David David - 4 months ago 19
C# Question

RFID RC522 Raspberry PI 2 Windows IOT

I'm looking for a way to use the RFID "RC522" on a Raspberry Pi 2.0 on Windows IOT.

It is of course not offical compatible...

The offical one (OM5577 demo board) is way to expensive in France (i haven't found any reseller who sold it without a lot of shipping cost (total cost is around 80$)).

The RC522 is cheap (<10$). It works great on Arduino and on Raspberry Pi 2.0 on linux. But unfortunatly not yet on Windows IOT.

I'm actually using an arduino as a bridge... It isn't an optimal solution; but work well and cost always half the price than the OM5577.

I've found this project and try to convert them into a VS (Visual C++) project with the Windows IOT SIP and IO... I miserably fail...

In my dream I would be able to use this device in C# with the standard windows IOT "ProximityDevice" class.

Have you any idea for me?

Thanks in advance.

Answer

I finally found a solution.

I haven't success in the arudino portability; so i've used this project as start point.

The project is writen in C#. I've just adapt the code for Windows IOT GPIO and SPI. An it's working !

Main

        var mfrc = new Mfrc522();
        await mfrc.InitIO();

        while (true)
        {
            if (mfrc.IsTagPresent())
            {
                var uid = mfrc.ReadUid();

                mfrc.HaltTag();
            }

        }

Library Mfrc522Lib.cs (all in one)

using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;
using Windows.Devices.Enumeration;
using Windows.Devices.Gpio;
using Windows.Devices.Spi;

namespace Mfrc522Lib
{
    public static class Registers
    {
        private const byte bitFraming = 0x0D;
        private const byte comIrq = 0x04;
        private const byte comIrqEnable = 0x02;
        private const byte command = 0x01;
        private const byte control = 0x0C;
        private const byte error = 0x06;
        private const byte fifoData = 0x09;
        private const byte fifoLevel = 0x0A;
        private const byte mode = 0x11;
        private const byte rxMode = 0x13;
        private const byte timerMode = 0x2A;
        private const byte timerPrescaler = 0x2B;
        private const byte timerReloadHigh = 0x2C;
        private const byte timerReloadLow = 0x2D;
        private const byte txAsk = 0x15;
        private const byte txControl = 0x14;
        private const byte txMode = 0x12;
        private const byte version = 0x37;

        public static byte BitFraming
        {
            get
            {
                return bitFraming;
            }
        }

        public static byte ComIrq
        {
            get
            {
                return comIrq;
            }
        }

        public static byte ComIrqEnable
        {
            get
            {
                return comIrqEnable;
            }
        }

        public static byte Command
        {
            get
            {
                return command;
            }
        }

        public static byte Control
        {
            get
            {
                return control;
            }
        }

        public static byte Error
        {
            get
            {
                return error;
            }
        }

        public static byte FifoData
        {
            get
            {
                return fifoData;
            }
        }

        public static byte FifoLevel
        {
            get
            {
                return fifoLevel;
            }
        }

        public static byte Mode
        {
            get
            {
                return mode;
            }
        }

        public static byte RxMode
        {
            get
            {
                return rxMode;
            }
        }

        public static byte TimerMode
        {
            get
            {
                return timerMode;
            }
        }

        public static byte TimerPrescaler
        {
            get
            {
                return timerPrescaler;
            }
        }

        public static byte TimerReloadHigh
        {
            get
            {
                return timerReloadHigh;
            }
        }

        public static byte TimerReloadLow
        {
            get
            {
                return timerReloadLow;
            }
        }

        public static byte TxAsk
        {
            get
            {
                return txAsk;
            }
        }

        public static byte TxControl
        {
            get
            {
                return txControl;
            }
        }

        public static byte TxMode
        {
            get
            {
                return txMode;
            }
        }

        public static byte Version
        {
            get
            {
                return version;
            }
        }
    }
    public static class PiccResponses
    {
        private const ushort answerToRequest = 0x0004;
        private const byte selectAcknowledge = 0x08;
        private const byte acknowledge = 0x0A;

        public static byte Acknowledge
        {
            get
            {
                return acknowledge;
            }
        }

        public static byte SelectAcknowledge
        {
            get
            {
                return selectAcknowledge;
            }
        }

        public static ushort AnswerToRequest
        {
            get
            {
                return answerToRequest;
            }
        }
    }
    public static class PiccCommands
    {
        private const byte anticollision_1 = 0x93;
        private const byte anticollision_2 = 0x20;
        private const byte authenticateKeyA = 0x60;
        private const byte authenticateKeyB = 0x61;
        private const byte halt_1 = 0x50;
        private const byte halt_2 = 0x00;
        private const byte read = 0x30;
        private const byte request = 0x26;
        private const byte select_1 = 0x93;
        private const byte select_2 = 0x70;
        private const byte write = 0xA0;

        public static byte AuthenticateKeyA
        {
            get
            {
                return authenticateKeyA;
            }
        }

        public static byte AuthenticateKeyB
        {
            get
            {
                return authenticateKeyB;
            }
        }

        public static byte Halt_1
        {
            get
            {
                return halt_1;
            }
        }

        public static byte Halt_2
        {
            get
            {
                return halt_2;
            }
        }

        public static byte Read
        {
            get
            {
                return read;
            }
        }

        public static byte Request
        {
            get
            {
                return request;
            }
        }

        public static byte Select_1
        {
            get
            {
                return select_1;
            }
        }

        public static byte Select_2
        {
            get
            {
                return select_2;
            }
        }

        public static byte Write
        {
            get
            {
                return write;
            }
        }

        public static byte Anticollision_1
        {
            get
            {
                return anticollision_1;
            }
        }

        public static byte Anticollision_2
        {
            get
            {
                return anticollision_2;
            }
        }
    }

    public static class PcdCommands
    {
        private const byte idle = 0x00;
        private const byte mifareAuthenticate = 0x0E;
        private const byte transceive = 0x0C;

        public static byte Idle
        {
            get
            {
                return idle;
            }
        }

        public static byte MifareAuthenticate
        {
            get
            {
                return mifareAuthenticate;
            }
        }

        public static byte Transceive
        {
            get
            {
                return transceive;
            }
        }
    }


    public class Uid
    {
        public byte Bcc { get; private set; }
        public byte[] Bytes { get; private set; }
        public byte[] FullUid { get; private set; }
        public bool IsValid { get; private set; }

        internal Uid(byte[] uid)
        {
            FullUid = uid;
            Bcc = uid[4];

            Bytes = new byte[4];
            System.Array.Copy(FullUid, 0, Bytes, 0, 4);

            foreach (var b in Bytes)
            {
                if (b != 0x00)
                    IsValid = true;
            }
        }

        public sealed override bool Equals(object obj)
        {
            if (!(obj is Uid))
                return false;

            var uidWrapper = (Uid)obj;

            for (int i = 0; i < 5; i++)
            {
                if (FullUid[i] != uidWrapper.FullUid[i])
                    return false;
            }

            return true;
        }

        public sealed override int GetHashCode()
        {
            int uid = 0;

            for (int i = 0; i < 4; i++)
                uid |= Bytes[i] << (i * 8);

            return uid;
        }

        public sealed override string ToString()
        {
            var formatString = "x" + (Bytes.Length * 2);
            return GetHashCode().ToString(formatString);
        }
    }

    public sealed class Mfrc522
    {
        public SpiDevice _spi { get; private set; }
        public GpioController IoController { get; private set; }
        public GpioPin _resetPowerDown { get; private set; }

        /* Uncomment for Raspberry Pi 2 */
        private const string SPI_CONTROLLER_NAME = "SPI0"; 
        private const Int32 SPI_CHIP_SELECT_LINE = 0;  
        private const Int32 RESET_PIN = 25;

        internal async Task InitIO()
        {

            try
            {
                IoController = GpioController.GetDefault(); 

                _resetPowerDown = IoController.OpenPin(RESET_PIN);
                _resetPowerDown.Write(GpioPinValue.High);
                _resetPowerDown.SetDriveMode(GpioPinDriveMode.Output);
            }
            /* If initialization fails, throw an exception */
            catch (Exception ex)
            {
                throw new Exception("GPIO initialization failed", ex);
            }

            try
            {
                var settings = new SpiConnectionSettings(SPI_CHIP_SELECT_LINE);
                settings.ClockFrequency = 1000000;
                settings.Mode = SpiMode.Mode0;

                String spiDeviceSelector = SpiDevice.GetDeviceSelector();
                IReadOnlyList<DeviceInformation> devices = await DeviceInformation.FindAllAsync(spiDeviceSelector);

                _spi = await SpiDevice.FromIdAsync(devices[0].Id, settings); 

            }
            /* If initialization fails, display the exception and stop running */
            catch (Exception ex)
            {
                throw new Exception("SPI Initialization Failed", ex);
            }


            Reset();
        }

        public void Reset()
        {
            _resetPowerDown.Write(GpioPinValue.Low);
            System.Threading.Tasks.Task.Delay(50).Wait();
            _resetPowerDown.Write(GpioPinValue.High);
            System.Threading.Tasks.Task.Delay(50).Wait();

            // Force 100% ASK modulation
            WriteRegister(Registers.TxAsk, 0x40);

            // Set CRC to 0x6363
            WriteRegister(Registers.Mode, 0x3D);

            // Enable antenna
            SetRegisterBits(Registers.TxControl, 0x03);
        }


        public bool IsTagPresent()
        {
            // Enable short frames
            WriteRegister(Registers.BitFraming, 0x07);

            // Transceive the Request command to the tag
            Transceive(false, PiccCommands.Request);

            // Disable short frames
            WriteRegister(Registers.BitFraming, 0x00);

            // Check if we found a card
            return GetFifoLevel() == 2 && ReadFromFifoShort() == PiccResponses.AnswerToRequest;
        }

        public Uid ReadUid()
        {
            // Run the anti-collision loop on the card
            Transceive(false, PiccCommands.Anticollision_1, PiccCommands.Anticollision_2);

            // Return tag UID from FIFO
            return new Uid(ReadFromFifo(5));
        }

        public void HaltTag()
        {
            // Transceive the Halt command to the tag
            Transceive(false, PiccCommands.Halt_1, PiccCommands.Halt_2);
        }

        public bool SelectTag(Uid uid)
        {
            // Send Select command to tag
            var data = new byte[7];
            data[0] = PiccCommands.Select_1;
            data[1] = PiccCommands.Select_2;
            uid.FullUid.CopyTo(data, 2);

            Transceive(true, data);

            return GetFifoLevel() == 1 && ReadFromFifo() == PiccResponses.SelectAcknowledge;
        }

        internal byte[] ReadBlock(byte blockNumber, Uid uid, byte[] keyA = null, byte[] keyB = null)
        {
            if (keyA != null)
                MifareAuthenticate(PiccCommands.AuthenticateKeyA, blockNumber, uid, keyA);
            else if (keyB != null)
                MifareAuthenticate(PiccCommands.AuthenticateKeyB, blockNumber, uid, keyB);
            else
                return null;

            // Read block
            Transceive(true, PiccCommands.Read, blockNumber);

            return ReadFromFifo(16);
        }

        internal bool WriteBlock(byte blockNumber, Uid uid, byte[] data, byte[] keyA = null, byte[] keyB = null)
        {
            if (keyA != null)
                MifareAuthenticate(PiccCommands.AuthenticateKeyA, blockNumber, uid, keyA);
            else if (keyB != null)
                MifareAuthenticate(PiccCommands.AuthenticateKeyB, blockNumber, uid, keyB);
            else
                return false;

            // Write block
            Transceive(true, PiccCommands.Write, blockNumber);

            if (ReadFromFifo() != PiccResponses.Acknowledge)
                return false;

            // Make sure we write only 16 bytes
            var buffer = new byte[16];
            data.CopyTo(buffer, 0);

            Transceive(true, buffer);

            return ReadFromFifo() == PiccResponses.Acknowledge;
        }


        protected void MifareAuthenticate(byte command, byte blockNumber, Uid uid, byte[] key)
        {
            // Put reader in Idle mode
            WriteRegister(Registers.Command, PcdCommands.Idle);

            // Clear the FIFO
            SetRegisterBits(Registers.FifoLevel, 0x80);

            // Create Authentication packet
            var data = new byte[12];
            data[0] = command;
            data[1] = (byte)(blockNumber & 0xFF);
            key.CopyTo(data, 2);
            uid.Bytes.CopyTo(data, 8);

            WriteToFifo(data);

            // Put reader in MfAuthent mode
            WriteRegister(Registers.Command, PcdCommands.MifareAuthenticate);

            // Wait for (a generous) 25 ms
            System.Threading.Tasks.Task.Delay(25).Wait();
        }

        protected void Transceive(bool enableCrc, params byte[] data)
        {
            if (enableCrc)
            {
                // Enable CRC
                SetRegisterBits(Registers.TxMode, 0x80);
                SetRegisterBits(Registers.RxMode, 0x80);
            }

            // Put reader in Idle mode
            WriteRegister(Registers.Command, PcdCommands.Idle);

            // Clear the FIFO
            SetRegisterBits(Registers.FifoLevel, 0x80);

            // Write the data to the FIFO
            WriteToFifo(data);

            // Put reader in Transceive mode and start sending
            WriteRegister(Registers.Command, PcdCommands.Transceive);
            SetRegisterBits(Registers.BitFraming, 0x80);

            // Wait for (a generous) 25 ms
            System.Threading.Tasks.Task.Delay(25).Wait();

            // Stop sending
            ClearRegisterBits(Registers.BitFraming, 0x80);

            if (enableCrc)
            {
                // Disable CRC
                ClearRegisterBits(Registers.TxMode, 0x80);
                ClearRegisterBits(Registers.RxMode, 0x80);
            }
        }


        protected byte[] ReadFromFifo(int length)
        {
            var buffer = new byte[length];

            for (int i = 0; i < length; i++)
                buffer[i] = ReadRegister(Registers.FifoData);

            return buffer;
        }

        protected byte ReadFromFifo()
        {
            return ReadFromFifo(1)[0];
        }

        protected void WriteToFifo(params byte[] values)
        {
            foreach (var b in values)
                WriteRegister(Registers.FifoData, b);
        }

        protected int GetFifoLevel()
        {
            return ReadRegister(Registers.FifoLevel);
        }


        protected byte ReadRegister(byte register)
        {
            register <<= 1;
            register |= 0x80;

            var writeBuffer = new byte[] { register, 0x00 };

            return TransferSpi(writeBuffer)[1];
        }

        protected ushort ReadFromFifoShort()
        {
            var low = ReadRegister(Registers.FifoData);
            var high = (ushort)(ReadRegister(Registers.FifoData) << 8);

            return (ushort)(high | low);
        }

        protected void WriteRegister(byte register, byte value)
        {
            register <<= 1;

            var writeBuffer = new byte[] { register, value };

            TransferSpi(writeBuffer);
        }

        protected void SetRegisterBits(byte register, byte bits)
        {
            var currentValue = ReadRegister(register);
            WriteRegister(register, (byte)(currentValue | bits));
        }

        protected void ClearRegisterBits(byte register, byte bits)
        {
            var currentValue = ReadRegister(register);
            WriteRegister(register, (byte)(currentValue & ~bits));
        }


        private byte[] TransferSpi(byte[] writeBuffer)
        {
            var readBuffer = new byte[writeBuffer.Length];

            _spi.TransferFullDuplex(writeBuffer, readBuffer);

            return readBuffer;
        }
    }
}

Schema

Schema