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Signal

Package, entity ve architecture yap覺lar覺n覺n i癟inde deklare edilebirler. Signal is a physical link (wire) that allows communication between the processes in architecture. It can be declared in any entity, architecture or package.

1

Signal Declaration

Signal name: type :=initial_value;

Example:

Signal reg :std_logic_vector(3 downto 0):=0000;

Signal Assignment

Signal assginment symbol (<=) is used to give a new value to a signal. It is similar to (=) operator that is used in any other programming languages like C/C++, Java.

All values:

Reg<=1111;
Reg<=xF;(hexadecimal)

One bit assignment:

Reg(2)<=0;

Bit slicing:

Reg(1 to 2)<=10;

NOTE:

Single-quote marks ( ) for bit assignments.

Double-quote marks (" ") for multi-bit assignments.

 

 

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