low attribute

[John Smith]

The low attribute can be used for multidimensional arrays? What will it
result?

For example:
architecture arch of test is
TYPE stdlogic_table IS ARRAY(std_ulogic, std_ulogic) OF std_ulogic;
begin

process
variable s: stdlogic_table;
variable i: std_logic;
begin
i := s'LOW;
wait;
end process;

end arch;

Thanks

 

[Jonathan Bromley]

The low attribute can be used for multidimensional arrays?

Yes.

A slightly more interesting example than yours (different
subscript types for the two dimensions):

type big_array is array (boolean, integer range 0 to 9) of std_logic;
....
....
variable s: big_array;
....

Now, S'LOW(1) = FALSE, S'LOW(2) = 0. All the array attributes
have an optional argument specifying which dimension you're
inquiring about; 1 specifies the first dimension.

And S'LOW is exactly S'LOW(1) by definition.
--
Jonathan Bromley, Consultant

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