arraywrite takes too much memory, is there any way for optmisation?


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  1. #1
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    Default arraywrite takes too much memory, is there any way for optmisation?

    Hello.
    I'm building an educational device, which has a lot of text to display.
    Using ST7920 with own "library" to have 8 lines of 16 characters on 128x64 pixels screen.
    The issue is, that arraywrite/read takes too much memory. For example, the code below takes about 400 bytes of memory.

    Code:
    if dta>olddta then arraywrite topline, ["trendi:","a]mavali          "]
    if dta<olddta then arraywrite topline, ["trendi:da]mavali           "]
    if dta=olddta then arraywrite topline, ["trendi:stabiluri           "]
    olddta=dta
    Is there any other way for storing large text lines like this? (other than using internal/external EEPROM) ?

  2. #2


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    Default Re: arraywrite takes too much memory, is there any way for optmisation?

    What device are you using?

  3. #3
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    Default Re: arraywrite takes too much memory, is there any way for optmisation?

    nothing has changed since last time you asked the same question
    http://www.picbasic.co.uk/forum/showthread.php?t=24442
    Warning I'm not a teacher

  4. #4
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    Default Re: arraywrite takes too much memory, is there any way for optmisation?

    I'm using PIC16F1939, as the biggest memory (16K and fastest (32mhz) in 16F family.
    I just came to idea - since reading external EEPROM is quite slow
    what if I use some SRAM chip, with parallel access, like CY7C199, copy data from EEPROM to it at startup, and access it as required?

  5. #5
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    Default Re: arraywrite takes too much memory, is there any way for optmisation?

    15 address pins
    8 bidirectional i/o pins
    r/w control pin
    oe pin
    ce pi
    hope you don't want the pic to do much else other than be a pin jockey for all them controls

    and you think that will be easier to get going than learning to use flash memory
    Warning I'm not a teacher

  6. #6
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    Default Re: arraywrite takes too much memory, is there any way for optmisation?

    Yes it will take a lot of pins.
    I'm using I2CREAD/I2CWRITE w/o any issues, but it is slow.

  7. #7
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    Default Re: arraywrite takes too much memory, is there any way for optmisation?

    Flash memory is more manageable as Richard noted.

    Observe how selected PIC is controlling read/write pages and do it nice and fast.

    Ioannis

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