Arduino7:
I'm quite new to Arduino programming and have a similar problem with storing values.
I want the user to select a number from the LCD shield I have and then as they press SELECT the number is stored e.g Value = Machine Number, and then I could use it later on.
Is this possible?
Could someone help?
Most Arduino microcontrollers have a built-in EEPROM as a non-volatile storage area. An UNO has 1KB = 1024 bytes EEPROM, so you could save up to 256 'long' variables in the EEPROM.
The programming logic would be, that the setup() function reads the stored EEPROM values into RAM variables, and when the number is entered you store the number in the RAM variable as well as in the EEPROM.
The EEPROM memory has limited write cycles for each of the memory bytes (I think Atmel guarantees 10000 writes at least), but the number of read cycles is unlimited. So the EEPROM is a suitable storage area for variables that do not change very often (at most a few times per day, perhaps), but not for fast changing values that changes in intervals of seconds.