User`s manual

Wave window
ModelSim Xilinx User’s Manual ModelSim XE Graphic Interface 7-177
In the illustration below, four data signals have been combined to form a new bus
called DATA1. Notice, the new bus has a value that is made up of the values of
its component signals arranged in a specific order. Virtual objects are indicated by
an orange diamond.
A group is simply a container for any number of signals. It has no value, and the
signals contained within it may be arranged in any order. In the illustration below,
the signals counter/count, counter/clk, and counter/reset have been combined in a
group called Counter. Notice that the Counter group has no value associated with
it. The counter, clk and reset signals may be arranged in any order.