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TOPIC: EEPROM, writing and reading..

Re: EEPROM, writing and reading.. 8 years 2 months ago #15824

  • RogerTango
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In the Proton manual, its says its not "healthy" to write to the EEPROM "too much".

What *IS* "too much"?

I was planning on using what I could as a limited data logger...

Im glad to see my 18F25K22 has 1K EEPROM.

While Im on topic, is there any precautions I should take note of to preserve the EEPROM? Anything I can do with variables or program size that would interfere with it?

Thanks,
Andrew

Re: EEPROM, writing and reading.. 8 years 2 months ago #8507

  • be80be
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You can easily ware it out in a week or less

It has 1 million cycles

Re: EEPROM, writing and reading.. 8 years 2 months ago #8508

  • RogerTango
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You can easily ware it out in a week or less

This was all I saw at the bottom of the screen, I had to scroll up to see the rest..

I about had a heart attack!

Thanks for the info bud!
Andrew

Re: EEPROM, writing and reading.. 8 years 2 months ago #8503

  • Jon Chandler
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This is another example of a good place to consult the data sheet.

It's not too hard to find. Section 5 is called Data EEPROM Memory. Start there.

From the data sheet:
5.0 DATA EEPROM MEMORY
The data EEPROM is a nonvolatile memory array, separate from the data RAM and program memory, which is used for long-term storage of program data....

The EEPROM data memory is rated for high erase/write cycle endurance. A byte write automatically erases the location and writes the new data (erase-before-write). The write time is controlled by an on-chip timer; it will vary with voltage and temperature as well as from chip-to-chip. Please refer to parameter US122 (Table 25-13 in Section 25.0 “Electrical Specifications”) for exact limits.

So it's on to section 25. If we look through the tables, section 25-10 contains what we're looking for (yes, there is a typo in section 5 of the data sheet).



Finding the answer in the data sheet should be faster than posting a question here and waiting for a reply. The data sheet is the ultimate authority, and you may find that the answers posted here aren't always correct.

From the data sheet, two parameters are given]new.digitaldiy.io/images/icon_e_smile.gif[/img]

Keep in mind too that these are the minimum number of cycles before errors may start to occur. A small percentage of chips will fail at this point. Many may have a higher endurance limit.
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Re: EEPROM, writing and reading.. 8 years 2 months ago #8514

  • RogerTango
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Very good information on the data sheets, your explanation was very helpful to understanding what is printed.

With constructive criticism I have learned a LOT here, not because the information was always spoon fed, but because more often than not Ive been given just enough information to steer me in a more correct direction.

For example, I had been having a devil of a time trying to figure out how to config the internal clock settings. Ive taught myself how to look up the oscillator settings in the data sheet and set the bits as needed.

I am thankful the the forum and the members.
Andrew

Re: EEPROM, writing and reading.. 8 years 2 months ago #8515

  • W4GNS
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I take it that you are aware that there is a Fuse Configuator Mk2 plugin for Proton that makes life O so easy, correct ? It's free BTW

OPf course you still need to be intimate with the datasheets

For example, I had been having a devil of a time trying to figure out how to config the internal clock settings. Ive taught myself how to look up the oscillator settings in the data sheet and set the bits as needed.


Andrew
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