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Altera_Forum
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11 years ago

tcl commands

For master_write_32 $master_path [expr $base_reconfig + 0x40*4], can anybody tell me what *4 means exactly? Thanks

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  • Altera_Forum's avatar
    Altera_Forum
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    --- Quote Start ---

    For master_write_32 $master_path [expr $base_reconfig + 0x40*4], can anybody tell me what *4 means exactly? Thanks

    --- Quote End ---

    Avalon-MM master addresses are 32-bits wide. The address map for the reconfiguration controller probably has the register offsets in words, i.e., the register located at 32-bit word offset 0x40 is located at byte offset 4*0x40.

    If the address map for the reconfiguration controller is already in byte offsets, and the register you want to access is at byte-offset 0x40, then the 4* would be unnecessary.

    Cheers,

    Dave
  • Altera_Forum's avatar
    Altera_Forum
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    Thanks, Dave.

    * here doesn't mean multiply. So 4*0x40 = 0x00000040. Is that correct?
  • Altera_Forum's avatar
    Altera_Forum
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    --- Quote Start ---

    here doesn't mean multiply. So 4*0x40 = 0x00000040

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    The Tcl command expr means "do some math", so 4*0x40 = 0x100 :)