Naming Hardware Components, Microinstructions
and Machine Instructions
All hardware components, microinstructions, and machine instructions must be given names. You can name them anything you wish under the following conditions.
You must use at least one non-space character and you have different names for each unit of the same type.
Machine instruction names must be valid symbols in the assembly language syntax, which means they must consist of one or more letters or digits or belong to a set of punctuation characters specified by the user (in the Preferences dialog) and they must not start with a digit or a plus or minus sign followed by a digit. Only ASCII characters are allowed in machine instruction names.
It is strongly recommended, but not required, that all units of all types have unique names.
Note that if you give a register array of length 4 the name "A", then the 4 registers in the array will automatically be given the names "A[0]", "A[1]", "A[2]", "A[3]".