ModuleWare Reference Guide - Hornad

Primitive PartsIntroductionThe strength1 or strength0 specification, which specifies the strength of an output signal with avalue of 1 and 0 respectively uses one of the following keywords:Table 10-1. Keywords of Drive Strength SpecificationsStrength nameStrength levelNoneSupply0Strong0Pull0Weak0Highz0Highz1Weak1Pull1Strong1Supply1NoneThe strength specification follows the gate type keyword and precedes any delay specification.The strength0 specification follows the strength1 specification. You should not enter thefollowing strength combinations (HighZ0, HighZ1) and (HighZ1, HighZ0). An error would begenerated if either of these combination is assigned for a particular gate instance.In VHDL, these strength specifications are mapped to the IEEE-1164 standard, which consistsof nine values (0, 1, L, H, W, U, X, - and Z).This mapping is shown in the following table:Table 10-2. Strength Specifications Mapped to IEEE-1164 StandardStrength name Logic level Mapped levelNoneSupply0 0LStrong0 0LPull0 0LWeak0 0LHighz0 0LHighz1 1H4321001234000000LLZZZZModuleWare Reference Manual, Library Version 1.9 231September 18, 2008