Datasheet

Adafruit_FRAM_I2C fram = Adafruit_FRAM_I2C();

Then when you begin(), pass in the i2c address. The default is 0x50 so if you don't put any

value in the default is used.

If you have different addresses, call something like

fram.begin(0x53)

for example.

Then to write a value, call

fram.write8(address, byte-value);

to write an 8-bit value to the address location

Later on of course you can also read with

fram.read8(address);

which returns a byte reading.