File content as of revision 3:925096a4c7f0:

/***********************************************************
Author: Bernard Borredon
Version: 1.3
  - Correct write(uint32_t address, int8_t data[], uint32_t length) for eeprom >= T24C32.
    Tested with 24C02, 24C08, 24C16, 24C64, 24C256, 24C512, 24C1025 on LPC1768 (mbed online and µVision V5.16a).
  - Correct main test.
    
Date : 12 decembre 2013
Version: 1.2
  - Update api documentation
  
Date: 11 december 2013
Version: 1.1
  - Change address parameter size form uint16_t to uint32_t (error for eeprom > 24C256).
  - Change size parameter size from uint16_t to uint32_t (error for eeprom > 24C256).
    - Correct a bug in function write(uint32_t address, int8_t data[], uint32_t length) :
      last step must be done only if it remain datas to send.
    - Add function getName.
    - Add function clear.
    - Initialize _name array.

Date: 27 december 2011
Version: 1.0

************************************************************/
#include "eeprom.h"

#define BIT_SET(x,n) (x=x | (0x01<<n))
#define BIT_TEST(x,n) (x & (0x01<<n))
#define BIT_CLEAR(x,n) (x=x & ~(0x01<<n))

const char * const EEPROM::_name[] = {"24C01","24C02","24C04","24C08","24C16","24C32",
                                        "24C64","24C128","24C256","24C512","24C1024","24C1025"};

/**
 * EEPROM(PinName sda, PinName scl, uint8_t address, TypeEeprom type) : _i2c(sda, scl)
 *
 * Constructor, initialize the eeprom on i2c interface.
 * @param sda sda i2c pin (PinName)
 * @param scl scl i2c pin (PinName)
 * @param address eeprom address, according to eeprom type (uint8_t)
 * @param type eeprom type (TypeEeprom) 
 * @return none
*/
EEPROM::EEPROM(PinName sda, PinName scl, uint8_t address, TypeEeprom type) : _i2c(sda, scl) 
{
  
  _errnum = EEPROM_NoError;
  _type = type;
  
  // Check address range
  _address = address;
  switch(type) {
                 case T24C01 :
                 case T24C02 :
                    if(address > 7) {
                      _errnum = EEPROM_BadAddress;
                    }
                    _address = _address << 1;
                    _page_write = 8;
                    _page_number = 1;
                    break;
                 case T24C04 :
                    if(address > 7) {
                      _errnum = EEPROM_BadAddress;
                    }
                    _address = (_address & 0xFE) << 1;
                    _page_write = 16;
                    _page_number = 2;
                    break;
                 case T24C08 :
                    if(address > 7) {
                      _errnum = EEPROM_BadAddress;
                    }
                    _address = (_address & 0xFC) << 1;
                    _page_write = 16;
                    _page_number = 4;
                    break;
                 case T24C16 :
                    _address = 0;
                    _page_write = 16;
                    _page_number = 8;
                    break;
                  case T24C32 :
                  case T24C64 :
                    if(address > 7) {
                      _errnum = EEPROM_BadAddress;
                    }
                    _address = _address << 1;
                    _page_write = 32;
                    _page_number = 1;
                    break;
                  case T24C128 :
                  case T24C256 :
                    if(address > 3) {
                      _errnum = EEPROM_BadAddress;
                    }
                    _address = _address << 1;
                    _page_write = 64;
                    _page_number = 1;
                    break;
                 case T24C512 :
                    if(address > 3) {
                      _errnum = EEPROM_BadAddress;
                    }
                    _address = _address << 1;
                    _page_write = 128;
                    _page_number = 1;
                    break;
                 case T24C1024 :
                    if(address > 7) {
                      _errnum = EEPROM_BadAddress;
                    }
                    _address = (_address & 0xFE) << 1;
                    _page_write = 128;
                    _page_number = 2;
                    break;
                 case T24C1025 :
                    if(address > 3) {
                      _errnum = EEPROM_BadAddress;
                    }
                    _address = _address << 1;
                    _page_write = 128;
                    _page_number = 2;
                    break;
  }
  
  // Size in bytes
  _size = _type;
  if(_type == T24C1025)
    _size = T24C1024;
  
  // Set I2C frequency
  _i2c.frequency(400000);

}

/**
 * void write(uint32_t address, int8_t data)
 *
 * Write byte
 * @param address start address (uint32_t)
 * @param data byte to write (int8_t)
 * @return none
*/
void EEPROM::write(uint32_t address, int8_t data)
{
  uint8_t page;
  uint8_t addr;
  uint8_t cmd[3];
  int len;
  int ack;
    
  // Check error
  if(_errnum) 
    return;
    
  // Check address
  if(!checkAddress(address)) {
    _errnum = EEPROM_OutOfRange;
    return;
  }
  
  // Compute page number
  page = 0;
  if(_type < T24C32)
    page = (uint8_t) (address / 256); 
  
  // Device address
  addr = EEPROM_Address | _address | (page << 1);
 
  if(_type < T24C32) {
    len = 2;
    
    // Word address 
    cmd[0] = (uint8_t) (address - page * 256);
  
    // Data
    cmd[1] = (uint8_t) data;
  }
  else {
    len = 3;
    
    // First word address (MSB)
    cmd[0] = (uint8_t) (address >> 8);
    
    // Second word address (LSB)
    cmd[1] = (uint8_t) address;
    
    // Data
    cmd[2] = (uint8_t) data;
  }
    
  ack = _i2c.write((int)addr,(char *)cmd,len);
  if(ack != 0) {
    _errnum = EEPROM_I2cError;
    return;
  }
  
  // Wait end of write
  ready();

}

/**
 * void write(uint32_t address, int8_t data[], uint32_t length)
 *
 * Write array of bytes (use the page mode)
 * @param address start address (uint32_t)
 * @param data bytes array to write (int8_t[])
 * @param size number of bytes to write (uint32_t)
 * @return none
*/
void EEPROM::write(uint32_t address, int8_t data[], uint32_t length)
{
  uint8_t page;
  uint8_t addr = 0;
  uint8_t blocs,remain;
  uint8_t fpart,lpart;
  uint8_t i,j,ind;
  uint8_t cmd[129];
  int ack;
    
  // Check error
  if(_errnum) 
    return;
    
  // Check address
  if(!checkAddress(address)) {
    _errnum = EEPROM_OutOfRange;
    return;
  }
  
  // Check length
  if(!checkAddress(address + length - 1)) {
    _errnum = EEPROM_OutOfRange;
    return;
  }
  
  // Compute blocs numbers
  blocs = length / _page_write;
  
  // Compute remaining bytes
  remain = length - blocs * _page_write;
    
  for(i = 0;i < blocs;i++) {
     // Compute page number
     page = 0;
     if(_type < T24C32)
       page = (uint8_t) (address / 256); 
  
     // Device address
     addr = EEPROM_Address | _address | (page << 1);
  
     if(_type < T24C32) {
       // Word address
       cmd[0] = (uint8_t) (address - page * 256);
     
       if((uint8_t) ((address + _page_write) / 256) == page) { // Data fit in the same page
         // Add data 
         for(j = 0;j < _page_write;j++)
            cmd[j + 1] = (uint8_t) data[i * _page_write + j];
    
         // Write data
         ack = _i2c.write((int)addr,(char *)cmd,_page_write + 1);
         if(ack != 0) {
           _errnum = EEPROM_I2cError;
           return;
         }
  
         // Wait end of write
         ready();
       
         // Increment address
         address += _page_write;
       }
       else { // Data on 2 pages. We must split the write
         // Number of bytes in current page
         fpart = (page + 1) * 256 - address;
       
         // Add data for current page
         for(j = 0;j < fpart;j++)
            cmd[j + 1] = (uint8_t) data[i * _page_write + j];
    
         // Write data for current page
         ack = _i2c.write((int)addr,(char *)cmd,fpart + 1);
         if(ack != 0) {
           _errnum = EEPROM_I2cError;
           return;
         }
  
         // Wait end of write
         ready();
       
         // Increment address
         address += fpart;
       
         if(page < _page_number - 1) {
           // Increment page
           page++;
       
           // Device address
           addr = EEPROM_Address | _address | (page << 1);
       
           // Word address
           cmd[0] = (uint8_t) (address - page * 256);
       
           // Data index
           ind = i * _page_write + fpart;
       
           // Number of bytes in next page
           lpart = _page_write - fpart;
       
           // Add data for next page
           for(j = 0;j < lpart;j++)
              cmd[j + 1] = (uint8_t) data[ind + j];
    
           // Write data for next page
           ack = _i2c.write((int)addr,(char *)cmd,lpart + 1);
           if(ack != 0) {
             _errnum = EEPROM_I2cError;
             return;
           }
  
           // Wait end of write
           ready();
       
           // Increment address
           address += lpart;
         }
       }
     }
     else {
       // First word address (MSB)
       cmd[0] = (uint8_t) (address >> 8);
       
       // Second word address (LSB)
       cmd[1] = (uint8_t) address;
       
       // Add data 
       for(j = 0;j < _page_write;j++)
          cmd[j + 2] = (uint8_t) data[i * _page_write + j];
    
       // Write data
       ack = _i2c.write((int)addr,(char *)cmd,_page_write + 2);
       if(ack != 0) {
         _errnum = EEPROM_I2cError;
         return;
       }
  
       // Wait end of write
       ready();
       
       // Increment address
       address += _page_write;
     }
  }
  
  if(remain) {
    // Compute page number
    page = 0;
    if(_type < T24C32)
      page = (uint8_t) (address / 256); 
  
    // Device address
    addr = EEPROM_Address | _address | (page << 1);
  
    if(_type < T24C32) {
      // Word address
      cmd[0] = (uint8_t) (address - page * 256);
  
      if((uint8_t) ((address + remain) / 256) == page) { // Data fit in the same page
        // Add data for the current page
        for(j = 0;j < remain;j++)
           cmd[j + 1] = (uint8_t) data[blocs * _page_write + j];
    
        // Write data for the current page
        ack = _i2c.write((int)addr,(char *)cmd,remain + 1);
        if(ack != 0) {
          _errnum = EEPROM_I2cError;
          return;
        }
  
        // Wait end of write
        ready();
      }
      else { // Data on 2 pages. We must split the write
        // Number of bytes in current page
        fpart = (page + 1) * 256 - address;
    
        // Add data for current page
        for(j = 0;j < fpart;j++)
           cmd[j + 1] = (uint8_t) data[blocs * _page_write + j];
    
        // Write data for current page
        ack = _i2c.write((int)addr,(char *)cmd,fpart + 1);
        if(ack != 0) {
          _errnum = EEPROM_I2cError;
          return;
        }
  
        // Wait end of write
        ready();
    
        // Increment address
        address += fpart;
       
        if(page < _page_number - 1) {
          // Increment page
          page++;
    
          // Device address
          addr = EEPROM_Address | _address | (page << 1);
    
          // Word address
          cmd[0] = (uint8_t) (address - page * 256);
    
          // Data index
          ind = blocs * _page_write + fpart;
    
          // Number of bytes in next page
          lpart = remain - fpart;
    
          // Add data for next page
          for(j = 0;j < lpart;j++)
             cmd[j + 1] = (uint8_t) data[ind + j];
    
          // Write data for next page
          ack = _i2c.write((int)addr,(char *)cmd,lpart + 1);
          if(ack != 0) {
            _errnum = EEPROM_I2cError;
            return;
          }
        
          // Wait end of write
          ready();
        }
      }
    }
    else {
      // Fist word address (MSB)
      cmd[0] = (uint8_t) (address >> 8);
    
      // Second word address (LSB)
      cmd[1] = (uint8_t) address;

      // Add data for the current page
      for(j = 0;j < remain;j++)
         cmd[j + 2] = (uint8_t) data[blocs * _page_write + j];
        
      // Write data for the current page
      ack = _i2c.write((int)addr,(char *)cmd,remain + 2);
      if(ack != 0) {
        _errnum = EEPROM_I2cError;
        return;
      }
  
      // Wait end of write
      ready();
        }
  }
  
}

/**
 * void write(uint32_t address, int16_t data)
 *
 * Write short
 * @param address start address (uint32_t)
 * @param data short to write (int16_t)
 * @return none
*/
void EEPROM::write(uint32_t address, int16_t data)
{
  int8_t cmd[2];
    
  // Check error
  if(_errnum) 
    return;
    
  // Check address
  if(!checkAddress(address + 1)) {
    _errnum = EEPROM_OutOfRange;
    return;
  }
  
  memcpy(cmd,&data,2);
  
  write(address,cmd,2);
  
}

/**
 * void write(uint32_t address, int32_t data)
 *
 * Write long
 * @param address start address (uint32_t)
 * @param data long to write (int32_t)
 * @return none
*/
void EEPROM::write(uint32_t address, int32_t data)
{
  int8_t cmd[4];
    
  // Check error
  if(_errnum) 
    return;
    
  // Check address
  if(!checkAddress(address + 3)) {
    _errnum = EEPROM_OutOfRange;
    return;
  }
  
  memcpy(cmd,&data,4);
  
  write(address,cmd,4);
  
}

/**
 * void write(uint32_t address, float data)
 *
 * Write float
 * @param address start address (uint32_t)
 * @param data float to write (float)
  * @return none
*/
void EEPROM::write(uint32_t address, float data)
{
  int8_t cmd[4];
    
  // Check error
  if(_errnum) 
    return;
    
  // Check address
  if(!checkAddress(address + 3)) {
    _errnum = EEPROM_OutOfRange;
    return;
  }
  
  memcpy(cmd,&data,4);
  
  write(address,cmd,4);
  
}

/**
 * void write(uint32_t address, void *data, uint32_t size)
 *
 * Write anything (use the page write mode)
 * @param address start address (uint32_t)
 * @param data data to write (void *)
 * @param size number of bytes to write (uint32_t)
 * @return none
*/
void EEPROM::write(uint32_t address, void *data, uint32_t size)
{
  int8_t *cmd = NULL;
    
  // Check error
  if(_errnum) 
    return;
    
  // Check address
  if(!checkAddress(address + size - 1)) {
    _errnum = EEPROM_OutOfRange;
    return;
  }
  
  cmd = (int8_t *)malloc(size);
  if(cmd == NULL) {
    _errnum = EEPROM_MallocError;
    return;
  }
    
  memcpy(cmd,(uint8_t *)data,size);
  
  write(address,cmd,size);
    
  free(cmd);
  
}

/**
 * void read(uint32_t address, int8_t& data)
 *
 * Random read byte
 * @param address start address (uint32_t)
 * @param data byte to read (int8_t&)
 * @return none
*/
void EEPROM::read(uint32_t address, int8_t& data)
{
  uint8_t page;
  uint8_t addr;
  uint8_t cmd[2];
  uint8_t len;
  int ack;
    
  // Check error
  if(_errnum) 
    return;
    
  // Check address
  if(!checkAddress(address)) {
    _errnum = EEPROM_OutOfRange;
    return;
  }
    
  // Compute page number
  page = 0;
  if(_type < T24C32)
    page = (uint8_t) (address / 256); 
  
  // Device address
  addr = EEPROM_Address | _address | (page << 1);
  
  if(_type < T24C32) {
    len = 1;
    
    // Word address
    cmd[0] = (uint8_t) (address - page * 256);
  }
  else {
    len = 2;
    
    // First word address (MSB)
    cmd[0] = (uint8_t) (address >> 8);
    
    // Second word address (LSB)
    cmd[1] = (uint8_t)address;
  }
  
  // Write command
  ack = _i2c.write((int)addr,(char *)cmd,len,true);
  if(ack != 0) {
    _errnum = EEPROM_I2cError;
    return;
  }
  
  // Read data
  ack = _i2c.read((int)addr,(char *)&data,sizeof(data));
  if(ack != 0) {
    _errnum = EEPROM_I2cError;
    return;
  }
  
}

/**
 * void read(uint32_t address, int8_t *data, uint32_t size)
 *
 * Sequential read byte
 * @param address start address (uint32_t)
 * @param data bytes array to read (int8_t[]&)
 * @param size number of bytes to read (uint32_t)
 * @return none
*/
void EEPROM::read(uint32_t address, int8_t *data, uint32_t size)
{
  uint8_t page;
  uint8_t addr;
  uint8_t cmd[2];
  uint8_t len;
  int ack;
    
  // Check error
  if(_errnum) 
    return;
    
  // Check address
  if(!checkAddress(address)) {
    _errnum = EEPROM_OutOfRange;
    return;
  }
  
  // Check size
  if(!checkAddress(address + size - 1)) {
    _errnum = EEPROM_OutOfRange; 
    return;
  }
  
  // Compute page number
  page = 0;
  if(_type < T24C32)
    page = (uint8_t) (address / 256); 
  
  // Device address
  addr = EEPROM_Address | _address | (page << 1);
  
  if(_type < T24C32) {
    len = 1;
    
    // Word address
    cmd[0] = (uint8_t) (address - page * 256);
  }
  else {
    len = 2;
    
    // First word address (MSB)
    cmd[0] = (uint8_t) (address >> 8);
    
    // Second word address (LSB)
    cmd[1] = (uint8_t) address;
  }
  
  // Write command 
  ack = _i2c.write((int)addr,(char *)cmd,len,true);
  if(ack != 0) {
    _errnum = EEPROM_I2cError;
    return;
  }
  
  // Sequential read
  ack = _i2c.read((int)addr,(char *)data,size);
  if(ack != 0) {
    _errnum = EEPROM_I2cError;
    return;
  }
  
}

/**
 * void read(int8_t& data)
 *
 * Current address read byte
 * @param data byte to read (int8_t&)
 * @return none
 */
void EEPROM::read(int8_t& data)
{
  uint8_t addr;
  int ack;
    
  // Check error
  if(_errnum) 
    return;
  
  // Device address
  addr = EEPROM_Address | _address;

  // Read data
  ack = _i2c.read((int)addr,(char *)&data,sizeof(data));
  if(ack != 0) {
    _errnum = EEPROM_I2cError;
    return;
  }
  
}

/**
 * void read(uint32_t address, int16_t& data)
 *
 * Random read short
 * @param address start address (uint32_t)
 * @param data short to read (int16_t&)
 * @return none
*/
void EEPROM::read(uint32_t address, int16_t& data)
{
  int8_t cmd[2];
        
  // Check error
  if(_errnum) 
    return;
    
  // Check address
  if(!checkAddress(address + 1)) {
    _errnum = EEPROM_OutOfRange;
    return;
  }
 
  read(address,cmd,2);
  
  memcpy(&data,cmd,2);
  
}

/**
 * void read(uint32_t address, int32_t& data)
 *
 * Random read long
 * @param address start address (uint32_t)
 * @param data long to read (int32_t&)
 * @return none
*/
void EEPROM::read(uint32_t address, int32_t& data)
{
  int8_t cmd[4];
    
  // Check error
  if(_errnum) 
    return;
    
  // Check address
  if(!checkAddress(address + 3)) {
    _errnum = EEPROM_OutOfRange;
    return;
  }
 
  read(address,cmd,4);
  
  memcpy(&data,cmd,4);
  
}

/**
 * void read(uint32_t address, float& data)
 *
 * Random read float
 * @param address start address (uint32_t)
 * @param data float to read (float&)
 * @return none
 */
void EEPROM::read(uint32_t address, float& data)
{
  int8_t cmd[4];
    
  // Check error
  if(_errnum) 
    return;
    
  // Check address
  if(!checkAddress(address + 3)) {
    _errnum = EEPROM_OutOfRange;
    return;
  }
  
  read(address,cmd,4);
  
  memcpy(&data,cmd,4);
  
}

/**
 * void read(uint32_t address, void *data, uint32_t size)
 *
 * Random read anything
 * @param address start address (uint32_t)
 * @param data data to read (void *)
 * @param size number of bytes to read (uint32_t)
 * @return none
*/
void EEPROM::read(uint32_t address, void *data, uint32_t size)
{
  int8_t *cmd = NULL;
    
  // Check error
  if(_errnum) 
    return;
    
  // Check address
  if(!checkAddress(address + size - 1)) {
    _errnum = EEPROM_OutOfRange;
    return;
  }
  
  cmd = (int8_t *)malloc(size);

  if(cmd == NULL) {
    _errnum = EEPROM_MallocError;
    return;
  }
  
  read(address,(int8_t *)cmd,size);
  
  memcpy(data,cmd,size);
  
  free(cmd);
  
}

/**
 * void clear(void)
 *
 * Clear eeprom (write with 0)
 * @param none
 * @return none
 */
void EEPROM::clear(void)
{
  int32_t data;
  uint32_t i;
  
  data = 0;
  
  for(i = 0; i < _size / 4;i++) {
     write((uint32_t)(i * 4),data);  
  }
}

/**
 * void ready(void)
 *
 * Wait eeprom ready
 * @param none
 * @return none
*/
void EEPROM::ready(void)
{
  int ack;
  uint8_t addr;
  uint8_t cmd[2];
  
  // Check error
  if(_errnum) 
    return;
  
  // Device address
  addr = EEPROM_Address | _address;
  
  cmd[0] = 0;
  
  // Wait end of write
  do {
       ack = _i2c.write((int)addr,(char *)cmd,0);
           //wait(0.5);
  } while(ack != 0);

}

/**
 * uint32_t getSize(void)
 *
 * Get eeprom size in bytes
 * @param  none
 * @return size in bytes (uint32_t)
*/
uint32_t EEPROM::getSize(void)
{
  return(_size);
}

/**
 * const char* getName(void)
 *
 * Get eeprom name
 * @param none
 * @return name (const char*)
 */
const char* EEPROM::getName(void)
{
  uint8_t i = 0;
  
  switch(_type) {
                  case T24C01 :
                                         i = 0;
                     break;
                  case T24C02 :
                                         i = 1;
                     break;
                  case T24C04 :
                                         i = 2;
                     break;
                  case T24C08 :
                                         i = 3;
                     break;
                  case T24C16 :
                                         i = 4;
                     break;
                  case T24C32 :
                                         i = 5; 
                     break;
                  case T24C64 :
                                         i = 6;
                     break;
                  case T24C128 :
                                         i = 7;
                     break;
                  case T24C256 :
                                         i = 8;
                     break;
                  case T24C512 :
                                         i = 9;
                     break;
                  case T24C1024 :
                                         i = 10;
                     break;
                  case T24C1025 :
                                         i = 11;
                     break;
  }
  
  return(_name[i]);
}

/**
 * uint8_t getError(void)
 *
 * Get the current error number (EEPROM_NoError if no error)
 * @param none
 * @return none
*/
uint8_t EEPROM::getError(void)
{
  return(_errnum);
}

/**
 * bool checkAddress(uint32_t address)
 *
 * Check if address is in the eeprom range address
 * @param address address to check (uint32_t)
 * @return true if in eeprom range, overwise false (bool)
*/
bool EEPROM::checkAddress(uint32_t address)
{
  bool ret = true;
  
  switch(_type) {
                  case T24C01 :
                     if(address >= T24C01)
                       ret = false;
                     break;
                  case T24C02 :
                     if(address >= T24C02)
                       ret = false;
                     break;
                  case T24C04 :
                     if(address >= T24C04)
                       ret = false;
                     break;
                  case T24C08 :
                     if(address >= T24C08)
                       ret = false;
                     break;
                  case T24C16 :
                     if(address >= T24C16)
                       ret = false;
                     break;
                  case T24C32 :
                     if(address >= T24C32)
                       ret = false;
                     break;
                  case T24C64 :
                     if(address >= T24C64)
                       ret = false;
                     break;
                  case T24C128 :
                     if(address >= T24C128)
                       ret = false;
                     break;
                  case T24C256 :
                     if(address >= T24C256)
                       ret = false;
                     break;
                  case T24C512 :
                     if(address >= T24C512)
                       ret = false;
                     break;
                  case T24C1024 :
                     if(address >= T24C1024)
                       ret = false;
                     break;
                  case T24C1025 :
                     if(address >= T24C1025 - 1)
                       ret = false;
                     break;
  }
  
  return(ret);
}