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EEPROM

Discussion in 'Microcontrollers' started by bogdanfirst, Mar 20, 2003.

  1. bogdanfirst

    bogdanfirst New Member

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    can i use a PIC12Cxx eprom to save a text file on it? and then read it?
    also, are these PIC's erasable and rewritable?
     
  2. kinjalgp

    kinjalgp Active Member

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    Yes you can do it. But most of the PICs don't have much EEPROM memory (around 1-2k). A better thing you can do is hook up a bank of eight 24LC256 I2C EEPROMs to PIC12Cxx and you will have a 32k x 8 = 256kB of NV memory. I think the 12Cxx versions are OTPROM type and you can't erase them once programmed.
     
  3. Chippie

    Chippie New Member

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    The /Jw version is the reprogrammable type but requires a UV source to erase it
     
  4. dave

    Dave New Member

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  5. bogdanfirst

    bogdanfirst New Member

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    yes i know about the UV....
    but where do i find an UV light source?
    can a quartz lamp work? i don't know how it is somebody said that has one and might give it to me....
     
  6. Chippie

    Chippie New Member

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    The Sun is an excellent source of UV........ :lol:

    seriously tho' I built an eraser from a 12in strip light and used a germicidal tube ILO the fluorescent tube......when you erase the chip do not over expose it or else you will turn it into a prom!
     
  7. kinjalgp

    kinjalgp Active Member

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    If you think you can erase EPROM under the sun, you'll have to wait for a year to get the job done. :)
     
  8. bogdanfirst

    bogdanfirst New Member

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    that's what i thought too....
    i left some for a full day under complete sun and nothing.......
    maybe it will work fater if i could focus the light with a lens and use a UV filter so that the IR will not pass and heat it too much.....
    maybe i can find some UV lights at normal light shops? Philips maybe?
     
  9. kinjalgp

    kinjalgp Active Member

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    I bought my UV lamp from industrial light-fittings store but I never got a chance to use it :( since I got with the newer uCs with FLASH ROMS. Inspite of having a huge flock of EPROMS I have never put a single chip to any practical purpose.
     
  10. bogdanfirst

    bogdanfirst New Member

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    what kind do you use....?
    what is the hightest capacity of an (E)EPROOM?
    and FLASH?
     
  11. kinjalgp

    kinjalgp Active Member

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    The size of external FLASH ROMS I use are limited by the bus-width of the uC's I use (normally 80C51). But this is a very rare case when I use external memories. All new uCs come with lot of internal program memory (64kB) which is more than enough for any complex application. And if you want more there are variants of 8051 (one from winbond) which can access 1MB of program memoy. WOW!

    Talking about sizes in which FLASH memories are available SAMSUNG has 1Gbit to offer!
     
  12. kinjalgp

    kinjalgp Active Member

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  13. bogdanfirst

    bogdanfirst New Member

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    yes, i know about the high capacity of flash memories....i have a digital camera that suppots up to 300M!! but i has just an 8M card..... :( :( :(
    whay dont you try and use a 1Gb of memory for a led project....:)
     
  14. kinjalgp

    kinjalgp Active Member

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    Whats the use of such large memory in LED project?
    Even if you use it to store LED sequences, even the smallest I2C EEPROM i.e 24C02 does the job. You have enough memory to store 128 different seqeunce bytes.
     
  15. bogdanfirst

    bogdanfirst New Member

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    well i was just saying that as a small joke, that's what i though of...you can store hours of sequences................................:):):)
     
  16. arcom

    arcom New Member

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    Here is a quick calculation of my own :D :

    1 GB = 1073741824 bytes (note: use 1 byte for 1 sequence)
    Provided that you display each sequence every 0.5 seconds, you can store up to 536870912 seconds of "animation". If you convert this to hours (better to years, lol), you get the following:
    34,05 years of animated sequences :lol: :lol: :lol:
     
  17. kinjalgp

    kinjalgp Active Member

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    Well, thats a good idea if you want your grand-grand-grand.............sons to remember you :lol:
     
  18. bogdanfirst

    bogdanfirst New Member

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    well, probable they will use a 1 GB memory as we use a 1KB memory....
     
  19. arcom

    arcom New Member

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    Or, as our math professor once said, they will have ICs in their heads :D
     
  20. bogdanfirst

    bogdanfirst New Member

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    well, i dont agree with circochip implants....however they will help.....
    we need to learn to master our brain, it has a memory capacity of 10^20 bits...wich compared to a computer memory it is ......HUGE!
    plus that the processing capacity is far better than a Gibson computer.
    but the fact is that very few of the people use more than 10% of there memory in their lifetime and hardly you find someone that uses more than 1% of the processing capacity.
    so think that you copuld use your barain even at the double capacity that you use now, not to say about using 100% of it.(maybe some overclocking could do and we could use more than 100% :D :D ).
    so the problem is to use our brain better, not to build faster computers....or maybe make them interact together.....better
     
  21. kinjalgp

    kinjalgp Active Member

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    Bogdan, can you solve 1236548782484 * 3269754666564 in fraction of a second? NO
    But a small computer with thousands of time less processing power than human brain can do it.
    So what is that which matters more? Speed or processing power?

    I think it is speed!
     

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