FMDownsampleRB.h

/*
 *   Copyright (C) 2020 by Jonathan Naylor G4KLX
 *
 *   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 2 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, write to the Free Software
 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#if !defined(FMDOWNSAMPLERB_H)
#define  FMDOWNSAMPLERB_H

#if defined(STM32F4XX)
#include "stm32f4xx.h"
#elif defined(STM32F7XX)
#include "stm32f7xx.h"
#elif defined(STM32F105xC)
#include "stm32f1xx.h"
#include <cstddef>
#else
#include <Arduino.h>
#endif

#if defined(__SAM3X8E__) || defined(STM32F105xC)
#define  ARM_MATH_CM3
#elif defined(STM32F7XX)
#define  ARM_MATH_CM7
#elif defined(STM32F4XX) || defined(__MK20DX256__) || defined(__MK64FX512__) || defined(__MK66FX1M0__)
#define  ARM_MATH_CM4
#else
#error "Unknown processor type"
#endif

#include <arm_math.h>

class CFMDownsampleRB {
public:
  CFMDownsampleRB(uint16_t length);
  
  uint16_t getSpace() const;
  
  uint16_t getData() const;

  bool put(uint8_t sample);

  bool get(uint8_t& sample);

  bool hasOverflowed();

private:
  uint16_t          m_length;
  volatile uint8_t* m_samples;
  volatile uint16_t m_head;
  volatile uint16_t m_tail;
  volatile bool     m_full;
  bool              m_overflow;
};

#endif