From 8702b04e7b99ad872ce2adac2c62cdd448d0ff64 Mon Sep 17 00:00:00 2001
From: boblark <bob@janbob.com>
Date: Thu, 10 Mar 2022 12:19:15 -0800
Subject: [PATCH] Tone detector set to 1209 Hz

---
 examples/ToneDetect1/ToneDetect1.ino | 62 ++++++++++++++++++++++++++++
 1 file changed, 62 insertions(+)
 create mode 100644 examples/ToneDetect1/ToneDetect1.ino

diff --git a/examples/ToneDetect1/ToneDetect1.ino b/examples/ToneDetect1/ToneDetect1.ino
new file mode 100644
index 0000000..be115b2
--- /dev/null
+++ b/examples/ToneDetect1/ToneDetect1.ino
@@ -0,0 +1,62 @@
+/*
+ *  ToneDetect1.ino  Test the undecimated tone detector.
+ *
+ * Note that there is an alternative AudioAnalyzeCTCSS_F32
+ * tone detector for frequencies below a few hundred Hz.  This
+ * uses /16 decimation.
+ *
+ * This detector is suitable for DTMF  or similar tones.
+ *
+ * Bob Larkin 26 March 2021
+ * Rev 10 Mar 2022 to be compatible with CTCSS detector.
+ *
+ * Public Domain
+ */
+#include "OpenAudio_ArduinoLibrary.h"
+#include "AudioStream_F32.h"
+
+// T3.x supported sample rates: 2000, 8000, 11025, 16000, 22050, 24000, 32000, 44100, 44117, 48000,
+//                             88200, 88235 (44117*2), 95680, 96000, 176400, 176470, 192000
+// T4.x supports any sample rate the codec will handle.
+const float sample_rate_Hz = 44117.0f ;  // 24000, 44117, or other frequencies listed above (untested)
+const int   audio_block_samples = 128;   // Others untested
+AudioSettings_F32 audio_settings(sample_rate_Hz, audio_block_samples); // Not used, all at default
+
+AudioSynthWaveformSine_F32  sine1;
+AudioAnalyzeToneDetect_F32  toneDet1;
+AudioOutputI2S_F32       audioOutI2S1;
+AudioConnection_F32      patchCord3(sine1, toneDet1);
+
+float freq;
+
+void setup() {
+  Serial.begin(300);
+  delay(1000);
+  Serial.println("OpenAudio_ArduinoLibrary  - TestTone Detector");
+
+  AudioMemory_F32(20, audio_settings);
+
+  toneDet1.frequency(1209.0f, 24);
+  sine1.amplitude(1.0f);
+
+  // Plot the data from this loop to see the "sin(f)/f" response
+  for(freq=1000.0f; freq<=1400.0f; freq += 2.0f)
+      measureDataPoint();
+}
+
+void loop() {
+ }
+
+void measureDataPoint(void) {
+   sine1.frequency(freq);
+   // The toneDet1 is continuous.  But, if we change frequency, we need to
+   // wait at least 20 cycles at the tone detector frequency
+   // for the old measurements to flush through.  At 200 Hz toneDet1
+   // frequency, that would be 100 mSec.  Thus, 120 msec should be enough.
+   delay(120);
+   if( toneDet1.available() )  {
+      Serial.print(freq, 2);
+      Serial.print(",");
+      Serial.println(20.0f*log10f(toneDet1.read()), 6);
+      }
+  }