Value Change Dump File (.vcd) Definition
A Value Change Dump File is an ASCII file which contains header information, variable definitions, and the value changes for specified variables, or all variables, in a given design. The value changes for a variable are given in scalar or vector format, based on the nature of the variable.
If you open a Value Change Dump File within a Quartus® Prime project, any scopes defined in the file do not appear as part of the signal name. However, if you open a Value Change Dump File independently in the Quartus® Prime graphical user interface, all defined scopes appear as part of signal names.