patch-2.1.27 linux/drivers/net/soundmodem/sm_fsk9600.c

• Lines: 240
• Date: Fri Feb 21 14:58:35 1997
• Orig file: v2.1.26/linux/drivers/net/soundmodem/sm_fsk9600.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.26/linux/drivers/net/soundmodem/sm_fsk9600.c linux/drivers/net/soundmodem/sm_fsk9600.c
@@ -0,0 +1,239 @@
+/*****************************************************************************/
+
+/*
+ *	sm_fsk9600.h  --  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;
+};
+
+/* --------------------------------------------------------------------- */
+
+#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(struct sm_state *sm, unsigned char *buf, int buflen)
+{
+	struct mod_state_fsk96 *st = (struct mod_state_fsk96 *)(&sm->m);
+	int j;
+	const unsigned char *cp;
+
+	for (; buflen >= 4; buflen -= 4) {
+		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)));
+		cp = fsk96_txfilt_4 + (st->tx_bit & 0xff);
+		for (j = 0; j < 4; j++, cp += 0x100)
+			*buf++ = *cp;
+	}
+}
+
+/* --------------------------------------------------------------------- */
+
+static void demodulator_9600_4(struct sm_state *sm, unsigned char *buf, 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 modulator_9600_5(struct sm_state *sm, unsigned char *buf, int buflen)
+{
+	struct mod_state_fsk96 *st = (struct mod_state_fsk96 *)(&sm->m);
+	int j;
+	const unsigned char *cp;
+
+	for (; buflen >= 5; buflen -= 5) {
+		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)));
+		cp = fsk96_txfilt_5 + (st->tx_bit & 0xff);
+		for (j = 0; j < 5; j++, cp += 0x100)
+			*buf++ = *cp;
+	}
+}
+
+/* --------------------------------------------------------------------- */
+
+static void demodulator_9600_5(struct sm_state *sm, unsigned char *buf, 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 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, 4,
+	modulator_9600_4, NULL
+};
+
+const struct modem_rx_info sm_fsk9600_4_rx = {
+	"fsk9600", sizeof(struct demod_state_fsk96), 38400, 9600, 4, 4,
+	demodulator_9600_4, demod_init_9600
+};
+
+/* --------------------------------------------------------------------- */
+
+const struct modem_tx_info sm_fsk9600_5_tx = {
+	"fsk9600", sizeof(struct mod_state_fsk96), 48000, 9600, 5, 
+	modulator_9600_5, NULL
+};
+
+const struct modem_rx_info sm_fsk9600_5_rx = {
+	"fsk9600", sizeof(struct demod_state_fsk96), 48000, 9600, 5, 5, 
+	demodulator_9600_5, demod_init_9600
+};
+
+/* --------------------------------------------------------------------- */