What is a watch window? How do I use it?
During the simulation, you can highlight multiple signals from the bottom window of Structures tab, right click and choose Add to Watch. The Watch window is a debugging tool designed to display values of selected objects (signals, variables, nets, registers, etc.) in the simulated model.
The window is divided into several columns:
The column has no title and is displayed as the leftmost. If an event has occurred on a signal in the current simulation cycle, it is symbolized by a red exclamation mark (!).
The identifier of the object.
The current value of the object. For files, the column shows the open kind information (read_mode, write_mode, append_mode) and the file name with the full path.
For VHDL, the type of the object. For Verilog, reg or the type of the net.
The previous value of the object, that is, the value of the object before the last event. This column is used only for signals (including ports).
Last Event Time
The time of the last event. This column is used only for signals (including ports).