I2CWRITE writing Strings to EEPROM

[mister_e]

Not at this point, many stuff to be finished before... still need time.

i've plan a program to edit EEPROM that allow to move/insert/delete EEPROM addresses. Handy IMO.

I've a snippet that work, I'll let you know as soon as it's finished.

[Tom Gonser]

Using the same 25LC512 EEPROMs, I have a similar issue I think...

I write 36 bytes per record which I get every .25 seconds.. maybe faster. I want to write these to EEPROM, but not take a whole page (128b). I understand I can't write to addresses in the size I want, ie 0, 36, 72, 108, 144, etc, but rather only 0, 128, 256, etc.... This leads to massive waste of space

How does one make use of the unused EEPROM space? I can't write byte at a time because it takes too long...

1. If I page write to anything from 0 to 128 will it overrite that page?

2. Should I be thinking about a way to save data into a string that is 128b long before writing it? Like perhaps creating a 'superstring' that has 3 x 36 bytes, and write that (only wasting 20b per page?)

Thanks,

Tom

[NavMicroSystems]

TOM,

you haven't told us all details,
but let's do some math based on the info we have:

36 bytes per record
one record every 250 ms
EEPROM size 512kbit

You can store about 1770 records
It will take about 7.5 minutes to completely fill up your EEPROM.

Probably FRAM would be a better choice.

[Tom Gonser]

Ralph:

Be happy to fill in any gaps, I was trying to be as complete as I could without using too much junk..

You are right about 7.5 min per chip if I can not waste any space.. Two chips = 15 min at that rate, at 1 second update much more.

I am not familiar with FRAM.. How is it used? Does PBP work easily with it?

Tom

[Archilochus]

I am not familiar with FRAM.. How is it used? Does PBP work easily with it?
Tom

The FRAM is great! Virtually unlimited write cycles, writes data as its clocked in with no write delay, single byte writes, available in SPI, I2C etc.
Check out Ramtron.

Arch

[NavMicroSystems]

TOM,

FRAM is handeled just like EEPROM (I2C)

have a look at www.ramtron.com