B-Netz: Work on pilot signal generation

The pilot signal to switch to channel 19 can be:
 * a tone
 * a tone that is turned off (notone)
 * positive amplitude
 * negative amplitude

src/amps/amps.c

@@ -400,7 +400,7 @@ int amps_create(int channel, enum amps_chan_type chan_type, const char *sounddev
 	PDEBUG(DAMPS, DEBUG_DEBUG, "Creating 'AMPS' instance for channel = %d (sample rate %d).\n", channel, samplerate);
 
 	/* init general part of transceiver */
-	rc = sender_create(&amps->sender, channel, sounddev, samplerate, cross_channels, rx_gain, 0, 0, write_wave, read_wave, loopback, 0, -1);
+	rc = sender_create(&amps->sender, channel, sounddev, samplerate, cross_channels, rx_gain, 0, 0, write_wave, read_wave, loopback, 0, PILOT_SIGNAL_NONE);
 	if (rc < 0) {
 		PDEBUG(DAMPS, DEBUG_ERROR, "Failed to init transceiver process!\n");
 		goto error;

src/anetz/anetz.c

@@ -156,7 +156,7 @@ int anetz_create(int kanal, const char *sounddev, int samplerate, int cross_chan
 	PDEBUG(DANETZ, DEBUG_DEBUG, "Creating 'A-Netz' instance for 'Kanal' = %d (sample rate %d).\n", kanal, samplerate);
 
 	/* init general part of transceiver */
-	rc = sender_create(&anetz->sender, kanal, sounddev, samplerate, cross_channels, rx_gain, pre_emphasis, de_emphasis, write_wave, read_wave, loopback, loss_volume, -1);
+	rc = sender_create(&anetz->sender, kanal, sounddev, samplerate, cross_channels, rx_gain, pre_emphasis, de_emphasis, write_wave, read_wave, loopback, loss_volume, PILOT_SIGNAL_NONE);
 	if (rc < 0) {
 		PDEBUG(DANETZ, DEBUG_ERROR, "Failed to init 'Sender' processing!\n");
 		goto error;

src/bnetz/bnetz.c

@@ -207,17 +207,15 @@ static struct impulstelegramme *bnetz_telegramm(int digit)
 /* switch pilot signal (tone or file) */
 static void switch_channel_19(bnetz_t *bnetz, int on)
 {
-	if (bnetz->sender.use_pilot_signal >= 0) {
+	/* affects only if pilot signal is used */
-		bnetz->sender.pilot_on = on;
+	sender_pilot(&bnetz->sender, on);
-		return;
-	}
 
-	if (bnetz->pilot_file && bnetz->pilot_is_on != on) {
+	if (bnetz->pilot_file[0] && bnetz->pilot_is_on != on) {
 		FILE *fp;
 
 		fp = fopen(bnetz->pilot_file, "w");
 		if (!fp) {
-			PDEBUG(DBNETZ, DEBUG_ERROR, "Failed to open file '%s' to switch channel 19!\n");
+			PDEBUG(DBNETZ, DEBUG_ERROR, "Failed to open file '%s' to switch channel 19!\n", bnetz->pilot_file);
 			return;
 		}
 		fprintf(fp, "%s\n", (on) ? bnetz->pilot_on : bnetz->pilot_off);
@@ -250,7 +248,7 @@ static void bnetz_go_idle(bnetz_t *bnetz);
 int bnetz_create(int kanal, const char *sounddev, int samplerate, int cross_channels, double rx_gain, int gfs, int pre_emphasis, int de_emphasis, const char *write_wave, const char *read_wave, int loopback, double loss_factor, const char *pilot)
 {
 	bnetz_t *bnetz;
-	int use_pilot_tone = -1;
+	enum pilot_signal pilot_signal = PILOT_SIGNAL_NONE;
 	char pilot_file[256] = "", pilot_on[256] = "", pilot_off[256] = "";
 	int rc;
 
@@ -269,14 +267,17 @@ int bnetz_create(int kanal, const char *sounddev, int samplerate, int cross_chan
 		return -EINVAL;
 	}
 	
+	if (!strcmp(pilot, "notone"))
+		pilot_signal = PILOT_SIGNAL_NOTONE;
+	else
 	if (!strcmp(pilot, "tone"))
-		use_pilot_tone = 2;
+		pilot_signal = PILOT_SIGNAL_TONE;
 	else
 	if (!strcmp(pilot, "positive"))
-		use_pilot_tone = 1;
+		pilot_signal = PILOT_SIGNAL_POSITIVE;
 	else
 	if (!strcmp(pilot, "negative"))
-		use_pilot_tone = 0;
+		pilot_signal = PILOT_SIGNAL_NEGATIVE;
 	else {
 		char *p;
 
@@ -305,7 +306,7 @@ error_pilot:
 	PDEBUG(DBNETZ, DEBUG_DEBUG, "Creating 'B-Netz' instance for 'Kanal' = %d 'Gruppenfreisignal' = %d (sample rate %d).\n", kanal, gfs, samplerate);
 
 	/* init general part of transceiver */
-	rc = sender_create(&bnetz->sender, kanal, sounddev, samplerate, cross_channels, rx_gain, pre_emphasis, de_emphasis, write_wave, read_wave, loopback, loss_factor, use_pilot_tone);
+	rc = sender_create(&bnetz->sender, kanal, sounddev, samplerate, cross_channels, rx_gain, pre_emphasis, de_emphasis, write_wave, read_wave, loopback, loss_factor, pilot_signal);
 	if (rc < 0) {
 		PDEBUG(DBNETZ, DEBUG_ERROR, "Failed to init transceiver process!\n");
 		goto error;

src/bnetz/main.c

@@ -55,11 +55,12 @@ void print_help(const char *arg0)
 	printf("        Set to 19 in order to make the phone transmit at 100 mW instead of\n");
 	printf("        full 15 Watts. If supported, the phone uses the channel with low power\n");
 	printf("        (Kanal kleiner Leistung).\n");
-	printf(" -P --pilot tone | positive | negative | <file>=<on>:<off>\n");
+	printf(" -P --pilot tone | notone | positive | negative | <file>=<on>:<off>\n");
 	printf("        Send a tone, give a signal or write to a file when switching to\n");
 	printf("        channel 19. (paging the phone).\n");
 	printf("        'tone', 'positive', 'negative' is sent on second audio channel.\n");
-	printf("        'tone' sends a tone whenever channel 19 is switchted.\n");
+	printf("        'tone' sends a tone whenever channel 19 is switched.\n");
+	printf("        'notone' sends a tone whenever channel 19 is NOT switched.\n");
 	printf("        'positive' sends a positive signal for channel 19, else negative.\n");
 	printf("        'negative' sends a negative signal for channel 19, else positive.\n");
 	printf("        Example: /sys/class/gpio/gpio17/value=1:0 writes a '1' to\n");

src/cnetz/cnetz.c

@@ -235,7 +235,7 @@ int cnetz_create(int kanal, enum cnetz_chan_type chan_type, const char *sounddev
 
 	/* init general part of transceiver */
 	/* do not enable emphasis, since it is done by cnetz code, not by common sender code */
-	rc = sender_create(&cnetz->sender, kanal, sounddev, samplerate, cross_channels, rx_gain, 0, 0, write_wave, read_wave, loopback, 0, -1);
+	rc = sender_create(&cnetz->sender, kanal, sounddev, samplerate, cross_channels, rx_gain, 0, 0, write_wave, read_wave, loopback, 0, PILOT_SIGNAL_NONE);
 	if (rc < 0) {
 		PDEBUG(DCNETZ, DEBUG_ERROR, "Failed to init transceiver process!\n");
 		goto error;

src/common/sender.c

@@ -35,7 +35,7 @@ static sender_t **sender_tailp = &sender_head;
 int cant_recover = 0;
 
 /* Init transceiver instance and link to list of transceivers. */
-int sender_create(sender_t *sender, int kanal, const char *sounddev, int samplerate, int cross_channels, double rx_gain, int pre_emphasis, int de_emphasis, const char *write_wave, const char *read_wave, int loopback, double loss_volume, int use_pilot_signal)
+int sender_create(sender_t *sender, int kanal, const char *sounddev, int samplerate, int cross_channels, double rx_gain, int pre_emphasis, int de_emphasis, const char *write_wave, const char *read_wave, int loopback, double loss_volume, enum pilot_signal pilot_signal)
 {
 	sender_t *master;
 	int rc = 0;
@@ -49,7 +49,7 @@ int sender_create(sender_t *sender, int kanal, const char *sounddev, int sampler
 	sender->de_emphasis = de_emphasis;
 	sender->loopback = loopback;
 	sender->loss_volume = loss_volume;
-	sender->use_pilot_signal = use_pilot_signal;
+	sender->pilot_signal = pilot_signal;
 	sender->pilotton_phaseshift = 1.0 / ((double)samplerate / 1000.0);
 
 	PDEBUG_CHAN(DSENDER, DEBUG_DEBUG, "Creating 'Sender' instance\n");
@@ -79,12 +79,12 @@ int sender_create(sender_t *sender, int kanal, const char *sounddev, int sampler
 			rc = -EBUSY;
 			goto error;
 		}
-		if (master->use_pilot_signal >= 0) {
+		if (master->pilot_signal != PILOT_SIGNAL_NONE) {
 			PDEBUG(DSENDER, DEBUG_ERROR, "Cannot share sound device with channel %d, because second channel is used for pilot signal!\n", master->kanal);
 			rc = -EBUSY;
 			goto error;
 		}
-		if (use_pilot_signal >= 0) {
+		if (pilot_signal != PILOT_SIGNAL_NONE) {
 			PDEBUG(DSENDER, DEBUG_ERROR, "Cannot share sound device with channel %d, because we need a stereo channel for pilot signal!\n", master->kanal);
 			rc = -EBUSY;
 			goto error;
@@ -277,8 +277,8 @@ cant_recover:
 			if (slave->pre_emphasis)
 				pre_emphasis(&slave->estate, slave_samples, count);
 		}
-		switch (sender->use_pilot_signal) {
+		switch (sender->pilot_signal) {
-		case 2:
+		case PILOT_SIGNAL_TONE:
 			/* tone if pilot signal is on */
 			if (sender->pilot_on)
 				gen_pilotton(sender, pilot, count);
@@ -289,7 +289,18 @@ cant_recover:
 			else
 				rc = sound_write(sender->sound, pilot, samples, count);
 			break;
-		case 1:
+		case PILOT_SIGNAL_NOTONE:
+			/* tone if pilot signal is off */
+			if (!sender->pilot_on)
+				gen_pilotton(sender, pilot, count);
+			else
+				memset(pilot, 0, count << 1);
+			if (!sender->cross_channels)
+				rc = sound_write(sender->sound, samples, pilot, count);
+			else
+				rc = sound_write(sender->sound, pilot, samples, count);
+			break;
+		case PILOT_SIGNAL_POSITIVE:
 			/* positive signal if pilot signal is on */
 			if (sender->pilot_on)
 				memset(pilot, 127, count << 1);
@@ -300,7 +311,7 @@ cant_recover:
 			else
 				rc = sound_write(sender->sound, pilot, samples, count);
 			break;
-		case 0:
+		case PILOT_SIGNAL_NEGATIVE:
 			/* negative signal if pilot signal is on */
 			if (sender->pilot_on)
 				memset(pilot, 128, count << 1);
@@ -393,3 +404,8 @@ cant_recover:
 	}
 }
 
+void sender_pilot(sender_t *sender, int on)
+{
+	sender->pilot_on = on;
+}
+

src/common/sender.h

@@ -8,6 +8,15 @@
 
 #define MAX_SENDER	16
 
+/* how to send a 'pilot' signal (trigger transmitter) */
+enum pilot_signal {
+	PILOT_SIGNAL_NONE = 0,
+	PILOT_SIGNAL_TONE,
+	PILOT_SIGNAL_NOTONE,
+	PILOT_SIGNAL_POSITIVE,
+	PILOT_SIGNAL_NEGATIVE,
+};
+
 /* common structure of each transmitter */
 typedef struct sender {
 	struct sender		*next;
@@ -47,7 +56,7 @@ typedef struct sender {
 	loss_t			loss;
 
 	/* pilot tone */
-	int			use_pilot_signal;	/* -1 if not used, 1 for positive, 0 for negative, 2 for tone */
+	enum pilot_signal	pilot_signal;		/* if pilot signal is used and how it is performed */
 	int			pilot_on;		/* 1 or 0 for on or off */
 	double			pilotton_phaseshift;	/* phase to shift every sample */
 	double			pilotton_phase; 	/* current phase */
@@ -60,9 +69,10 @@ typedef struct sender {
 extern sender_t *sender_head;
 extern int cant_recover;
 
-int sender_create(sender_t *sender, int kanal, const char *sounddev, int samplerate, int cross_channels, double rx_gain, int pre_emphasis, int de_emphasis, const char *write_wave, const char *read_wave, int loopback, double loss_volume, int use_pilot_signal);
+int sender_create(sender_t *sender, int kanal, const char *sounddev, int samplerate, int cross_channels, double rx_gain, int pre_emphasis, int de_emphasis, const char *write_wave, const char *read_wave, int loopback, double loss_volume, enum pilot_signal pilot_signal);
 void sender_destroy(sender_t *sender);
 void process_sender_audio(sender_t *sender, int *quit, int latspl);
 void sender_send(sender_t *sender, int16_t *samples, int count);
 void sender_receive(sender_t *sender, int16_t *samples, int count);
+void sender_pilot(sender_t *sender, int on);
 

src/nmt/nmt.c

@@ -334,7 +334,7 @@ int nmt_create(int channel, enum nmt_chan_type chan_type, const char *sounddev,
 	PDEBUG(DNMT, DEBUG_DEBUG, "Creating 'NMT' instance for channel = %d (sample rate %d).\n", channel, samplerate);
 
 	/* init general part of transceiver */
-	rc = sender_create(&nmt->sender, channel, sounddev, samplerate, cross_channels, rx_gain, pre_emphasis, de_emphasis, write_wave, read_wave, loopback, 0, -1);
+	rc = sender_create(&nmt->sender, channel, sounddev, samplerate, cross_channels, rx_gain, pre_emphasis, de_emphasis, write_wave, read_wave, loopback, 0, PILOT_SIGNAL_NONE);
 	if (rc < 0) {
 		PDEBUG(DNMT, DEBUG_ERROR, "Failed to init transceiver process!\n");
 		goto error;