net - format of .net files read/written by Magic's netlist editor
Netlist files are read and written by Magic's netlist editor in a very simple
ASCII format. The first line contains the characters `` Netlist
File'' (the leading blank is important). After that comes a blank line and
then the descriptions of one or more nets. Each net contains one or more
lines, where each line contains a single terminal name. The nets are separated
by blank lines. Any line that is blank or whose first character is blank is
considered to be a separator line and the rest of its contents are ignored.
Each terminal name is a path, much like a file path name in Unix. It consists of
one or more fields separated by slashes. The last field in the path is the
name of a label in a cell. The other fields (if any), are cell instance
identifiers that form a path from the edit cell down to the label. The first
instance identifier must name a subcell of the edit cell, the second must be a
subcell of the first, and so on.
Instance identifiers are unique within their parent cells, so a terminal path
selects a unique cell to contain the label. However, the same label may appear
multiple times within its cell. When this occurs, Magic assumes that the
identical labels identify electrically equivalent terminals; it will choose
the closest of them when routing to that terminal. Further, after connecting
to one of these terminals Magic may take advantage of the internal wiring
connecting them together and route through a cell to complete the net's
An example netlist file follows below. It contains three distinct nets.
This line starts with a blank, so it's a separator.