What does Access mean after dimensioning a variable?


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    Junior Member Dompie's Avatar
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    Default What does Access mean after dimensioning a variable?

    I know the System and Heap directive at the end of a variable declare i.e. Dim bVar as Byte System (or Heap).
    But in Les his WS2812B_Inc I discovered:
    Code:
    Dim WS2812B_bIndex    As Byte Access
    Dim WS2812B_bBitIndex As Byte Access
    Dim WS2812B_dRGB      As Dword Access
    As far as I understand:
    -System will create the variable at the begin of the Dim list.
    -Heap will create the variable at the end of the Dim list

    But does anybody know the meaning of Access?

    Johan

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    Senior Member Mellbreak's Avatar
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    Default Re: What does Access mean after dimensioning a variable?

    Now that is an interesting question, as I'm about to start playing with this program it would be good to know the answer to your question.

    Looking at the Proton manual, I can't find Access in the list of reserved words.

    Bob
    Last edited by Mellbreak; 4th December 2018 at 08:17.

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    Prolific Poster towlerg's Avatar
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    Default Re: What does Access mean after dimensioning a variable?

    It the first bank of RAM so it's quicker as no bank setting.

    See Microchip datasheet eg 18F25K50 and search for "Access Bank"
    Last edited by towlerg; 4th December 2018 at 12:41.
    George

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    Prolific Poster charliecoultas's Avatar
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    Default Re: What does Access mean after dimensioning a variable?

    Thanks George, that's useful to know.

    Charlie

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    Junior Member Dompie's Avatar
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    Default Re: What does Access mean after dimensioning a variable?

  6. Oh yes George that must be the solution!

    In the datasheet for 18F26K22 in 5.4:
    ""To ensure that commonly used registers (SFRs and select GPRs) can be accessed in a single cycle, PIC18 devices implement an Access Bank. This is a 256-byte memory space that provides fast access to SFRs and the lower portion of GPR Bank 0 without using the Bank Select Register (BSR).""

    I must read the datasheet better, I didn't know. Thanks!

    Johan

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