26 lines
997 B
Plaintext
26 lines
997 B
Plaintext
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Important Coding Guidelines with Nonblocking Assignments
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From Clifford E. Cummings paper: Verilog Nonblocking Assignments With Delays,
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Myths & Mysteries.
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http://www.sunburst-design.com/papers/CummingsSNUG2002Boston_NBAwithDelays.pdf
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Guideline #1: When modeling sequential logic, use nonblocking assignments.
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Guideline #2: When modeling latches, use nonblocking assignments.
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Guideline #3: When modeling combinational logic with an always block, use blocking
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assignments.
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Guideline #4: When modeling both sequential and combinational logic within the same always
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block, use nonblocking assignments.
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Guideline #5: Do not mix blocking and nonblocking assignments in the same always block.
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Guideline #6: Do not make assignments to the same variable from more than one always block.
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Guideline #7: Use $strobe to display values that have been assigned using nonblocking
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assignments.
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Guideline #8: Do not make assignments using #0 delays.
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