Compare signals and variables in VHDL

1 Answer

Answer :

Sr. No
Signals
Variables
1 Signal objects are used to connect entities together to form model
Variables are used for local storage in process statements and subprograms.
2 Signals have their values scheduled in the future
Variables have all assignments to variables occur immediately
3 The keyword signal is followed by one or more signal names
The keyword variable is followed by one or more variable names
4 Signals can be declared in entity declaration sections architecture declarations and package declarations 
Variables can be declared in the process declaration and subprogram declaration sections only.
5 Signals need more information so more memory
Variables take less memory

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