What is the difference between `always_comb` and `always_comb` in SystemVerilog?

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Answered by suresh

Understanding the Difference Between `always_comb` and `always_latch` in SystemVerilog

When it comes to designing hardware circuits in SystemVerilog, it's essential to grasp the distinctions between `always_comb` and `always_latch` to ensure proper functionality and efficiency.

The Focus Keyword: SystemVerilog

`always_comb`: This keyword is used to define a block of sequential logic that executes continuously whenever any of its input signals change. It is primarily employed for combinational logic where the output is solely dependent on the current input values. The `always_comb` block is ideal for representing logic which should not have any clock or memory elements.

`always_latch`: On the other hand, `always_latch` is used to describe a block of logic that stores and updates state information based on specific conditions. It is commonly used for creating latches, which are sequential storage elements that maintain their output state until the input conditions change. Unlike `always_comb`, the `always_latch` block introduces memory elements into the design.

Therefore, the main difference between `always_comb` and `always_latch` in SystemVerilog lies in their respective functionalities: while `always_comb` is utilized for pure combinational logic without memory elements, `always_latch` is employed for sequential storage elements that require memory.

By comprehending the unique roles and applications of `always_comb` and `always_latch`, designers can effectively implement the desired logic in their SystemVerilog hardware designs.

Answer for Question: What is the difference between `always_comb` and `always_comb` in SystemVerilog?