MFRC522.h

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// Copyright (C) 2021 twyleg
#pragma once
 
#include "bcm2835/ispi.h"
#include "bcm2835/igpio.h"
 
#include <stdint.h>
#include <stdio.h>
#include <string>
 
namespace mfrc522 {
 
using namespace std;
 
typedef uint16_t word;
 
// Firmware data for self-test
// Reference values based on firmware version; taken from 16.1.1 in spec.
// Version 1.0
 
const uint8_t MFRC522_firmware_referenceV1_0[]  = {
    0x00, 0xC6, 0x37, 0xD5, 0x32, 0xB7, 0x57, 0x5C,
    0xC2, 0xD8, 0x7C, 0x4D, 0xD9, 0x70, 0xC7, 0x73,
    0x10, 0xE6, 0xD2, 0xAA, 0x5E, 0xA1, 0x3E, 0x5A,
    0x14, 0xAF, 0x30, 0x61, 0xC9, 0x70, 0xDB, 0x2E,
    0x64, 0x22, 0x72, 0xB5, 0xBD, 0x65, 0xF4, 0xEC,
    0x22, 0xBC, 0xD3, 0x72, 0x35, 0xCD, 0xAA, 0x41,
    0x1F, 0xA7, 0xF3, 0x53, 0x14, 0xDE, 0x7E, 0x02,
    0xD9, 0x0F, 0xB5, 0x5E, 0x25, 0x1D, 0x29, 0x79
};
 
// Version 2.0
const uint8_t MFRC522_firmware_referenceV2_0[] = {
    0x00, 0xEB, 0x66, 0xBA, 0x57, 0xBF, 0x23, 0x95,
    0xD0, 0xE3, 0x0D, 0x3D, 0x27, 0x89, 0x5C, 0xDE,
    0x9D, 0x3B, 0xA7, 0x00, 0x21, 0x5B, 0x89, 0x82,
    0x51, 0x3A, 0xEB, 0x02, 0x0C, 0xA5, 0x00, 0x49,
    0x7C, 0x84, 0x4D, 0xB3, 0xCC, 0xD2, 0x1B, 0x81,
    0x5D, 0x48, 0x76, 0xD5, 0x71, 0x61, 0x21, 0xA9,
    0x86, 0x96, 0x83, 0x38, 0xCF, 0x9D, 0x5B, 0x6D,
    0xDC, 0x15, 0xBA, 0x3E, 0x7D, 0x95, 0x3B, 0x2F
};
 
 
 
class MFRC522 {
public:
    // MFRC522 registers. Described in chapter 9 of the datasheet.
    // When using SPI all addresses are shifted one bit left in the "SPI address uint8_t" (section 8.1.2.3)
    enum PCD_Register {
        // Page 0: Command and status
        //                        0x00          // reserved for future use
        CommandReg              = 0x01 << 1,    // starts and stops command execution
        ComIEnReg               = 0x02 << 1,    // enable and disable interrupt request control bits
        DivIEnReg               = 0x03 << 1,    // enable and disable interrupt request control bits
        ComIrqReg               = 0x04 << 1,    // interrupt request bits
        DivIrqReg               = 0x05 << 1,    // interrupt request bits
        ErrorReg                = 0x06 << 1,    // error bits showing the error status of the last command executed
        Status1Reg              = 0x07 << 1,    // communication status bits
        Status2Reg              = 0x08 << 1,    // receiver and transmitter status bits
        FIFODataReg             = 0x09 << 1,    // input and output of 64 byte FIFO buffer
        FIFOLevelReg            = 0x0A << 1,    // number of bytes stored in the FIFO buffer
        WaterLevelReg           = 0x0B << 1,    // level for FIFO underflow and overflow warning
        ControlReg              = 0x0C << 1,    // miscellaneous control registers
        BitFramingReg           = 0x0D << 1,    // adjustments for bit-oriented frames
        CollReg                 = 0x0E << 1,    // bit position of the first bit-collision detected on the RF interface
        //                        0x0F          // reserved for future use
 
        // Page 1: Command
        //                        0x10          // reserved for future use
        ModeReg                 = 0x11 << 1,    // defines general modes for transmitting and receiving
        TxModeReg               = 0x12 << 1,    // defines transmission data rate and framing
        RxModeReg               = 0x13 << 1,    // defines reception data rate and framing
        TxControlReg            = 0x14 << 1,    // controls the logical behavior of the antenna driver pins TX1 and TX2
        TxASKReg                = 0x15 << 1,    // controls the setting of the transmission modulation
        TxSelReg                = 0x16 << 1,    // selects the internal sources for the antenna driver
        RxSelReg                = 0x17 << 1,    // selects internal receiver settings
        RxThresholdReg          = 0x18 << 1,    // selects thresholds for the bit decoder
        DemodReg                = 0x19 << 1,    // defines demodulator settings
        //                        0x1A          // reserved for future use
        //                        0x1B          // reserved for future use
        MfTxReg                 = 0x1C << 1,    // controls some MIFARE communication transmit parameters
        MfRxReg                 = 0x1D << 1,    // controls some MIFARE communication receive parameters
        //                        0x1E          // reserved for future use
        SerialSpeedReg          = 0x1F << 1,    // selects the speed of the serial UART interface
 
        // Page 2: Configuration
        //                        0x20          // reserved for future use
        CRCResultRegH           = 0x21 << 1,    // shows the MSB and LSB values of the CRC calculation
        CRCResultRegL           = 0x22 << 1,
        //                        0x23          // reserved for future use
        ModWidthReg             = 0x24 << 1,    // controls the ModWidth setting?
        //                        0x25          // reserved for future use
        RFCfgReg                = 0x26 << 1,    // configures the receiver gain
        GsNReg                  = 0x27 << 1,    // selects the conductance of the antenna driver pins TX1 and TX2 for modulation
        CWGsPReg                = 0x28 << 1,    // defines the conductance of the p-driver output during periods of no modulation
        ModGsPReg               = 0x29 << 1,    // defines the conductance of the p-driver output during periods of modulation
        TModeReg                = 0x2A << 1,    // defines settings for the internal timer
        TPrescalerReg           = 0x2B << 1,    // the lower 8 bits of the TPrescaler value. The 4 high bits are in TModeReg.
        TReloadRegH             = 0x2C << 1,    // defines the 16-bit timer reload value
        TReloadRegL             = 0x2D << 1,
        TCounterValueRegH       = 0x2E << 1,    // shows the 16-bit timer value
        TCounterValueRegL       = 0x2F << 1,
 
        // Page 3: Test Registers
        //                        0x30          // reserved for future use
        TestSel1Reg             = 0x31 << 1,    // general test signal configuration
        TestSel2Reg             = 0x32 << 1,    // general test signal configuration
        TestPinEnReg            = 0x33 << 1,    // enables pin output driver on pins D1 to D7
        TestPinValueReg         = 0x34 << 1,    // defines the values for D1 to D7 when it is used as an I/O bus
        TestBusReg              = 0x35 << 1,    // shows the status of the internal test bus
        AutoTestReg             = 0x36 << 1,    // controls the digital self test
        VersionReg              = 0x37 << 1,    // shows the software version
        AnalogTestReg           = 0x38 << 1,    // controls the pins AUX1 and AUX2
        TestDAC1Reg             = 0x39 << 1,    // defines the test value for TestDAC1
        TestDAC2Reg             = 0x3A << 1,    // defines the test value for TestDAC2
        TestADCReg              = 0x3B << 1     // shows the value of ADC I and Q channels
        //                        0x3C          // reserved for production tests
        //                        0x3D          // reserved for production tests
        //                        0x3E          // reserved for production tests
        //                        0x3F          // reserved for production tests
    };
 
    // MFRC522 commands. Described in chapter 10 of the datasheet.
    enum PCD_Command {
        PCD_Idle                = 0x00,     // no action, cancels current command execution
        PCD_Mem                 = 0x01,     // stores 25 bytes into the internal buffer
        PCD_GenerateRandomID    = 0x02,     // generates a 10-byte random ID number
        PCD_CalcCRC             = 0x03,     // activates the CRC coprocessor or performs a self test
        PCD_Transmit            = 0x04,     // transmits data from the FIFO buffer
        PCD_NoCmdChange         = 0x07,     // no command change, can be used to modify the CommandReg register bits without affecting the command, for example, the PowerDown bit
        PCD_Receive             = 0x08,     // activates the receiver circuits
        PCD_Transceive          = 0x0C,     // transmits data from FIFO buffer to antenna and automatically activates the receiver after transmission
        PCD_MFAuthent           = 0x0E,     // performs the MIFARE standard authentication as a reader
        PCD_SoftReset           = 0x0F      // resets the MFRC522
    };
 
    // MFRC522 RxGain[2:0] masks, defines the receiver's signal voltage gain factor (on the PCD).
    // Described in 9.3.3.6 / table 98 of the datasheet at http://www.nxp.com/documents/data_sheet/MFRC522.pdf
    enum PCD_RxGain {
        RxGain_18dB             = 0x00 << 4,    // 000b - 18 dB, minimum
        RxGain_23dB             = 0x01 << 4,    // 001b - 23 dB
        RxGain_18dB_2           = 0x02 << 4,    // 010b - 18 dB, it seems 010b is a duplicate for 000b
        RxGain_23dB_2           = 0x03 << 4,    // 011b - 23 dB, it seems 011b is a duplicate for 001b
        RxGain_33dB             = 0x04 << 4,    // 100b - 33 dB, average, and typical default
        RxGain_38dB             = 0x05 << 4,    // 101b - 38 dB
        RxGain_43dB             = 0x06 << 4,    // 110b - 43 dB
        RxGain_48dB             = 0x07 << 4,    // 111b - 48 dB, maximum
        RxGain_min              = 0x00 << 4,    // 000b - 18 dB, minimum, convenience for RxGain_18dB
        RxGain_avg              = 0x04 << 4,    // 100b - 33 dB, average, convenience for RxGain_33dB
        RxGain_max              = 0x07 << 4     // 111b - 48 dB, maximum, convenience for RxGain_48dB
    };
 
    // Commands sent to the PICC.
    enum PICC_Command {
        // The commands used by the PCD to manage communication with several PICCs (ISO 14443-3, Type A, section 6.4)
        PICC_CMD_REQA           = 0x26,     // REQuest command, Type A. Invites PICCs in state IDLE to go to READY and prepare for anticollision or selection. 7 bit frame.
        PICC_CMD_WUPA           = 0x52,     // Wake-UP command, Type A. Invites PICCs in state IDLE and HALT to go to READY(*) and prepare for anticollision or selection. 7 bit frame.
        PICC_CMD_CT             = 0x88,     // Cascade Tag. Not really a command, but used during anti collision.
        PICC_CMD_SEL_CL1        = 0x93,     // Anti collision/Select, Cascade Level 1
        PICC_CMD_SEL_CL2        = 0x95,     // Anti collision/Select, Cascade Level 2
        PICC_CMD_SEL_CL3        = 0x97,     // Anti collision/Select, Cascade Level 3
        PICC_CMD_HLTA           = 0x50,     // HaLT command, Type A. Instructs an ACTIVE PICC to go to state HALT.
        // The commands used for MIFARE Classic (from http://www.nxp.com/documents/data_sheet/MF1S503x.pdf, Section 9)
        // Use PCD_MFAuthent to authenticate access to a sector, then use these commands to read/write/modify the blocks on the sector.
        // The read/write commands can also be used for MIFARE Ultralight.
        PICC_CMD_MF_AUTH_KEY_A  = 0x60,     // Perform authentication with Key A
        PICC_CMD_MF_AUTH_KEY_B  = 0x61,     // Perform authentication with Key B
        PICC_CMD_MF_READ        = 0x30,     // Reads one 16 byte block from the authenticated sector of the PICC. Also used for MIFARE Ultralight.
        PICC_CMD_MF_WRITE       = 0xA0,     // Writes one 16 byte block to the authenticated sector of the PICC. Called "COMPATIBILITY WRITE" for MIFARE Ultralight.
        PICC_CMD_MF_DECREMENT   = 0xC0,     // Decrements the contents of a block and stores the result in the internal data register.
        PICC_CMD_MF_INCREMENT   = 0xC1,     // Increments the contents of a block and stores the result in the internal data register.
        PICC_CMD_MF_RESTORE     = 0xC2,     // Reads the contents of a block into the internal data register.
        PICC_CMD_MF_TRANSFER    = 0xB0,     // Writes the contents of the internal data register to a block.
        // The commands used for MIFARE Ultralight (from http://www.nxp.com/documents/data_sheet/MF0ICU1.pdf, Section 8.6)
        // The PICC_CMD_MF_READ and PICC_CMD_MF_WRITE can also be used for MIFARE Ultralight.
        PICC_CMD_UL_WRITE       = 0xA2      // Writes one 4 byte page to the PICC.
    };
 
    // MIFARE constants that does not fit anywhere else
    enum MIFARE_Misc {
        MF_ACK                  = 0xA,      // The MIFARE Classic uses a 4 bit ACK/NAK. Any other value than 0xA is NAK.
        MF_KEY_SIZE             = 6         // A Mifare Crypto1 key is 6 bytes.
    };
 
    // PICC types we can detect. Remember to update PICC_GetTypeName() if you add more.
    enum PICC_Type {
        PICC_TYPE_UNKNOWN       = 0,
        PICC_TYPE_ISO_14443_4   = 1,    // PICC compliant with ISO/IEC 14443-4
        PICC_TYPE_ISO_18092     = 2,    // PICC compliant with ISO/IEC 18092 (NFC)
        PICC_TYPE_MIFARE_MINI   = 3,    // MIFARE Classic protocol, 320 bytes
        PICC_TYPE_MIFARE_1K     = 4,    // MIFARE Classic protocol, 1KB
        PICC_TYPE_MIFARE_4K     = 5,    // MIFARE Classic protocol, 4KB
        PICC_TYPE_MIFARE_UL     = 6,    // MIFARE Ultralight or Ultralight C
        PICC_TYPE_MIFARE_PLUS   = 7,    // MIFARE Plus
        PICC_TYPE_TNP3XXX       = 8,    // Only mentioned in NXP AN 10833 MIFARE Type Identification Procedure
        PICC_TYPE_NOT_COMPLETE  = 255   // SAK indicates UID is not complete.
    };
 
    // Return codes from the functions in this class. Remember to update GetStatusCodeName() if you add more.
    enum StatusCode {
        STATUS_OK               = 1,    // Success
        STATUS_ERROR            = 2,    // Error in communication
        STATUS_COLLISION        = 3,    // Collission detected
        STATUS_TIMEOUT          = 4,    // Timeout in communication.
        STATUS_NO_ROOM          = 5,    // A buffer is not big enough.
        STATUS_INTERNAL_ERROR   = 6,    // Internal error in the code. Should not happen ;-)
        STATUS_INVALID          = 7,    // Invalid argument.
        STATUS_CRC_WRONG        = 8,    // The CRC_A does not match
        STATUS_MIFARE_NACK      = 9     // A MIFARE PICC responded with NAK.
    };
 
    // A struct used for passing the UID of a PICC.
    typedef struct {
        uint8_t     size;           // Number of bytes in the UID. 4, 7 or 10.
        uint8_t     uidByte[10];
        uint8_t     sak;            // The SAK (Select acknowledge) byte returned from the PICC after successful selection.
    } Uid;
 
    // A struct used for passing a MIFARE Crypto1 key
    typedef struct {
        uint8_t     keyByte[MF_KEY_SIZE];
    } MIFARE_Key;
 
    // Member variables
    Uid uid;                                // Used by PICC_ReadCardSerial().
 
    ISpi& mSpi;
    IGpio& mResetPin;
 
    // Size of the MFRC522 FIFO
    static const uint8_t FIFO_SIZE = 64;        // The FIFO is 64 bytes.
 
    // Functions for setting up the Raspberry Pi
    MFRC522(ISpi&, IGpio& resetPin);
    // Basic interface functions for communicating with the MFRC522
    void PCD_WriteRegister(uint8_t reg, uint8_t value);
    void PCD_WriteRegister(uint8_t reg, uint8_t count, uint8_t *values);
    uint8_t PCD_ReadRegister(uint8_t reg);
    void PCD_ReadRegister(uint8_t reg, uint8_t count, uint8_t *values, uint8_t rxAlign = 0);
    void setBitMask(unsigned char reg, unsigned char mask);
    void PCD_SetRegisterBitMask(uint8_t reg, uint8_t mask);
    void PCD_ClearRegisterBitMask(uint8_t reg, uint8_t mask);
    uint8_t PCD_CalculateCRC(uint8_t *data, uint8_t length, uint8_t *result);
 
    // Functions for manipulating the MFRC522
    void PCD_Init();
    void PCD_Reset();
    void PCD_AntennaOn();
    void PCD_AntennaOff();
    uint8_t PCD_GetAntennaGain();
    void PCD_SetAntennaGain(uint8_t mask);
    bool PCD_PerformSelfTest();
 
    // Functions for communicating with PICCs
    uint8_t PCD_TransceiveData(uint8_t *sendData, uint8_t sendLen, uint8_t *backData, uint8_t *backLen, uint8_t *validBits = NULL, uint8_t rxAlign = 0, bool checkCRC = false);
    uint8_t PCD_CommunicateWithPICC(uint8_t command, uint8_t waitIRq, uint8_t *sendData, uint8_t sendLen, uint8_t *backData = NULL, uint8_t *backLen = NULL, uint8_t *validBits = NULL, uint8_t rxAlign = 0, bool checkCRC = false);
    uint8_t PICC_RequestA(uint8_t *bufferATQA, uint8_t *bufferSize);
    uint8_t PICC_WakeupA(uint8_t *bufferATQA, uint8_t *bufferSize);
    uint8_t PICC_REQA_or_WUPA(uint8_t command, uint8_t *bufferATQA, uint8_t *bufferSize);
    uint8_t PICC_Select(Uid *uid, uint8_t validBits = 0);
    uint8_t PICC_HaltA();
 
    // Functions for communicating with MIFARE PICCs
    uint8_t PCD_Authenticate(uint8_t command, uint8_t blockAddr, MIFARE_Key *key, Uid *uid);
    void PCD_StopCrypto1();
    uint8_t MIFARE_Read(uint8_t blockAddr, uint8_t *buffer, uint8_t *bufferSize);
    uint8_t MIFARE_Write(uint8_t blockAddr, uint8_t *buffer, uint8_t bufferSize);
    uint8_t MIFARE_Decrement(uint8_t blockAddr, long delta);
    uint8_t MIFARE_Increment(uint8_t blockAddr, long delta);
    uint8_t MIFARE_Restore(uint8_t blockAddr);
    uint8_t MIFARE_Transfer(uint8_t blockAddr);
    uint8_t MIFARE_Ultralight_Write(uint8_t page, uint8_t *buffer, uint8_t bufferSize);
    uint8_t MIFARE_GetValue(uint8_t blockAddr, long *value);
    uint8_t MIFARE_SetValue(uint8_t blockAddr, long value);
 
    // Support functions
    uint8_t PCD_MIFARE_Transceive(uint8_t *sendData, uint8_t sendLen, bool acceptTimeout = false);
    // old function used too much memory, now name moved to flash; if you need char, copy from flash to memory
    //const char *GetStatusCodeName(uint8_t code);
    const string GetStatusCodeName(uint8_t code);
    uint8_t PICC_GetType(uint8_t sak);
    // old function used too much memory, now name moved to flash; if you need char, copy from flash to memory
    //const char *PICC_GetTypeName(uint8_t type);
    const string PICC_GetTypeName(uint8_t type);
    void PICC_DumpToSerial(Uid *uid);
    void PICC_DumpMifareClassicToSerial(Uid *uid, uint8_t piccType, MIFARE_Key *key);
    void PICC_DumpMifareClassicSectorToSerial(Uid *uid, MIFARE_Key *key, uint8_t sector);
    void PICC_DumpMifareUltralightToSerial();
    void MIFARE_SetAccessBits(uint8_t *accessBitBuffer, uint8_t g0, uint8_t g1, uint8_t g2, uint8_t g3);
    bool MIFARE_OpenUidBackdoor(bool logErrors);
    bool MIFARE_SetUid(uint8_t *newUid, uint8_t uidSize, bool logErrors);
    bool MIFARE_UnbrickUidSector(bool logErrors);
 
    // Convenience functions - does not add extra functionality
    bool PICC_IsNewCardPresent();
    bool PICC_ReadCardSerial();
 
private:
    uint8_t MIFARE_TwoStepHelper(uint8_t command, uint8_t blockAddr, long data);
};
 
}