Wire.h

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/*
  TwoWire.h - TWI/I2C library for Arduino & Wiring
  Copyright (c) 2006 Nicholas Zambetti.  All right reserved.

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.

  This library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

  Modified 2012 by Todd Krein (todd@krein.org) to implement repeated starts
  Modified December 2014 by Ivan Grokhotkov (ivan@esp8266.com) - esp8266 support
  Modified April 2015 by Hrsto Gochkov (ficeto@ficeto.com) - alternative esp8266 support
*/

#pragma once

#include <inttypes.h>
#include "Stream.h"

#define BUFFER_LENGTH 32

class TwoWire : public Stream
{
public:
    TwoWire();

    void begin(int sda, int scl);
    void pins(int sda, int scl);
    void begin();
    void begin(uint8_t);
    void begin(int);
    void setClock(uint32_t);
    void setClockStretchLimit(uint32_t);
    void beginTransmission(uint8_t);
    void beginTransmission(int);
    uint8_t endTransmission();
    uint8_t endTransmission(uint8_t);
    size_t requestFrom(uint8_t address, size_t size, bool sendStop);
    uint8_t status();

    uint8_t requestFrom(uint8_t, uint8_t);
    uint8_t requestFrom(uint8_t, uint8_t, uint8_t);
    uint8_t requestFrom(int, int);
    uint8_t requestFrom(int, int, int);

    size_t write(uint8_t) override;
    size_t write(const uint8_t*, size_t) override;
    int available() override;
    int read() override;
    int peek() override;
    void flush() override;

    void onReceive(void (*)(int));
    void onRequest(void (*)());

    size_t write(unsigned long n)
    {
        return write(uint8_t(n));
    }

    size_t write(long n)
    {
        return write(uint8_t(n));
    }

    size_t write(unsigned int n)
    {
        return write(uint8_t(n));
    }

    size_t write(int n)
    {
        return write(uint8_t(n));
    }

    using Print::write;

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)();
    static void (*user_onReceive)(int);
    static void onRequestService();
    static void onReceiveService(uint8_t*, int);
};

#if !defined(NO_GLOBAL_INSTANCES) && !defined(NO_GLOBAL_TWOWIRE)
extern TwoWire Wire;
#endif