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Combinational Logic
assign always @* always_comb blocking assignment ternary operator case casez casex caveat concatenation replication
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state parameter enum state state register next-state combinational Moore FSM Mealy FSM default state recovery one-hot state output register transition condition
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Advanced RTL
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Verilog / Testbenches

$readmemh

Learn $readmemh in Verilog through a focused explanation, a dedicated construct-specific example, an engineering boundary, and a mastery check.

10 min read • Advanced

$readmemh is an atomic Verilog topic inside Testbenches. This lesson focuses on how the $readmemh construct is written, what it changes, and when it is the right tool.

Trace the example line by line. Identify the exact syntax for $readmemh, the input state before it runs, and the resulting value, control flow, database state, hardware behavior, or runtime effect afterward. Neighboring lessons use different constructs rather than renamed copies of this one.

Topic-specific example

verilog-07-09-readmemh.sv
verilog Try It Live 
logic [7:0] rom[0:255]; initial $readmemh("rom.hex",rom);
Edge case / engineering note

For $readmemh, test the boundary that belongs to this exact feature rather than a generic failure case. Check invalid or empty input, NULL/unknown state, numeric limits, transaction or exception behavior, synthesis/runtime constraints, ownership/permission rules, or backtracking/control-flow effects where they apply.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

$readmemh Mastery Check →
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assert property