SystemC Simulation std_ulogic <= std_ulogic ------------------------------------------- UNINITIALIZED = X 'U' UNKNOWN = X 'X' ZERO = 0 '0' ONE = 1 '1' TRISTATE = Z 'Z' WEAK-UNKNOWN = X 'W' WEAK-ZERO = X 'L' WEAK-ONE = X 'H' DONT-CARE = X '-' TRUE = 1 true FALSE = 0 false std_ulogic <= literals ------------------------- A = 1 true B = 0 false C = 1 1 D = 0 0 std_ulogic <= bool --------------------- TRUE = 1 1 FALSE = 0 0 1 = 1 1 0 = 0 0 std_ulogic <= char --------------------- SC1 = X 'U' SC2 = X 'u' SC3 = X 'X' SC4 = X 'x' SC5 = 0 '0' SC6 = 1 '1' SC7 = Z 'Z' SC8 = Z 'z' SC9 = X 'W' SC10 = X 'w' SC11 = X 'L' SC12 = X 'l' SC13 = X 'H' SC14 = X 'h' SC15 = X '-' SC16 = X 'D' SC17 = X 'd' SC18 = X 'B' SC19 = X 'F' op1 operator op2 result [All operands are std_ulogic] ---------------------------------------------------------------- 1 &= 1 = 1 1 ^= 1 = 0 1 |= 1 = 1 ~(1) = 0 1 & 1 = 1 1 ^ 1 = 0 1 | 1 = 1 1 == 1 -> true 1 != 1 -> false 0 = 0 +-------------------------+ | AND (&) | X | 0 | 1 | Z | +-------------------------+ | X | X | 0 | X | X | +-------------------------+ | 0 | 0 | 0 | 0 | 0 | +-------------------------+ | 1 | X | 0 | 1 | X | +-------------------------+ | Z | X | 0 | X | X | +-------------------------+ +-------------------------+ | OR (|) | X | 0 | 1 | Z | +-------------------------+ | X | X | X | 1 | X | +-------------------------+ | 0 | X | 0 | 1 | X | +-------------------------+ | 1 | 1 | 1 | 1 | 1 | +-------------------------+ | Z | X | X | 1 | X | +-------------------------+ +-------------------------+ | XOR (^) | X | 0 | 1 | Z | +-------------------------+ | X | X | X | X | X | +-------------------------+ | 0 | X | 0 | 1 | X | +-------------------------+ | 1 | X | 1 | 0 | X | +-------------------------+ | Z | X | X | X | X | +-------------------------+ +-------------------------+ | NOT (~) | X | 0 | 1 | Z | +-------------------------+ | | X | 1 | 0 | X | +-------------------------+