storing data from some other device through arduino to an external memory.

Projects General Guidance
1

Completely Newbie here. I am planning to connect an I2C memory to an arduino uno board. thereafter i want to code the arduino in such a way such that a device(connected to arduino) gives information to the arduino and arduino then stores the information in the external memory.What approach should i use ? Also, What is the size of the external memory i should use ? The information stored will be having basic string of information!(Roughly 200 characters). For initial testing, if i send use some command like

String.write ("--------") directly to the arduino and store into the memory. and then use some read command to display the same information on the serial monitor!

2
3

There's also the 24-series I2C eeproms, which are just as easy to use as the SPI ones - or easier.

The size of the external memory to use entirely depends on how much data you need to store - but it often doesn't cost much more to get a larger one.