libs/RFID.MFRC522
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removed need for reset pin (#275)

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* removed need for reset pin - use soft reset on PCD_Init() if reset pin has not been configured
* UINT8_MAX is used to signify an unused reset connection, the  _resetPowerDownPin member is initialized accordingly
This commit is contained in:
Thorsten Köster
2017-02-22 15:47:42 +01:00
committed by Rotzbua
parent 12a00174b5
commit 637e81caba
1 changed files with 26 additions and 15 deletions
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41
MFRC522.cpp
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@@ -13,14 +13,14 @@
/**
* Constructor.
*/
MFRC522::MFRC522() {
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)
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
@@ -29,7 +29,7 @@ MFRC522::MFRC522( byte resetPowerDownPin ///< Arduino pin connected to MFRC522's
* 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)
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;
@@ -191,19 +191,26 @@ MFRC522::StatusCode MFRC522::PCD_CalculateCRC( byte *data, ///< In: Pointer to
* Initializes the MFRC522 chip.
*/
void MFRC522::PCD_Init() {
bool hardReset = false;
// Set the chipSelectPin as digital output, do not select the slave yet
pinMode(_chipSelectPin, OUTPUT);
digitalWrite(_chipSelectPin, HIGH);
// Set the resetPowerDownPin as digital output, do not reset or power down.
pinMode(_resetPowerDownPin, OUTPUT);
// If a valid pin number has been set, pull device out of power down / reset state.
if (_resetPowerDownPin != UINT8_MAX) {
// Set the resetPowerDownPin as digital output, do not reset or power down.
pinMode(_resetPowerDownPin, OUTPUT);
if (digitalRead(_resetPowerDownPin) == LOW) { //The MFRC522 chip is in power down mode.
digitalWrite(_resetPowerDownPin, HIGH); // Exit power down mode. This triggers a hard reset.
// Section 8.8.2 in the datasheet says the oscillator start-up time is the start up time of the crystal + 37,74μs. Let us be generous: 50ms.
delay(50);
if (digitalRead(_resetPowerDownPin) == LOW) { // The MFRC522 chip is in power down mode.
digitalWrite(_resetPowerDownPin, HIGH); // Exit power down mode. This triggers a hard reset.
// Section 8.8.2 in the datasheet says the oscillator start-up time is the start up time of the crystal + 37,74μs. Let us be generous: 50ms.
delay(50);
hardReset = true;
}
}
else { // Perform a soft reset
if (!hardReset) { // Perform a soft reset if we haven't triggered a hard reset above.
PCD_Reset();
}
@@ -455,11 +462,11 @@ MFRC522::StatusCode MFRC522::PCD_CommunicateWithPICC( byte command, ///< The co
byte errorRegValue = PCD_ReadRegister(ErrorReg); // ErrorReg[7..0] bits are: WrErr TempErr reserved BufferOvfl CollErr CRCErr ParityErr ProtocolErr
if (errorRegValue & 0x13) { // BufferOvfl ParityErr ProtocolErr
return STATUS_ERROR;
}
byte _validBits;
}
byte _validBits = 0;
// If the caller wants data back, get it from the MFRC522.
// If the caller wants data back, get it from the MFRC522.
if (backData && backLen) {
byte n = PCD_ReadRegister(FIFOLevelReg); // Number of bytes in the FIFO
if (n > *backLen) {
@@ -1139,6 +1146,9 @@ MFRC522::StatusCode MFRC522::MIFARE_SetValue(byte blockAddr, int32_t value) {
*/
MFRC522::StatusCode MFRC522::PCD_NTAG216_AUTH(byte* passWord, byte pACK[]) //Authenticate with 32bit password
{
// TODO: Fix cmdBuffer length and rxlength. They really should match.
// (Better still, rxlength should not even be necessary.)
MFRC522::StatusCode result;
byte cmdBuffer[18]; // We need room for 16 bytes data and 2 bytes CRC_A.
@@ -1155,7 +1165,7 @@ MFRC522::StatusCode MFRC522::PCD_NTAG216_AUTH(byte* passWord, byte pACK[]) //Aut
// Transceive the data, store the reply in cmdBuffer[]
byte waitIRq = 0x30; // RxIRq and IdleIRq
byte cmdBufferSize = sizeof(cmdBuffer);
// byte cmdBufferSize = sizeof(cmdBuffer);
byte validBits = 0;
byte rxlength = 5;
result = PCD_CommunicateWithPICC(PCD_Transceive, waitIRq, cmdBuffer, 7, cmdBuffer, &rxlength, &validBits);
@@ -1475,6 +1485,7 @@ void MFRC522::PICC_DumpMifareClassicSectorToSerial(Uid *uid, ///< Pointer to U
byte buffer[18];
byte blockAddr;
isSectorTrailer = true;
invertedError = false; // Avoid "unused variable" warning.
for (int8_t blockOffset = no_of_blocks - 1; blockOffset >= 0; blockOffset--) {
blockAddr = firstBlock + blockOffset;
// Sector number - only on first line