What is Nonblocking assignment?
Verilog's "<=" assignment, which evaluates every right-hand side at a time step before updating all left-hand sides together. It matches flip-flop behavior and is used for sequential logic.
Field: HDL & Verification
Nonblocking assignment in the explanations
With nonblocking assignment, at the clock edge every <= right-hand side is first evaluated using the old values, and only then are all left-hand sides updated together.
How does Verilog's nonblocking assignment (<=) behave?With nonblocking assignment, both right sides (b's old value 1 and a's old value 0) are evaluated first, then a gets 1 and b gets 0 simultaneously, so they swap.
In the code above, a = 0 and b = 1 just before a rising clo…
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