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  Mem[ segment:offset ]
  MemW[ segment:offset ]
  MemL[ segment:offset ]
 
  Unit:      System (used automatically)
 
  See also:  Port, PortW
 
  Description
 
    Three predefined arrays are available for accessing memory directly.
    Mem accesses bytes, MemW accesses words, and MemL accesses long
    integers. The syntax for these arrays is different from normal
    arrays. Specify both a segment and an offset part, separated by a
    colon. The arrays can be used either for reading from memory or for
    writing to memory. Writing directly to memory is a potentially
    dangerous technique that should be used with care.
 
    Some examples are shown below:
 
       { Turn on CAPSLOCK by setting bit 6 at $40:$17. }
       Mem[$40:$17] := Mem[$40:$17] OR $40;
 
       { Assign clock ticks past midnight to a long integer variable. }
       ticks := MemL[$40:$6C];
 
       { Write attribute $2F, character $01 to color screen buffer. }
       MemW[$B800:0] := $2F01;