DTMF encoder

* Added DTMF encoder accessible as a macro tag
    - <DTMF:string of chars> where string of chars can
      contain 0..9,space,-,comma,*,#,A..D
    - space, hyphen and comma insert a 50 msec silent
      period in the transmissions

src/include/configuration.h

@@ -608,6 +608,7 @@
               "Single tone at center of modem BW, carrier detect for amplifiers",       \
               0.0)                                                                      \
         ELEM_(bool, macroCWid, "", "",  false)                                          \
+        ELEM_(std::string, DTMFstr, "", "", "")                                         \
         ELEM_(int, videowidth, "VIDEOWIDTH",                                            \
               "Video ID text width (characters per row)",                               \
               1)                                                                        \

src/include/modem.h

@@ -65,6 +65,9 @@ protected:
 	bool s2n_valid;
 
 	unsigned cap;
+	static int DTMF_row[];
+	static int DTMF_col[];
+
 public:
 	modem();
 	virtual ~modem(){};
@@ -177,6 +180,11 @@ public:
 	void	cwid_sendtext (const std::string& s);
 	void	cwid();
 
+// for DTMF transmission
+	void DTMF_silence(int);
+	void DTMF_two_tones(int);
+	void DTMF_send();
+
 // for noise tests
 private:
 	void	add_noise(double *, int);

src/misc/macroedit.cxx

@@ -158,6 +158,7 @@ void loadBrowser(Fl_Widget *widget) {
 	w->add(_("<TEXT>\tvideo text"));
 	w->add(_("<TXRSID:on|off|t>\tTx RSID on,off,toggle"));
 	w->add(_("<RXRSID:on|off|t>\tRx RSID on,off,toggle"));
+	w->add(_("<DTMF:digits>\tTx digits string"));
 
 	w->add(LINE_SEP);
 	w->add(_("<POST:+/-nn.n>\tCW QSK post-timing"));

src/misc/macros.cxx

@@ -141,6 +141,7 @@ void pAFC(string &, size_t &);
 void pLOCK(string &, size_t &);
 void pRX_RSID(string &, size_t &);
 void pTX_RSID(string &, size_t &);
+void pDTMF(string &, size_t &);
 
 #ifdef __WIN32__
 void pTALK(string &, size_t &);
@@ -227,6 +228,7 @@ MTAGS mtags[] = {
 {"<LOCK:",		pLOCK},
 {"<RXRSID:",	pRX_RSID},
 {"<TXRSID:",	pTX_RSID},
+{"<DTMF:",		pDTMF},
 {"<SRCHUP>",	pSRCHUP},
 {"<SRCHDN>",	pSRCHDN},
 {"<GOHOME>",	pGOHOME},
@@ -627,6 +629,13 @@ void pCWID(string &s, size_t &i)
 	s.replace( i, 6, "");
 }
 
+void pDTMF(string &s, size_t &i)
+{
+	size_t endbracket = s.find('>',i);
+	progdefaults.DTMFstr = s.substr(i + 6, endbracket - i - 6);
+	s.replace(i, endbracket - i + 1, "");
+}
+
 void pRX(string &s, size_t &i)
 {
 	s.replace (i, 4, "^r");

src/trx/modem.cxx

@@ -971,3 +971,89 @@ mfntchr idch2[] = {
 };
 
 
+//======================================================================
+// DTMF tone transmit
+//======================================================================
+int modem::DTMF_row[] = {
+941, 697, 697, 697, 770, 770, 770, 852, 852, 852, 941, 941, 697, 770, 852, 941};
+//0,   1,   2,   3,   4,   5,   6,   7,   8,   9,   *,   #,   A,   B,   C,   D
+
+int modem::DTMF_col[] = { 
+1336, 1209, 1336, 1477, 1209, 1336, 1477, 1209, 1336, 1477, 1209, 1477, 1633, 1633, 1633, 1633};
+// 0,    1,    2,    3,    4,    5,    6,    7,    8,    9,    *,    #,    A,    B,    C,    D
+
+//----------------------------------------------------------------------
+// transmit silence for specified time duration
+//----------------------------------------------------------------------
+
+void modem::DTMF_silence(int duration)
+{
+	double sr = active_modem->get_samplerate();
+	int length = duration * sr / 1000;
+	memset(outbuf, 0, length * sizeof(*outbuf));
+	active_modem->ModulateXmtr(outbuf, length);
+}
+
+//----------------------------------------------------------------------
+// transmit DTMF tones for specific time interval
+//----------------------------------------------------------------------
+
+void modem::DTMF_two_tones(int rc)
+{
+	if (rc < 0 || rc > 15) return;
+	double sr = active_modem->get_samplerate();
+	double phaseincr = 2.0 * M_PI * DTMF_row[rc] / sr;
+	double phase = 0;
+printf("%d %d\n", DTMF_row[rc], DTMF_col[rc]);
+	int length = 50 * sr / 1000;
+
+	for (int i = 0; i < length; i++) {
+		outbuf[i] = 0.5 * sin(phase);
+		phase += phaseincr;
+	}
+
+	phaseincr = 2.0 * M_PI * DTMF_col[rc] / sr;
+	phase = 0;
+	for (int i = 0; i < length; i++) {
+		outbuf[i] += 0.5 * sin(phase);
+		phase += phaseincr;
+	}
+	for (int i = 0; i < RT; i++) {
+		outbuf[i] *= cwid_keyshape[i];
+		outbuf[length - 1 - i] *= cwid_keyshape[i];
+	}
+
+	active_modem->ModulateXmtr(outbuf, length);
+
+}
+
+//----------------------------------------------------------------------
+// transmit the string contained in progdefaults.DTMFstr and output as 
+// dtmf valid characters, 0-9, *, #, A-D
+// each pair of tones is separated by 50ms silence
+// 500 msec silence for ' ', ',' or '-'
+// 50 msec silence for invalid characters
+//----------------------------------------------------------------------
+
+void modem::DTMF_send()
+{
+	if (progdefaults.DTMFstr.empty()) return;
+
+	int c = 0;
+
+	RT = (int) (samplerate * 4 / 1000.0); // 4 msec rise/fall time
+	cwid_makeshape();
+
+	for(size_t i = 0; i < progdefaults.DTMFstr.length(); i++) {
+		c = progdefaults.DTMFstr[i];
+		if (c == ' ' || c == ',' || c == '-') DTMF_silence(50);
+		else if (c >= '0' && c <= '9')        DTMF_two_tones(c - '0');
+		else if (c == '*')                    DTMF_two_tones(10);
+		else if (c == '#')                    DTMF_two_tones(11);
+		else if (c >= 'A' && c <= 'D')        DTMF_two_tones(12 + c - 'A');
+		else if (c >= 'a' && c <= 'd')        DTMF_two_tones(12 + c - 'a');
+		DTMF_silence(50);
+	}
+	progdefaults.DTMFstr.clear();
+}
+

src/trx/trx.cxx

@@ -312,6 +312,8 @@ void trx_trx_transmit_loop()
 		if (progdefaults.TransmitRSid)
 			ReedSolomon->send(true);
 
+		active_modem->DTMF_send();
+
 		while (trx_state == STATE_TX) {
 			try {
 				if (active_modem->tx_process() < 0)