
if (st->scram & (SCRAM_TAP1 << 1))
st->scram ^= SCRAM_TAPN << 1;
st->tx_bit = (st->tx_bit << 1) | (!!(st->scram & (SCRAM_TAP1 << 2)));
st->txtbl = fsk96_txfilt_5 + (st->tx_bit & 0xff);
}
if (st->txphase >= 5)
st->txphase = 0;
*buf++ = ((*st->txtbl)-0x80)<<8;
st->txtbl += 0x100;
}
}
/* --------------------------------------------------------------------- */
static void demodulator_9600_5_u8(struct sm_state *sm, const unsigned char *buf, unsigned int buflen)
{
struct demod_state_fsk96 *st = (struct demod_state_fsk96 *)(&sm->d);
static const int pll_corr[2] = { -0x1000, 0x1000 };
unsigned char curbit;
unsigned int descx;
for (; buflen > 0; buflen--, buf++) {
st->dcd_shreg <<= 1;
st->bit_pll += 0x3333;
curbit = (*buf >= 0x80);
if (st->last_sample ^ curbit) {
st->dcd_shreg |= 1;
st->bit_pll += pll_corr[st->bit_pll < 0x9999];
st->dcd_sum0 += 16 * hweight8(st->dcd_shreg & 0x0c) -
hweight8(st->dcd_shreg & 0x70);
}
st->last_sample = curbit;
hdlcdrv_channelbit(&sm->hdrv, st->last_sample);
if ((--st->dcd_time) <= 0) {
hdlcdrv_setdcd(&sm->hdrv, (st->dcd_sum0 +
st->dcd_sum1 +
st->dcd_sum2) < 0);
st->dcd_sum2 = st->dcd_sum1;
st->dcd_sum1 = st->dcd_sum0;
st->dcd_sum0 = 2; /* slight bias */
st->dcd_time = 240;
}
if (st->bit_pll >= 0x10000) {
st->bit_pll &= 0xffff;
st->descram = (st->descram << 1) | curbit;
descx = st->descram ^ (st->descram >> 1);
descx ^= ((descx >> DESCRAM_TAPSH1) ^
(descx >> DESCRAM_TAPSH2));
st->shreg >>= 1;
st->shreg |= (!(descx & 1)) << 16;
if (st->shreg & 1) {
hdlcdrv_putbits(&sm->hdrv, st->shreg >> 1);
st->shreg = 0x10000;
}
diag_trigger(sm);
}
diag_add_one(sm, ((short)(*buf - 0x80)) << 8);
}
}
/* --------------------------------------------------------------------- */
static void demodulator_9600_5_s16(struct sm_state *sm, const short *buf, unsigned int buflen)
{
struct demod_state_fsk96 *st = (struct demod_state_fsk96 *)(&sm->d);
static const int pll_corr[2] = { -0x1000, 0x1000 };
unsigned char curbit;
unsigned int descx;
for (; buflen > 0; buflen--, buf++) {
st->dcd_shreg <<= 1;
st->bit_pll += 0x3333;
curbit = (*buf >= 0);
if (st->last_sample ^ curbit) {
st->dcd_shreg |= 1;
st->bit_pll += pll_corr[st->bit_pll < 0x9999];
st->dcd_sum0 += 16 * hweight8(st->dcd_shreg & 0x0c) -
hweight8(st->dcd_shreg & 0x70);
}
st->last_sample = curbit;
hdlcdrv_channelbit(&sm->hdrv, st->last_sample);
if ((--st->dcd_time) <= 0) {
hdlcdrv_setdcd(&sm->hdrv, (st->dcd_sum0 +
st->dcd_sum1 +
st->dcd_sum2) < 0);
st->dcd_sum2 = st->dcd_sum1;
st->dcd_sum1 = st->dcd_sum0;
st->dcd_sum0 = 2; /* slight bias */
st->dcd_time = 240;
}
if (st->bit_pll >= 0x10000) {
st->bit_pll &= 0xffff;
st->descram = (st->descram << 1) | curbit;
descx = st->descram ^ (st->descram >> 1);
descx ^= ((descx >> DESCRAM_TAPSH1) ^
(descx >> DESCRAM_TAPSH2));
st->shreg >>= 1;
st->shreg |= (!(descx & 1)) << 16;
if (st->shreg & 1) {
hdlcdrv_putbits(&sm->hdrv, st->shreg >> 1);
st->shreg = 0x10000;
}
diag_trigger(sm);
}
diag_add_one(sm, *buf);
}
}
/* --------------------------------------------------------------------- */
static void demod_init_9600(struct sm_state *sm)
{
struct demod_state_fsk96 *st = (struct demod_state_fsk96 *)(&sm->d);
st->dcd_time = 240;
st->dcd_sum0 = 2;
}
/* --------------------------------------------------------------------- */
const struct modem_tx_info sm_fsk9600_4_tx = {
"fsk9600", sizeof(struct mod_state_fsk96), 38400, 9600,
modulator_9600_4_u8, modulator_9600_4_s16, NULL
};
const struct modem_rx_info sm_fsk9600_4_rx = {
"fsk9600", sizeof(struct demod_state_fsk96), 38400, 9600, 1, 4,
demodulator_9600_4_u8, demodulator_9600_4_s16, demod_init_9600
};
/* --------------------------------------------------------------------- */
const struct modem_tx_info sm_fsk9600_5_tx = {
"fsk9600", sizeof(struct mod_state_fsk96), 48000, 9600,
modulator_9600_5_u8, modulator_9600_5_s16, NULL
};
const struct modem_rx_info sm_fsk9600_5_rx = {
"fsk9600", sizeof(struct demod_state_fsk96), 48000, 9600, 1, 5,
demodulator_9600_5_u8, demodulator_9600_5_s16, demod_init_9600
};
/* --------------------------------------------------------------------- */