Revert "remove some constructors"

This reverts commit f07049c24e.

src/MFRC522.cpp

@@ -10,13 +10,26 @@
 /////////////////////////////////////////////////////////////////////////////////////
 // Functions for setting up the Arduino
 /////////////////////////////////////////////////////////////////////////////////////
+/**
+ * Constructor.
+ */
+MFRC522::MFRC522(): MFRC522(SS, UINT8_MAX) { // SS is defined in pins_arduino.h, UINT8_MAX means there is no connection from Arduino to MFRC522's reset and power down input
+} // End constructor
+
+/**
+ * Constructor.
+ * Prepares the output pins.
+ */
+MFRC522::MFRC522(	byte resetPowerDownPin	///< Arduino pin connected to MFRC522's reset and power down input (Pin 6, NRSTPD, active low). If there is no connection from the CPU to NRSTPD, set this to UINT8_MAX. In this case, only soft reset will be used in PCD_Init().
+				): MFRC522(SS, resetPowerDownPin) { // SS is defined in pins_arduino.h
+} // End constructor
 
 /**
  * Constructor.
  * Prepares the output pins.
  */
 MFRC522::MFRC522(	byte chipSelectPin,		///< Arduino pin connected to MFRC522's SPI slave select input (Pin 24, NSS, active low)
-					byte resetPowerDownPin	///< Arduino pin connected to MFRC522's reset and power down input (Pin 6, NRSTPD, active low). If there is no connection from the CPU to NRSTPD, set this to constant UNUSED_PIN. In this case, only soft reset will be used in PCD_Init().
+					byte resetPowerDownPin	///< Arduino pin connected to MFRC522's reset and power down input (Pin 6, NRSTPD, active low). If there is no connection from the CPU to NRSTPD, set this to UINT8_MAX. In this case, only soft reset will be used in PCD_Init().
 				) {
 	_chipSelectPin = chipSelectPin;
 	_resetPowerDownPin = resetPowerDownPin;
@@ -221,6 +234,14 @@ void MFRC522::PCD_Init() {
 	PCD_AntennaOn();						// Enable the antenna driver pins TX1 and TX2 (they were disabled by the reset)
 } // End PCD_Init()
 
+/**
+ * Initializes the MFRC522 chip.
+ */
+void MFRC522::PCD_Init(	byte resetPowerDownPin	///< Arduino pin connected to MFRC522's reset and power down input (Pin 6, NRSTPD, active low)
+					) {
+	PCD_Init(SS, resetPowerDownPin); // SS is defined in pins_arduino.h
+} // End PCD_Init()
+
 /**
  * Initializes the MFRC522 chip.
  */

src/MFRC522.h

@@ -144,7 +144,7 @@ public:
 	static constexpr byte FIFO_SIZE = 64;		// The FIFO is 64 bytes.
 	// Default value for unused pin
 	static constexpr uint8_t UNUSED_PIN = UINT8_MAX;
-	
+
 	// MFRC522 registers. Described in chapter 9 of the datasheet.
 	// When using SPI all addresses are shifted one bit left in the "SPI address byte" (section 8.1.2.3)
 	enum PCD_Register : byte {
@@ -332,7 +332,9 @@ public:
 	/////////////////////////////////////////////////////////////////////////////////////
 	// Functions for setting up the Arduino
 	/////////////////////////////////////////////////////////////////////////////////////
-	MFRC522() : MFRC522(UNUSED_PIN, UNUSED_PIN) {};
+	MFRC522();
+	DEPRECATED_MSG("use MFRC522(byte chipSelectPin, byte resetPowerDownPin)")
+	MFRC522(byte resetPowerDownPin);
 	MFRC522(byte chipSelectPin, byte resetPowerDownPin);
 	
 	/////////////////////////////////////////////////////////////////////////////////////
@@ -350,6 +352,8 @@ public:
 	// Functions for manipulating the MFRC522
 	/////////////////////////////////////////////////////////////////////////////////////
 	void PCD_Init();
+	DEPRECATED_MSG("use PCD_Init(byte chipSelectPin, byte resetPowerDownPin)")
+	void PCD_Init(byte resetPowerDownPin);
 	void PCD_Init(byte chipSelectPin, byte resetPowerDownPin);
 	void PCD_Reset();
 	void PCD_AntennaOn();

src/MFRC522Extended.h

@@ -78,6 +78,7 @@ public:
 	// Contructors
 	/////////////////////////////////////////////////////////////////////////////////////
 	MFRC522Extended() : MFRC522() {};
+	MFRC522Extended(uint8_t rst) : MFRC522(rst) {};
 	MFRC522Extended(uint8_t ss, uint8_t rst) : MFRC522(ss, rst) {};
 	
 	/////////////////////////////////////////////////////////////////////////////////////