<?php

/*
 * Copyright (C) 2014, NoccyLabs
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>
 */

namespace NoccyLabs\Gpio\Bus;

interface BusInterface
{
    /**
     * Write data to the bus. The data will be written immediately.
     *
     */
    public function write($data);
    
    /**
     * Read data from the buffer, or perform additional null reads over the 
     * (SPI) bus to acquire the data.
     *
     */
    public function read($bytes);
    
    /**
     * Return the number of bytes in the read buffer
     *
     */
    public function getBufferFill();
}