arduino的IIC.h库文件

以下是Arduino的Wire.h库文件的示例代码：

#ifndef TwoWire_h
#define TwoWire_h

#include <inttypes.h>

#define BUFFER_LENGTH 32

class TwoWire {
  private:
    static uint8_t rxBuffer[];
    static uint8_t rxBufferIndex;
    static uint8_t rxBufferLength;

    static uint8_t txAddress;
    static uint8_t txBuffer[];
    static uint8_t txBufferIndex;
    static uint8_t txBufferLength;

    static uint8_t transmitting;
    static void (*user_onRequest)(void);
    static void (*user_onReceive)(int);

  public:
    TwoWire();
    void begin();
    void begin(uint8_t);
    void begin(int);
    void beginTransmission(uint8_t);
    uint8_t endTransmission(void);
    uint8_t requestFrom(uint8_t, uint8_t);
    uint8_t requestFrom(int, int);
    virtual size_t write(uint8_t);
    virtual size_t write(const uint8_t *, size_t);
    virtual int available(void);
    virtual int read(void);
    virtual int peek(void);
    virtual void flush(void);
    void onReceive( void (*)(int) );
    void onRequest( void (*)(void) );
};

extern TwoWire Wire;

#endif

该库文件定义了TwoWire类，该类包含了许多I2C通讯所需的函数，例如beginTransmission()，requestFrom()和write()等函数。在使用I2C通讯时，您可以使用Wire对象调用这些函数。