1 The simulation model consists of components connected by wires.
2 Some components consist of other components and wires. The components contained in such a component are called the subcomponents of this component.
3 Some wires carry one bit, and some carry multiple bits.
4 Each bit carried by a wire is one of 1, 0, U, Z, or X. These values are IEEE 1164-compilant. (We don't use H, L, or W.)
5 See https://en.wikipedia.org/wiki/IEEE_1164 for an explanation of these values.
6 Note: We also use X to denote illegal states. For example, when two components try to put different values on the D bus, the conflicting bits on the D bus will become X.
8 The simulation model can be viewed in the Simulation view:
9 Each rectangle represents a component. Zooming in a component reveals its inner structure (if it has one).
10 The colored lines connecting these rectangles represent wires.
11 (Multiple-bit wires are displayed thicker than the single-bit wires, and always are black.
12 For single-bit wires, the color represents their current value: