Definition
A basic operation that combines one or more values into a composite value of a record or array type.
Example 1
variable Data_1 : BIT_VECTOR (0 to 3) := ('0','1','0','1');
Example 2
variable Data_2 : BIT_VECTOR (0 to 3) := (1=>'1',0=>'0',3=>'1',2=>'0');
bits 0 and 2 are assigned '0', while bits 1 and 3 are assigned '1'.
Example 3
signal Data_Bus : std_logic_vector (15 downto 0); ... ... Data_Bus <= (15 downto 8 => '0', 7 downto 0 => '1');
Data_Bus will be assigned "0000_0000_1111_1111".
Example 4
type Status_Record is record Code : Integer; Name : String(1 to 4); end record; variable Status_var : Status_Record := (Code => 57, Name => "MOVE");
each element is associated a value (of the same type as the element itself).
Example 5
signal Data_Bus : std_logic_vector (15 downto 0); ... ... Data_Bus <= (14 downto 8 => '0', others => '1');
bits 14 through 8 receive value '0' and all the others (15 and 7 through 0) will be assigned '1'.
Example 6
signal Data_Bus : std_logic_vector (15 downto 0); ... ... Data_Bus <= (others => 'Z');
aggregate with the others choice representing all the elements can be used.
Example 7
signal Data_Bus : std_logic_vector (15 downto 0); ... ... Data_Bus <= (15 | 7 downto 0 => '1', others => '0');
Note the multiple choice specification of the assignment to the bits 15 and 7 through 0. The result of the assignment to Data_Bus will be the same as in examples 3 and 5 ("1000_0000_1111_1111").