made fix to the ESP32 I2S simple tone example

libraries/ESP_I2S/examples/Simple_tone/Simple_tone.ino

@@ -24,10 +24,17 @@
  2nd September 2021
  Lucas Saavedra Vaz (lucasssvaz)
  22nd December 2023
+ anon
+ 10nd February 2025
  */
 
 #include <ESP_I2S.h>
 
+// The GPIO pins are not fixed, most other pins can be used for the I2S function.
+#define I2S_LRC 25
+#define I2S_BCLK 5
+#define I2S_DIN 26
+
 const int frequency = 440;    // frequency of square wave in Hz
 const int amplitude = 500;    // amplitude of square wave
 const int sampleRate = 8000;  // sample rate in Hz
@@ -36,21 +43,24 @@ i2s_data_bit_width_t bps = I2S_DATA_BIT_WIDTH_16BIT;
 i2s_mode_t mode = I2S_MODE_STD;
 i2s_slot_mode_t slot = I2S_SLOT_MODE_STEREO;
 
-const int halfWavelength = (sampleRate / frequency);  // half wavelength of square wave
+const int halfWavelength = sampleRate / frequency / 2;  // half wavelength of square wave
 
 int32_t sample = amplitude;  // current sample value
-int count = 0;
+unsigned int count = 0;
 
 I2SClass i2s;
 
 void setup() {
   Serial.begin(115200);
   Serial.println("I2S simple tone");
 
+  i2s.setPins(I2S_BCLK, I2S_LRC, I2S_DIN);
+
   // start I2S at the sample rate with 16-bits per sample
   if (!i2s.begin(mode, sampleRate, bps, slot)) {
     Serial.println("Failed to initialize I2S!");
-    while (1);  // do nothing
+    while (1)
+      ;  // do nothing
   }
 }
 
@@ -60,8 +70,13 @@ void loop() {
     sample = -1 * sample;
   }
 
-  i2s.write(sample);  // Right channel
-  i2s.write(sample);  // Left channel
+  // Right channel, low 8 bit then hight 8 bit
+  i2s.write(sample);
+  i2s.write(sample >> 8);
+
+  // Left channel, low 8 bit then hight 8 bit
+  i2s.write(sample);
+  i2s.write(sample >> 8);
 
   // increment the counter for the next sample
   count++;