# EEPROM storing infromation?

Hello i have a question in programing and storing information to eeprom memory. My question is i have a i2c eeprom 256k chip on my uno board can i store all the information from all the digital pins and analog pins into the eeprom memory chip? want to store the information once every 30 seconds. problem is not sure how much can i store really i mean i know it will fill up the memory of the chip being it's only 256k but what i don't know is how long will it take to fill up can someone help me out on this?

One bit per digital pin, ten bits per analogue pin. Simple arithmetic.

And if it's too small, well it's a trivial matter to attach some more i2c eeprom externally.

thank you for the information i didn't know how many bites for the analog and digital now i got it.

But while it's true that a digital pin is a mere bit, won't you need to read a digital port (as opposed to pin) as a byte, else you'll end up writing a byte for each pin.

And the 10-bit analog pin is presumably going to cost 2x 8-bit bytes?

(At least, that's the way I see it.)

hello well this is what I'm trying to do i need to store analog pins 0,1,2,3 and digital pins 2,3,4,5,6,7,8,9 store the values that comes up trying to log voltages so it saves it to them pins once every 30 seconds. on the analog pins 4 of the 12v reading 4 of the 5.5v reading 3 of the 3v reading and 1 of the 1.5v reading to store them value into the eeprom from them pins. once every 30 seconds but i only read to read it like once a week or maybe once a month to read them as a log using the serial monitor.

JimboZA: But while it's true that a digital pin is a mere bit, won't you need to read a digital port (as opposed to pin) as a byte, else you'll end up writing a byte for each pin.

And the 10-bit analog pin is presumably going to cost 2x 8-bit bytes?

Not if you do things sensibly. You may waste four bits for all six analogue inputs (60 bits, next nearest is 64 bits == 8 bytes), but that's a saving over the twelve bytes you'd use otherwise. Depending on how many digital inputs you're saving, you may not waste even that much.

well honestly i just right now need a week worth of logging no more if the 256k is to low then i got a 1mb eeprom chip also. i didn't know if the 256k was enough or not..

So, how many readings in your target time period? How many bytes per reading? How many bytes available?

Simple arithmetic.