What I would like to do is make two MCUs (atmega328p) connected via Rx and Tx terminals read each others internal memory and copy the data to its own.
Example:
On MCU 1- Indentity = 123
On MCU 2- Indentity = 456
What I am aiming to achieve is for MCU 1 to read MCU 2s indentity of (456) and copy the code into its own memory. Having the ability to recall that MCU 2s identity = 456 even when the two are not connected.
MCU1 sends Identity data to MCU2. MCU2 reads it and saves it in its internal eeprom. MCU restarts and reads eeprom and loads the MCU1's Identity data to a variable and this will be available when MCU2 is running. After MCU2 reads and saves MCU1's data then MCU2 can send its data to MCU1.