Continuous assignment

assign A = X | (Y & ~Z);

assign B[3:0] = 4'b01XX;

assign C[15:0] = 4'h00ff;

assign #3 {Cout, Sum[3:0]} = A[3:0] + B[3:0] + Cin;

arithmetic operator

multiple assignment (concatenation)

Gate delay (only used by simulator, not during synthesis)

Boolean operators(~ for bit-wise negation)

bits can assume four values(0, 1, X, Z)

variables can be n-bits wide(MSB:LSB)

• Assignment is continuously evaluated

  • Corresponds to a connection or a simple component
  • Target is not a reg variable

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