communication.h

 
#ifndef COMM_INTERFACE_H
#define COMM_INTERFACE_H
 
#ifdef __cplusplus
extern "C" 
{
    #include <avr/interrupt.h>
}
#endif
 
#include "defs.h"
#include "protocol.h"
 
#ifdef DEBUG
#include "logger.h"
#endif
 
enum class PinDir
{
    OUTPUT  = 0,    
    INPUT   = 1     
};
 
class Communication
{
public:
    // ******************************************************************************
    // Public Methods ***************************************************************
    // ******************************************************************************
    Communication();
    
    void sendATR() { sendBytes(Protocol::ATR_SEQ, Protocol::ATR_LENGTH); }
 
    void receiveDataToDecrypt(byte_t *data);
    
    void sendDecryptedData(const byte_t *data);
 
private:
    // ******************************************************************************
    // Private Subclasses ***********************************************************
    // ******************************************************************************
    class Timer
    {
    public:
        // Public Methods ***********************************************************
        static void init(Communication *comm);
        
        static void stop() { CLR_BIT(TCCR1B, CS10); }
 
        static void start() { TCNT1 = TIMER_BOTTOM; SET_BIT(TCCR1B, CS10); }
 
        static void setMatchValue(const uint16_t matchValue) { OCR1A = matchValue; }
        
        static constexpr uint16_t ETU = 372/1;
 
    private:
        // Private Attributes *******************************************************
        static Communication *mComm;                            
        static constexpr uint16_t TIMER_BOTTOM = 0x0000;        
 
        // Private Methods **********************************************************
        static void serviceRoutine() __asm__("__vector_13") __attribute__((__signal__, __used__, __externally_visible__));
    };
 
    class IOPin
    {
    public:
        // Public Methods ***********************************************************
        static void init(Communication *comm);
        
        static void setLevel(const bit_t bit);
 
        static void setDirection(const PinDir direction);
 
        static void setInterrupt(const bool enabled);
    
    private:
        // Private Attributes *******************************************************
        static Communication *mComm; 
 
        // Private Methods **********************************************************
        static void serviceRoutine() __asm__("__vector_5") __attribute__((__signal__, __used__, __externally_visible__));
    };
 
    // ******************************************************************************
    // Private Attributes ***********************************************************
    // ******************************************************************************
    // Static Constexpr Attributes **************************************************
    static constexpr bit_t START_BIT        = 0;                
    static constexpr bit_t STOP_BIT         = 1;                
 
    // Class Objects ****************************************************************
    friend Timer;   
    friend IOPin;   
    #ifdef DEBUG
    Logger mLog;    
    #endif
 
    // Volatile Attributes **********************************************************
    volatile PinDir     mDirection          = PinDir::OUTPUT;   
    // Output flags/data
    volatile bool       mBitSent            = true;             
    volatile bit_t      mOutputBit          = 0;                
    // Input flags/data
    volatile bool       mByteReceived       = 0;                
    volatile uint8_t    mInputBitCounter    = 0;                
    volatile byte_t     mInputByte          = 0x00;             
    // Error flags/data
    volatile bool       mCheckErrors        = false;            
    volatile bit_t      mErrorBit           = 0;                
    volatile bool       mParityError        = false;            
 
    // ******************************************************************************
    // Private Methods **************************************************************
    // ******************************************************************************
    // Send/Receive *****************************************************************
    void sendBit(const bit_t bit);
 
    void sendByte(const byte_t byte);
 
    void sendBytes(const byte_t *bytes, const uint8_t len) { for(uint8_t i=0; i<len; i++) sendByte(bytes[i]); }
 
    static bit_t sampleBit();
 
    byte_t receiveByte();
 
    void receiveProtocolHeader(const byte_t *header);
 
    // Helper functions *************************************************************
    static bit_t getParity(byte_t byte);
};
 
#endif // COMM_INTERFACE_H