From 59acb746aeeb57bf51aeddc61a0b9ae0430abbe9 Mon Sep 17 00:00:00 2001
From: boblark <bob@janbob.com>
Date: Fri, 13 Jan 2023 15:21:08 -0800
Subject: [PATCH] Minor corrections for playing WAV files from SD cards

---
 AudioSDPlayer_F32.cpp                |   4 +-
 docs/index.html                      | 117 +++++++++++++++++++++++++++
 examples/SDWavPlayer/SDWavPlayer.ino |  36 ++++-----
 3 files changed, 136 insertions(+), 21 deletions(-)

diff --git a/AudioSDPlayer_F32.cpp b/AudioSDPlayer_F32.cpp
index 032443a..8fbd229 100644
--- a/AudioSDPlayer_F32.cpp
+++ b/AudioSDPlayer_F32.cpp
@@ -630,7 +630,7 @@ bool AudioSDPlayer_F32::parse_format(void) {
 
     rate = header[1];
     currentWavData.sample_rate = header[1];    // uint32_t
-    Serial.print("WAV file sample rate = ");  Serial.println(rate);
+    // Serial.print("WAV file sample rate = ");  Serial.println(rate);
 
     // b2m is used to determine playing time.  We base it on the WAV
     // file meta data.  It is allowed to be played at a different rate
@@ -665,7 +665,7 @@ bool AudioSDPlayer_F32::parse_format(void) {
     else {return false;}
 
     bytes2millis = b2m;   // Transfer to global
-    Serial.print("  bytes2millis = "); Serial.println(b2m);
+    // Serial.print("  bytes2Millis = "); Serial.println(b2m);
     // we're not checking the byte rate and block align fields
     // if they're not the expected values, all we could do is
     // return false.  Do any real wav files have unexpected
diff --git a/docs/index.html b/docs/index.html
index 11ef03b..249fb39 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -391,6 +391,7 @@ span.mainfunction {color: #993300; font-weight: bolder}
         {"type":"AudioMathScale_F32","data":{"defaults":{"name":{"value":"new"}},"shortName":"mathScale","inputs":"1","output":"0","category":"math-function","color":"#E6E0F8","icon":"arrow-in.png","outputs":"1"}},
         {"type":"AudioMixer4_F32","data":{"defaults":{"name":{"value":"new"}},"shortName":"mixer4","inputs":"4","output":"0","category":"mixer-function","color":"#E6E0F8","icon":"arrow-in.png","outputs":"1"}},
         {"type":"AudioMixer8_F32","data":{"defaults":{"name":{"value":"new"}},"shortName":"mixer8","inputs":"8","output":"0","category":"mixer-function","color":"#E6E0F8","icon":"arrow-in.png","outputs":"1"}},
+	    {"type":"AudioPlaySdWav_F32","data":{"defaults":{"name":{"value":"new"}},"shortName":"playSdWav","inputs":0,"outputs":2,"category":"play-function","color":"#E6E0F8","icon":"arrow-in.png","outputs":"2"}},
         {"type":"AudioSwitch4_OA_F32","data":{"defaults":{"name":{"value":"new"}},"shortName":"switch4","inputs":"1","output":"0","category":"mixer-function","color":"#E6E0F8","icon":"arrow-in.png","outputs":"4"}},
         {"type":"AudioSwitch8_OA_F32","data":{"defaults":{"name":{"value":"new"}},"shortName":"switch8","inputs":"1","output":"0","category":"mixer-function","color":"#E6E0F8","icon":"arrow-in.png","outputs":"8"}},
         {"type":"FFT_Overlapped_F32","data":{"defaults":{"name":{"value":"new"}},"shortName":"blockwiseFFT","inputs":"NaN","output":"0","category":"analyze-function","color":"#E6E0F8","icon":"arrow-in.png","outputs":"NaN"}},
@@ -2558,6 +2559,122 @@ look ahead delay, as well.</p>
     </div>
 </script>
 
+
+<script type="text/x-red" data-help-name="AudioPlaySdWav_F32">
+	<h3>Summary</h3>
+	<div class=tooltipinfo>
+	<p>Plays a WAV file, stored on an SD card.</p>
+	</div>
+	<h3>Audio Connections</h3>
+	<table class=doc align=center cellpadding=3>
+		<tr class=top><th>Port</th><th>Purpose</th></tr>
+		<tr class=odd><td align=center>Out 0</td><td>Left Channel Output</td></tr>
+		<tr class=odd><td align=center>Out 1</td><td>Right Channel Output</td></tr>
+	</table>
+	<h3>Functions</h3>
+	<p class=func><span class=keyword>play</span>(filename);</p>
+	<p class=desc>Begin playing a WAV file.  If a file is already playing,
+		it is stopped and this file starts playing from the beginning.
+	    No return value.</p>
+	<p class=func><span class=keyword>stop</span>();</p>
+	<p class=desc>Stop playing.  If not playing, this function has no effect.
+	    No return value.</p>
+
+	<p class=func><span class=keyword>togglePlayPause</span>();</p>
+	<p class=desc>Used to Pause the playing of a file, or to un-Pause
+	   depending on which applies. No return value. </p>
+
+	<p class=func><span class=keyword>isPlaying</span>();</p>
+	<p class=desc>Return true (non-zero) if playing, or false (zero)
+		when not playing.  See the note below about delayed start.</p>
+
+	<p class=func><span class=keyword>isPaused</span>();</p>
+	<p class=desc>Return true (non-zero) if paused (see
+	   togglePlayPause above).
+
+	<p class=func><span class=keyword>isStopped</span>();</p>
+	<p class=desc>Return true (non-zero) if not playing and
+	   not paused.</p>
+
+
+	<p class=func><span class=keyword>setSubMult</span>(subMult* pStruct)
+	</span>();</p>
+	<p class=desc>Used if the WAV file is to be run at a lower sample rate
+	    than the audio sample rate.  The two rates must be related by an integer.
+	    The calling parameter is a pointer to a structure of type subMult.
+	    That is defined as:
+	<pre>
+    struct subMult {
+        uint16_t   rateRatio;   // Should be 1 for no rate change, else an integer
+        uint16_t   numCoeffs;   // FIR filter
+        float32_t* firCoeffs;   // FIR Filter Coeffs
+        float32_t* firBufferL;  // pointer to 127 + numCoeffs float32_t, left ch
+        float32_t* firBufferR;  // pointer to 127 + numCoeffs float32_t, right ch
+        };</pre>
+        The struct is declared in the INO and this function transmits the selected
+        information.  Note  that the FIR filters can be used, even if the rateRatio
+        is 1.  There is no need for this caused by rateRatio = 1, but
+        the filter function may be useful for other reasons.  If the WAV file
+        and the Audio are both using the same sample rate, this function
+        is not needed and the rateRatio defaults to 1 and no FIR filters
+        are involked.  The left and right FIR filters use the same coefficients
+        but need separate firBuffer.  For monaural files, the firBufferR pointer can be
+        a NULL.</p>
+
+	<p class=func><span class=keyword>getCurrentWavData</span>();</p>
+		This returns a pointer to a structure containing data about the
+		WAV file currently selected for play.  The structure is:
+		<pre>
+	struct wavData {
+        uint16_t audio_format;  // Should be 1 for PCM
+        uint16_t num_channels;  // 1 for mono, 2 for stereo
+        uint32_t sample_rate;   // 44100, 48000, etc
+        uint16_t bits;          // Number of bits per sample, should be 16
+        };</pre>
+	</p>
+	<p class=func><span class=keyword>positionMillis</span>();</p>
+	<p class=desc>While playing, return the current time offset, in
+		milliseconds.  When not playing, the return from this function
+		is undefined.
+	</p>
+	<p class=func><span class=keyword>lengthMillis</span>();</p>
+	<p class=desc>Return the total length of the current sound clip,
+		in milliseconds.  When not playing, the return from this function
+		is undefined.
+	</p>
+	<h3>Examples</h3>
+	<p class=exam>File &gt; Examples &gt; Audio &gt; WavFilePlayer
+	<p class=exam>File &gt; Examples &gt; Audio &gt; WavFilePlayer2
+	</p>
+	<h3>Notes</h3>
+	<p>Only 16 bit PCM WAV files are supported.  When mono
+		files are played, both output ports transmit a copy of the
+		single sound.  Of course, stereo WAV files play with the left
+		channel on port 0 and the right channel on port 1.
+	</p>
+	<p>A brief delay after calling play() will usually occur before
+		isPlaying() returns true and positionMillis() returns valid
+		time offset.  WAV files have a header at the beginning of the
+		file, which the audio library must read and parse before
+		playing can begin.
+	</p>
+	<p>While playing, the audio library accesses the SD card automatically.
+		If card access is needed for other purposes, you must
+		<a href="http://www.pjrc.com/teensy/td_libs_AudioProcessorUsage.html"
+		    target="_blank">use AudioNoInterrupts()</a>
+		to prevent AudioPlaySDWav from accessing the SD card while you use it.
+		Disabling the audio library interrupt for too long may cause audible
+		dropouts or glitches.
+	</p>
+
+</script>
+<script type="text/x-red" data-template-name="AudioPlaySdWav_F32">
+	<div class="form-row">
+		<label for="node-input-name"><i class="fa fa-tag"></i> Name</label>
+		<input type="text" id="node-input-name" placeholder="Name">
+	</div>
+</script>
+
 <script type="text/x-red" data-help-name="AudioPlayQueue_F32">
     <h3>Summary</h3>
     <div class=tooltipinfo>
diff --git a/examples/SDWavPlayer/SDWavPlayer.ino b/examples/SDWavPlayer/SDWavPlayer.ino
index a1f81e9..67dea53 100644
--- a/examples/SDWavPlayer/SDWavPlayer.ino
+++ b/examples/SDWavPlayer/SDWavPlayer.ino
@@ -4,7 +4,10 @@
  * Created: Chip Audette, OpenAudio, Dec 2019
  * Based On: WaveFilePlayer from Paul Stoffregen, PJRC, Teensy
  *
- * Play back a WAV file through the Typman.
+ * Play back a WAV file
+ *
+ * This is the basic WAV file player, adapted from the Tympan library.
+ * See also WAVFilePlayer and WAVFilePlayer2     Bob
  *
  * For access to WAV files, please visit https://www.pjrc.com/teensy/td_libs_AudioDataFiles.html.
  *
@@ -21,14 +24,12 @@ AudioSettings_F32 audio_settings(sample_rate_Hz, audio_block_samples);
 //create audio objects
 AudioSDPlayer_F32        audioSDPlayer(audio_settings);
 AudioOutputI2S_F32       audioOutput(audio_settings);
-//Tympan                   myTympan(TympanRev::E); //do TympanRev::D or TympanRev::E
 
 //create audio connections
 AudioConnection_F32      patchCord1(audioSDPlayer, 0, audioOutput, 0);
 AudioConnection_F32      patchCord2(audioSDPlayer, 1, audioOutput, 1);
 AudioControlSGTL5000     sgtl5000_1;
 
-
 // Use these with the Teensy 4.x Rev D Audio Shield
 #define SDCARD_CS_PIN   10
 #define SDCARD_MOSI_PIN 11
@@ -36,14 +37,17 @@ AudioControlSGTL5000     sgtl5000_1;
 
 void setup() {
   Serial.begin(300); delay(1000);
-  Serial.print("### SDWavPlayer ###");
-  Serial.print("Sample Rate (Hz): "); Serial.println(audio_settings.sample_rate_Hz);
-  Serial.print("Audio Block Size (samples): "); Serial.println(audio_settings.audio_block_samples);
+  Serial.println("###  SDWavPlayer  ###");
+  Serial.print("Audio Sample Rate (Hz): ");
+  Serial.println(audio_settings.sample_rate_Hz);
+  Serial.print("Audio Block Size (samples): ");
+  Serial.println(audio_settings.audio_block_samples);
 
   // Audio connections require memory to work.
   AudioMemory_F32(20, audio_settings);
 
   sgtl5000_1.enable();
+  audioOutput.setGain(0.05);  // Volume control
 
   SPI.setMOSI(SDCARD_MOSI_PIN);
   SPI.setSCK(SDCARD_SCK_PIN);
@@ -58,23 +62,17 @@ void setup() {
   audioSDPlayer.begin();
 
   //finish setup
-  delay(2000);  //stall a second
+  delay(1000);  //stall a second
   Serial.println("Setup complete.");
 }
 
-unsigned long end_millis = 0;
-String filename = "SDTEST1.WAV";// filenames are always uppercase 8.3 format
 void loop() {
-
-/*
   //service the audio player
-  if (!audioSDPlayer.isPlaying()) { //wait until previous play is done
-    //start playing audio
-    Serial.print("Starting audio player: ");
-    Serial.println(filename);
-    audioSDPlayer.play(filename);
-  }
- */
-
+  if (!audioSDPlayer.isPlaying())
+     { //wait until previous play is done
+     //start playing audio
+     Serial.println("Starting audio player: SDTEST1.WAV");
+     audioSDPlayer.play("SDTEST1.WAV");
+     }
   delay(500);
 }