//
//    FILE: FRAM.cpp
//  AUTHOR: Rob Tillaart
// VERSION: 0.3.1
//    DATE: 2018-01-24
// PURPOSE: Arduino library for I2C FRAM
//     URL: https://github.com/RobTillaart/FRAM_I2C
//
//  HISTORY:
//  0.1.0   2018-01-24  initial version
//  0.1.1   2019-07-31  added suppport for Fujitsu 64Kbit MB85RC64T (kudos ysoyipek)
//  0.2.0   2020-04-30  refactor, add writeProtectPin code
//  0.2.1   2020-06-10  fix library.json
//  0.2.2   2020-12-23  arduino-CI + unit test + getWriteProtect()
//  0.2.3   2021-01-ii  fix getMetaData (kudos to PraxisSoft
//  0.3.0   2021-01-13  fix #2 ESP32 + WireN support
//  0.3.1   2021-02-05  fix #7 typo in .cpp


#include "FRAM.h"


const uint8_t FRAM_SLAVE_ID_= 0x7C;

/////////////////////////////////////////////////////
//
// PUBLIC
//
FRAM::FRAM(TwoWire *wire)
{
  _wire            = wire;
  _address         = 0x50;
  _writeProtectPin = -1;
}


#if defined (ESP8266) || defined(ESP32)
int FRAM::begin(uint8_t sda, uint8_t scl, const uint8_t address, int8_t writeProtectPin)
{
  if (address < 0x50 || address > 0x57) return FRAM_ERROR_ADDR;

  _wire = &Wire;
  _address = address;
  if ((sda < 255) && (scl < 255))
  {
    _wire->begin(sda, scl);
  } else {
    _wire->begin();
  }

  if (writeProtectPin > -1)
  {
    _writeProtectPin = writeProtectPin;
    pinMode(_writeProtectPin, OUTPUT);
  }
  if (! isConnected()) return FRAM_ERROR_CONNECT;
  return FRAM_OK;
}
#endif


int FRAM::begin(uint8_t address, int8_t writeProtectPin)
{
  if (address < 0x50 || address > 0x57) return FRAM_ERROR_ADDR;

  _address = address;
  _wire->begin();

  if (writeProtectPin > -1)
  {
    _writeProtectPin = writeProtectPin;
    pinMode(_writeProtectPin, OUTPUT);
  }
  if (! isConnected()) return FRAM_ERROR_CONNECT;
  return FRAM_OK;
}


bool FRAM::isConnected()
{
  _wire->beginTransmission(_address);
  return (_wire->endTransmission() == 0);
}


void FRAM::write8(uint16_t memaddr, uint8_t value)
{
  uint8_t val = value;
  writeBlock(memaddr, (uint8_t *)&val, 1);
}


void FRAM::write16(uint16_t memaddr, uint16_t value)
{
  uint16_t val = value;
  writeBlock(memaddr, (uint8_t *)&val, 2);
}


void FRAM::write32(uint16_t memaddr, uint32_t value)
{
  uint32_t val = value;
  writeBlock(memaddr, (uint8_t *)&val, 4);
}


void FRAM::write(uint16_t memaddr, uint8_t * obj, uint16_t size)
{
  const int blocksize = 24;
  uint8_t * p = obj;
  while (size >= blocksize)
  {
    writeBlock(memaddr, p, blocksize);
    memaddr += blocksize;
    p += blocksize;
    size -= blocksize;
  }
  // remaining
  if (size > 0)
  {
    writeBlock(memaddr, p, size);
  }
}


uint8_t FRAM::read8(uint16_t memaddr)
{
  uint8_t val;
  readBlock(memaddr, (uint8_t *)&val, 1);
  return val;
}


uint16_t FRAM::read16(uint16_t memaddr)
{
  uint16_t val;
  readBlock(memaddr, (uint8_t *)&val, 2);
  return val;
}


uint32_t FRAM::read32(uint16_t memaddr)
{
  uint32_t val;
  readBlock(memaddr, (uint8_t *)&val, 4);
  return val;
}


void FRAM::read(uint16_t memaddr, uint8_t * obj, uint16_t size)
{
  const uint8_t blocksize = 24;
  uint8_t * p = obj;
  while (size >= blocksize)
  {
    readBlock(memaddr, p, blocksize);
    memaddr += blocksize;
    p += blocksize;
    size -= blocksize;
  }
  // remainder
  if (size > 0)
  {
    readBlock(memaddr, p, size);
  }
}


bool FRAM::setWriteProtect(bool b)
{
  if (_writeProtectPin < 0) return false;
  digitalWrite(_writeProtectPin, b ? HIGH : LOW);
  return true;
}


bool FRAM::getWriteProtect()
{
  if (_writeProtectPin < 0) return false;
  return (digitalRead(_writeProtectPin) == HIGH);
}


uint16_t FRAM::getManufacturerID()
{
  return getMetaData(0);
}


uint16_t FRAM::getProductID()
{
  return getMetaData(1);
}


uint16_t FRAM::getSize()
{
  uint16_t val = getMetaData(2);  // density bits
  if (val > 0) return 1UL << val;
  return 0;
}

///////////////////////////////////////////////////////////
//
// PRIVATE
//

// metadata is packed as  [....MMMM][MMMMDDDD][PPPPPPPP]
// M = manufacturerID
// D = density => memsize = 2^D KB
// P = product ID (together with D)
uint16_t FRAM::getMetaData(uint8_t field)
{
  if (field > 2) return 0;

  _wire->beginTransmission(FRAM_SLAVE_ID_);
  _wire->write(_address << 1);
  _wire->endTransmission(false);
  int x = _wire->requestFrom(FRAM_SLAVE_ID_, (uint8_t)3);
  if (x != 3) return -1;

  uint32_t value = 0;
  value = _wire->read();
  value = value << 8;
  value |= _wire->read();
  value = value << 8;
  value |= _wire->read();

  // MANUFACTURER
  if (field == 0) return (value >> 12) & 0xFF;
  // PRODUCT ID
  if (field == 1) return value & 0x0FFF;
  // DENSITY
  if (field == 2) return (value >> 8) & 0x0F;
  return 0;
}


void FRAM::writeBlock(uint16_t memaddr, uint8_t * obj, uint8_t size)
{
  // TODO constrain size < 30 ??
  _wire->beginTransmission(_address);
  _wire->write(memaddr >> 8);
  _wire->write(memaddr & 0xFF);
  uint8_t * p = obj;
  for (uint8_t i = 0; i < size; i++)
  {
    _wire->write(*p++);
  }
  _wire->endTransmission();
}


void FRAM::readBlock(uint16_t memaddr, uint8_t * obj, uint8_t size)
{
  _wire->beginTransmission(_address);
  _wire->write(memaddr >> 8);
  _wire->write(memaddr & 0xFF);
  _wire->endTransmission();
  _wire->requestFrom(_address, size);
  uint8_t * p = obj;
  for (uint8_t i = 0; i < size; i++)
  {
    *p++ = _wire->read();
  }
}

// -- END OF FILE --