How to read/write beyond the first 256 bytes of EEPROM

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1

I am using an Ixora 1.3 board with Apalis iMX8 SOM.
According to an answer in this post, we “can use the EEPROM (AT34C02D-XHM-B 2-Kbit (256 x 8)) for your own needs. However we do not recommend to use the lower half (first 128 byte) if this EEPROM”
I am able to skip the reserved block and read/write the second 128 bytes no problem using

echo -n -e "{str}" | dd of=/sys/class/i2c-dev/i2c-4/device/4-0050/eeprom bs=1 seek=128 conv=notrunc

to write and

dd if=/sys/class/i2c-dev/i2c-4/device/4-0050/eeprom bs=1 skip=128 count=128 2>/dev/null

to read. However, I am not sure how to access the eeprom beyond the first 256 bytes.
TIA

3

The EEPROM is only 256 bytes in size, there is no additional storage.

Many manufacturers specify their EEPROM sizes in kilo (or mega) -bits, you need to divide this number (2kbit, or 2048 bit, in this case) by 8 to get kilobytes (256).

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4

If the EEPROM is limited to 256 bytes or 2-Kbit (256 x 8), it’s impossible to access any data beyond the first 256 bytes. Should you require additional storage, you have the option to install a larger EEPROM on your carrier board.