updated ui added new features

2026-07-07 09:16:44 +10:00 · 2025-12-27 15:32:32 -07:00
parent 02ca7801ea
commit a2cfae3a22
589 changed files with 181780 additions and 569 deletions
@@ -0,0 +1,151 @@
+/*!
+ * Fixed-point tone generator.
+ *
+ * The code here implements a simple fixed-point tone generator that uses
+ * integer arithmetic to generate a sinusoid at a fixed sample rate of
+ * 16kHz.
+ *
+ * To set the initial state of the state machine, you specify a frequency
+ * and duration using tone_reset.  The corresponding C file embeds a
+ * sinusoid look-up table.  The total number of samples is computed for
+ * the given time and used to initialise 'remain', 'time' is initialised
+ * to 0, and 'step' gives the amount to increment 'time' by each iteration.
+ *
+ * The samples are retrieved by repeatedly calling tone_next.  This
+ * advances 'time' and decrements 'remain'.  The tone is complete when
+ * 'remain' is zero.
+ *
+ * Author Stuart Longland <me@vk4msl.id.au>
+ * Copyright (C) 2015 FreeDV project.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License version 2.1,
+ * as published by the Free Software Foundation.  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 Lesser General Public
+ * License along with this program; if not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+#include "tone.h"
+
+/*! Fixed-point shift factor */
+#define TONE_SHIFT	(12)
+
+/*! Static compiled quarter-sinusoid. */
+static const int16_t partial_sine[] = {
+   830,   2488,   4140,   5781,   7407,   9014,  10598,  12155,
+ 13681,  15171,  16623,  18031,  19394,  20707,  21967,  23170,
+ 24314,  25395,  26411,  27360,  28238,  29043,  29774,  30429,
+ 31006,  31503,  31919,  32253,  32504,  32672,  32756
+};
+
+/*! Length of quarter-sinusoid in samples */
+#define TONE_PART_SINE_LEN	(sizeof(partial_sine)\
+			/sizeof(partial_sine[0]))
+
+/*! Total length of sinusoid */
+#define TONE_SINE_LEN	((TONE_PART_SINE_LEN*4)+4)
+
+/*!
+ * Generate a sine from the quarter-waveform.
+ */
+static int16_t tone_sine(uint8_t sample)
+{
+	/* Key points */
+	if ((sample % (TONE_SINE_LEN/2)) == 0)
+		/* Zero crossings */
+		return 0;
+	if (sample == TONE_SINE_LEN/4)
+		/* Maximum */
+		return INT16_MAX;
+	if (sample == (3*TONE_SINE_LEN)/4)
+		/* Minimum */
+		return INT16_MIN;
+
+	if (sample < TONE_SINE_LEN/4)
+		/* First quarter of sine wave */
+		return partial_sine[sample-1];
+
+	if (sample < (TONE_SINE_LEN/2))
+		/* Second quarter */
+		return partial_sine[(TONE_SINE_LEN/2)-sample-1];
+	if (sample < ((3*TONE_SINE_LEN)/4))
+		/* Third quarter */
+		return -partial_sine[(sample-3) % TONE_PART_SINE_LEN];
+	if (sample < TONE_SINE_LEN)
+		/* Final quarter */
+		return -partial_sine[TONE_SINE_LEN-sample-1];
+	/* We should not get here */
+	return 0;
+}
+
+/*!
+ * Re-set the tone generator.
+ *
+ * @param	tone_gen	Tone generator to reset.
+ * @param	freq		Frequency in Hz, 0 = silence.
+ * @param	duration	Duration in milliseconds.  0 to stop.
+ */
+void tone_reset(
+	struct tone_gen_t* const tone_gen,
+	uint16_t freq, uint16_t duration)
+{
+	if (freq)
+		/* Compute the time step */
+		tone_gen->step = (((2*freq*TONE_SINE_LEN) << TONE_SHIFT)
+				/ ((2*TONE_FS) + 1) + 1);
+	else
+		/* DC tone == silence */
+		tone_gen->step = 0;
+
+	/* Compute remaining samples */
+	tone_gen->remain = (uint16_t)(
+			((uint32_t)(TONE_FS * duration)) / 1000);
+
+	/* Initialise the sample counter */
+	tone_gen->sample = 0;
+}
+
+/*!
+ * Retrieve the next sample from the tone generator.
+ * @param	tone_gen	Tone generator to update.
+ */
+int16_t tone_next(
+	struct tone_gen_t* const tone_gen)
+{
+	if (!tone_gen)
+		return 0;
+	if (!tone_gen->remain)
+		return 0;
+	if (!tone_gen->step) {
+		/* Special case, emit silence */
+		tone_gen->remain--;
+		return 0;
+	}
+
+	/* Compute sample index */
+	uint16_t sample_int = ((tone_gen->sample) >> TONE_SHIFT)
+				% TONE_SINE_LEN;
+
+	/* Advance tone generator state */
+	tone_gen->sample += tone_gen->step;
+	tone_gen->remain--;
+
+	return tone_sine(sample_int);
+}
+
+/*!
+ * Retrieve the current time in milliseconds.
+ */
+uint32_t tone_msec(const struct tone_gen_t* const tone_gen)
+{
+	uint64_t ms = tone_gen->sample;
+	ms *= 1000;
+	ms /= TONE_FS;
+	return ms >> TONE_SHIFT;
+}