1NET(5) File Formats Manual NET(5)
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6 net - format of .net files read/written by Magic's netlist editor
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10 Netlist files are read and written by Magic's netlist editor in a very
11 simple ASCII format. The first line contains the characters
12 `` Netlist File'' (the leading blank is important). After that comes
13 a blank line and then the descriptions of one or more nets. Each net
14 contains one or more lines, where each line contains a single terminal
15 name. The nets are separated by blank lines. Any line that is blank
16 or whose first character is blank is considered to be a separator line
17 and the rest of its contents are ignored.
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19 Each terminal name is a path, much like a file path name in Unix. It
20 consists of one or more fields separated by slashes. The last field in
21 the path is the name of a label in a cell. The other fields (if any),
22 are cell instance identifiers that form a path from the edit cell down
23 to the label. The first instance identifier must name a subcell of the
24 edit cell, the second must be a subcell of the first, and so on.
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26 Instance identifiers are unique within their parent cells, so a termi‐
27 nal path selects a unique cell to contain the label. However, the same
28 label may appear multiple times within its cell. When this occurs,
29 Magic assumes that the identical labels identify electrically equiva‐
30 lent terminals; it will choose the closest of them when routing to that
31 terminal. Further, after connecting to one of these terminals Magic
32 may take advantage of the internal wiring connecting them together and
33 route through a cell to complete the net's wiring.
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35 An example netlist file follows below. It contains three distinct
36 nets.
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38 ———————————————————————————————————————
39 Netlist File
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41 alu/bit_1/cout
42 alu/bit_2/cin
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45 regcell[21,2]/output
46 latch[2]/input
47 This line starts with a blank, so it's a separator.
48 opcode_pla/out6
49 shifter/drivers/shift2
50 ———————————————————————————————————————
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54 magic(1)
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584th Berkeley Distribution NET(5)