GY-63_MS5611/libraries/I2C_EEPROM

I2C_EEPROM

Arduino Library for external I2C EEPROM - 24LC512, 24LC256, 24LC64/32/16/08/04/02/01

Description

This library is to access external I2C EEPROM up to 64KB (= 512 Kbit) in size. MicroChip 24LC512, 24LC256, 24LC64, 24LC32, 24LC16, 24LC08, 24LC04, 24LC02, 24LC01 and equivalents.

The I2C_eeprom_cyclic_store interface is documented here

Interface

Constructor

• I2C_eeprom(uint8_t deviceAddress, TwoWire *wire = &Wire) constructor, optional Wire interface
• I2C_eeprom(uint8_t deviceAddress, uint32_t deviceSize, TwoWire *wire = &Wire) constructor, with optional Wire interface.
• bool begin() initializes the I2C bus and checks if the device is available on the I2C bus.
• bool begin(uint8_t sda, uint8_t scl) idem for ESP32 / ESP8266 and alike.
• bool isConnected() test to see if device is on the bus.

Core functions

• int writeByte(uint16_t memoryAddress, uint8_t value) write a single byte to the specified memory address.
• int updateByte(uint16_t memoryAddress, uint8_t value) write a single byte, but only if changed. Returns 0 if value was same or write succeeded.
• int writeBlock(uint16_t memoryAddress, uint8_t * buffer, uint16_t length) write a buffer starting at the specified memory address.
• int setBlock(uint16_t memoryAddress, uint8_t value, uint16_t length) writes the same byte to length places starting at the specified memory address. Returns 0 if OK.
• uint8_t readByte(uint16_t memoryAddress) read a single byte from a given address
• uint16_t readBlock(uint16_t memoryAddress, uint8_t * buffer, uint16_t length) read length bytes into buffer starting at specified memory address. Returns the number of bytes read, which should be length.

Other

• uint32_t getDeviceSize() idem
• uint8_t getPageSize() idem
• uint8_t getPageSize(uint32_t deviceSize) idem
• uint32_t getLastWrite() idem
• uint32_t determineSize(bool debug = false)
  function that determins the size of the EEPROM by detecting when a memory address is folded upon memory address 0. It is based upon the observation that memory wraps around. The debug flag gives some output to Serial.

Warning: this function has changed (again) in 1.4.0

Testresults

Type	returns	Memory	Page Size	Notes
-	0			connect error, check device address / wiring
24LC512	65536	64 KB	128
24LC256	32768	32 KB	64
24LC128	16384	16 KB	64
24LC64	8192	8 KB	32
24LC32	4096	4 KB	32	not tested with hardware
24LC16	2048	2 KB	16
24LC08	1024	1 KB	16
24LC04	512	512 b	16
24LC02	256	256 b	8
24LC01	128	128 b	8

The function cannot detect smaller than 128 bit EEPROMS.

Limitation

The library does not offer multiple EEPROMS as one continuous storage device.

Future

• improve error handling, write functions should return bytes written or so.
• what can we do with the print interface? (investigate)
• investigate multi-EEPROM storage,

Operational

See examples