How lasting is the EEPROM

Projects Programming
1

I know that write cycles is only 100 000 (if my memory serves me)

but if every 1 sec my sketch reads the same cell in eeprom, how long it will works?
I mean eeprom will be functional

2

I don't think reading causes any wear, only writing.

3

From a random data sheet:

So apparently about 100 years.

4

1000 000 for write I think its mistake

from datashett
Write/erase cycles: 10,000 flash/100,000 EEPROM

5

As others are pointing out, there's no 'wear' on an EEPROM if you're just reading it. However, you might want to test to see if there's a significant time difference between reading a memory variable, and reading an EEPROM location. If there is (I don't know the answer), you might want to read the EEPROM less frequently, storing the value in another variable.
I'm guessing you've got an asynchronous process(perhaps an interrupt?) that writes to the EEPROM without intervention from your main loop? FYI, the EEPROM write time is quite long, and therefore probably shouldn't be invoked in an interrupt.
C

6

you are right, I have no eeprom write within ISR

7

I am right, but you have no EEPROM write in the ISR? Please explain. Does that mean you're just storing a value and setting a flag in the ISR, then catching the flag in your main code somewhere and doing the EEPROM write there? But if that's the case, your main loop knows the value has changed already.
Confused,
C

8

You're looking at a different datasheet :wink:

Check the datasheet; for the 328P

9

I think in practice you will get well beyond the stated 100,000 write cycles.

10

Even writing reading it every second would take 2 weeks, which is already absurd, it took them several months. Never underestimate human stupidity. Just imagine you do RAM test on PC, come back next year and it is 98% complete, what a wonderful world that would be

11

I mean you r right - that I know that writing to eeprom is quite long... in my ISR I just working with flags