Microchip EEPROM library

Arduino library for Microchip EEPROMs (24...)

Features

• read/write single byte
• read/write page of bytes
• updated bytes/pages
• Works on AVR and RP2040 based boards (Arduino Uno, Nano, Mega, ... and Raspberry Pi Pico, RP2040)

Usage

Initialize EEPROM:

EEPROM_Microchip_24 eeprom(<address>, <highestAddress>, <sdaPin>, <sclPin>, <maxPageWrite>);

• address: i2c address of eeprom chip. (set by A0, A1, A2 pins)
• highestAddress: highest memory address of eeprom (64 KBit = 0x1FFF)
• sdaPin: pin of sda pin (only for boards that support different i2c pins)
• sclPin: pin of scl pin (only for boards that support different i2c pins)
• maxPageWrite: maximum number of bytes that can be written at once (32 for the 64 KBit version)

Initialize EEPROM:

EEPROM_Microchip_24 eeprom(<addressBits>, <highestAddress>, <sdaPin>, <sclPin>, <maxPageWrite>);

• addressBits: last three bits of address in array (A0, A1, A2) e.g. {0, 0, 0}
• highestAddress: highest memory address of eeprom (64 KBit = 0x1FFF)
• sdaPin: pin of sda pin (only for boards that support different i2c pins)
• sclPin: pin of scl pin (only for boards that support different i2c pins)
• maxPageWrite: maximum number of bytes that can be written at once (32 for the 64 KBit version)

Write single byte

eeprom.writeByte(<address>, <data>);

• address: the memory address of the byte (e.g. 0xFF)
• data: 8-bit data that should be stored

Returns true or false depending on whether it was successful or not.

Write page of bytes

eeprom.writePage(<startAddress>, <data>, <dataLength>);

• startAddress: the memory address for the first byte (e.g. 0xFF)

• data: array of 8-bit data

• dataLength: the size of the data array (number of bytes)

  Returns true or false depending on whether it was successful or not.

Read single byte

eeprom.readByte(<address>);

• address: the memory address of the byte (e.g. 0xFF)

Returns the 8-bit data of the given address.

Read multiple bytes

eeprom.readSequentialByte(<startAddress>, <length>);

• startAddress: the memory address of the first byte to read (e.g. 0xFF)
• length: number of bytes to be read

Return a pointer to an array of 8-bit data with the given size.

Update single byte

eeprom.updateByte(<address>, <data>);

• address: the memory address of byte (e.g. 0xFF)
• data: data that should be written to the given address

Returns true or false depending on whether the byte was changed or not.

Update multiple bytes

eeprom.updatePage(<startAddress>, <data>, <length>);

• startAddress: the memory address of the first byte (e.g. 0xFF)
• data: data array of 8-bit data that should be written to the given address
• length: the size of the data array (number of bytes)

Returns true or false depending on whether a byte was changed or not.

Notes

• update should be executed instead of write, because EEPROM has only limited write cycles
• Tested on Raspberry Pi Pico and Arduino Uno
• Only tested with the 64-KBit version (24LC64) but should also work on all other capacities