How many eeproms can be program together?

Using Arduino Programming Questions
1

Hello, I was wondering what is the maximum of eeprom's can be connected to an arduino? I know they are have addresses. As holding storage size I know they are not enough I was thinking of working on a crazy project with 10 of them. Is it possible from a programing point of view?

i know it would be easy to an SD card or a bigger capacity Fram or Mram. I just throught it be a cool project to use what I have now and learn. I don't have a project in mind it was just something I was thinking. Kind of like the old core memory from a long time ago.

Or is this post more for a project guideline area?

Joseph

2

Which external EEPROMs do you have in mind ?

3

EEPROM like the 24LC512 have only 3 pins for the I2C address so that gives you 8 possibilities only.

if you want more, you could use an I2C Multiplexer (like the TCA9548A)

4

Hey Bob, I have a box with like 50 of them different sizes. 5 of them for each size. I honestly haven't thought of how Something like this would come to life. It was just a wild thought really. I bought these for playing around with. They are way cheap. 10 dollars from ebay. I'm up for ideas on a crazy project with linking many of them. LOL

Joseph

5

I do have a couple of i2c switch chips not like this one I can use they have 8 channels on them. But that is a great idea Thank you, Now I have an idea on expanding to more later if I need to. I never thought of.

Joseph

6

You seem to have quite a collection of random-ish chips. Sometimes the best thing to do with them is throw them away and buy modern chips that actually fit your application.

(that said, I just came across some X2444 32 byte (!) nonvolatile memory chips in MY stash, and I didn't throw them away. I might have a problem.)

If they are I2C EEPROMs, there are (as has been said) usually a maximum of 8 I2C addresses that can be configured for each chip, so 8 is the "obvious" max. (less for smaller packages, or especially large I2C EEPROMs. 1Mbit I2C eeproms usually only have 2 usable address pins.)
But there are various tricks you can do to connect more than 8, such as connection one or more of the address select pins on the eeprom to pins on your microcontroller.

If you have SPI eeproms, you need a chip select for each one, and you should end up limited by the number of chip-selects you can generate. (again, there are tricks. 3pins can generate 8 chip-selects, if only one need be active at a time. But it probably requires additional external logic.)

7

I collected a lot of things over the years lol. some good some not LOL.

Joseph

8

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.