Allow I2S constructor to set pins, like PWMAudio (#2702)

Pins are a physical connection, makes sense to define them at construction.

Author: earlephilhower

libraries/I2S/examples/SimpleTone/SimpleTone.ino

@@ -19,14 +19,14 @@
 
 #include <I2S.h>
 
-// Create the I2S port using a PIO state machine
-I2S i2s(OUTPUT);
-
 // GPIO pin numbers
 #define pBCLK 20
 #define pWS (pBCLK+1)
 #define pDOUT 22
 
+// Create the I2S port using a PIO state machine
+I2S i2s(OUTPUT, pBCLK, pDOUT);
+
 const int frequency = 440; // frequency of square wave in Hz
 const int amplitude = 500; // amplitude of square wave
 const int sampleRate = 16000; // minimum for UDA1334A
@@ -43,8 +43,6 @@ void setup() {
   Serial.begin(115200);
   Serial.println("I2S simple tone");
 
-  i2s.setBCLK(pBCLK);
-  i2s.setDATA(pDOUT);
   i2s.setBitsPerSample(16);
 
   // start I2S at the sample rate with 16-bits per sample

libraries/I2S/src/I2S.cpp

@@ -24,14 +24,14 @@
 #include <pico/stdlib.h>
 
 
-I2S::I2S(PinMode direction) {
+I2S::I2S(PinMode direction, pin_size_t bclk, pin_size_t data, pin_size_t mclk) {
     _running = false;
     _bps = 16;
     _writtenHalf = false;
     _isOutput = direction == OUTPUT;
-    _pinBCLK = 26;
-    _pinDOUT = 28;
-    _pinMCLK = 25;
+    _pinBCLK = bclk;
+    _pinDOUT = data;
+    _pinMCLK = mclk;
     _MCLKenabled = false;
 #ifdef PIN_I2S_BCLK
     _pinBCLK = PIN_I2S_BCLK;

libraries/I2S/src/I2S.h

@@ -25,7 +25,7 @@
 
 class I2S : public Stream {
 public:
-    I2S(PinMode direction = OUTPUT);
+    I2S(PinMode direction = OUTPUT, pin_size_t bclk = 26, pin_size_t data = 28, pin_size_t mclk = 25);
     virtual ~I2S();
 
     bool setBCLK(pin_size_t pin);