salvaged E2PROM chips - how useful are they ?

[lordvader88]

Like are little mini processors, or memory with a program, or both

for example, and old early 90s TV has a 8-DIP serial e2prom X24C00P
http://pdf1.alldatasheet.com/datasheet-pdf/view/34173/XICOR/X24C00P.html

Can something like that be taken and put to use doing whatever, in the same way I could look up 100s of 555 circuits.

I'm going to look what its connected to

[jaromir]

Unlike 555, which is univesal by design and can be forced to do whatever from multivibrators to almost-analog circuits, this is IIC EEPROM, which is designed and can be... IIC EEPROM. It doesn't even have address and WP inputs, which could somehow increase the amount of combinations (not all of them useful, though) you can do with it.
Being it parallel EEPROM, it would be not as much hopeless.
You can use it as it is designed, but 128B worth of EEPROM is hardly any interesting capacity those days.

But you can drill it through and make necklace for your girlfriend/wife/whatever.

[Ian.M]

Just about the only remaining use for low capacity I2C EEPROM is identifying interchangeable removable cards or modules to the host MCU, or storing their calibration parameters.  An example is VGA, DVI and HDMI monitors with DDC2B.
However its generally preferable to have a write protect pin on the EEPROM so the key I.D data can be protected against corruption. 

An X24C00P is basically useless to you unless you are repairing something that needs one or are into MCU programming and want to practice coding low-level I2C access routines for small EEPROMs.

[amyk]

But you can drill it through and make necklace for your girlfriend/wife/whatever.

...or leave it usable, and write a message to it. 128B is not a lot but this post is only 94B.

[lordvader88]

ok and it seems this particular 1 has most functions disabled or just cut off and not wired to the outside anymore.

I'm way behind on digital, logic and especially programmable stuff and programing in general. For a little while I was learning Python and fooling around with an Ardino, but that was 3-4 years ago ?? wow that was a long time ago, and I never touched it since, but I'm only getting serious about EE this past few months

[jaromir]

I have another idea - write message into the EEPROM, put into sealed bottle and throw into ocean. Message in the bottle, 1990's style.

[Ian.M]

A 128 bit EEPROM wont store much of a message. even in 5 bit Baudot code.

[jaromir]

My mistake, I thought it's 128 bytes, not bits - as you correctly pointed out. In 5-bit code it is 25 characters, not too much; unless one is haiku lover.