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How to use extra EEPROM for storage? — Parallax Forums

How to use extra EEPROM for storage?

DouglasDouglas Posts: 8
edited 2009-03-29 05:33 in BASIC Stamp
Hi,

· I'd like to use an external EEPROM for data storage.· I have a couple 93LC66A's, but there are no examples on how
to write a program for the BS2.· Is using a 93LC66 a good choice or is there a better EEPROM to use for external storage?
Any assistance would be greatly appreciated.

Doug

Comments

  • Mike GreenMike Green Posts: 23,101
    edited 2009-03-27 20:09
    There are much newer EEPROMs with SPI interfaces like the 93LC66A. I'd suggest looking at the 25LC1024 from Microchip. This holds 128K bytes of information and, like the 93LC66A, can be accessed using the SHIFTIN / SHIFTOUT statements for the clock and data lines and HIGH / LOW for the chip select line. The commands are a little different, but the datasheet for both devices has a lot of information you'll need. Look at them. Since you have the 93LC66A, if it's big enough for your needs, you might as well use it. If it's not really big enough, by all means go for the 25LC1024.
  • DouglasDouglas Posts: 8
    edited 2009-03-28 01:30
    Hi again,

    · I have a 93LC66A.· I'm trying to convert old BS1 code to work with my BS2.· It's very painful at this point.· My overall goal for data storage is to be able to use my PING DAR with COMPASS and store angles and distances in EEPROM.· I'm trying to find a good EEPROM solution.· It appears the StampMEM was taking off the market.· I'm not sure if the USB Memory module will work.· I only was trying to use the 93LC66A because I had two of them sitting around.· If there is something that is better for what I want, I'll try it.· For right now I'm just trying to get code to work with the 93LC66A.· Once again, any assistance would be greatly appreciated.



    Doug
  • Mike GreenMike Green Posts: 23,101
    edited 2009-03-28 03:52
    How about posting your code (as an attachment to your message)?
  • DouglasDouglas Posts: 8
    edited 2009-03-29 00:05
    Hi,

    · Here is the best I've found.· It appears to erase the chip.· I'd like to take data from a debug input and write it to the chip, them read it back.· Once again, any assistance would be greatly appreciated.

    Doug
    bs2
    bs2
    eeprom.bs2
    3K
  • Mike GreenMike Green Posts: 23,101
    edited 2009-03-29 01:22
    The routines you found are for a different EEPROM like a 25LC512 or 25LC256. They won't work for a 93LC66A. I don't have a link to routines that would work for a 93LC66A.
  • Beau SchwabeBeau Schwabe Posts: 6,559
    edited 2009-03-29 05:33
    Douglas,

    Here is some DEMO code I just put together based on the BS1 application notes - #13. The DEMO code basically runs through a few patterns by writing them to the EEPROM and then reads the value back for a Pass/Fail indication.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Beau Schwabe

    IC Layout Engineer
    Parallax, Inc.
    bs2
    bs2
    93AA66A.bs2
    4K
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