1EXTCHECK(1) General Commands Manual EXTCHECK(1)
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6 extcheck - check hierarchical ext(5) files for global node connectivity
7 and summarize number of fets, nodes, etc.
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10 extcheck [ -c cthresh ] [ -p path ] [ -r rthresh ] [ -s sym=value ] [
11 -C ] [ -R ] [ -S symfile ] [ -T tech ] root
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15 Extcheck will read an extracted circuit in the hierarchical ext(5) rep‐
16 resentation produced by Magic, check to ensure that all global nodes
17 (those to which a label ending in an exclamantion point is attached)
18 are fully connected in the layout, and then print a count of the number
19 of various items (nodes, fets, etc) encountered while flattening the
20 circuit. The root of the tree to be processed is the file root.ext; it
21 and all the files it references are recursively flattened.
22 The following options are recognized:
24 -c cthresh
26 Set the capacitance threshold to cthresh femtofarads. Extcheck
27 will count the number of explicit internodal capacitors greater
28 than cthresh, the number of nodes whose capacitance is greater
29 than cthresh, as well as the total number of nodes. (Other pro‐
30 grams such as ext2sim(1) use this option as a threshold value
31 below which a capacitor will not be output). The default value
32 for cthresh is 10 femtofarads.
33 -p path
35 Normally, the path to search for .ext files is determined by
36 looking for path commands in first ~cad/lib/magic/sys/.magic,
37 then ~/.magic, then .magic in the current directory. If -p is
38 specified, the colon-separated list of directories specified by
39 path is used instead. Each of these directories is searched in
40 turn for the .ext files in a design.
41 -r rthresh
43 Set the resistance threshold to rthresh ohms. Similar in func‐
44 tion to -c, but for resistances. The default value for rthresh
45 is 10 ohms.
46 -s sym=value
48 It's possible to use special attributes attached to transistor
49 gates to control the length and width of transistors explicitly,
50 rather than allowing them to be determined by the extractor.
51 These attributes are of the form ext:w=width^ or ext:l=length^,
52 where width or length can either be numeric, or textual. (The
53 trailing ``^'' indicates that these are transistor gate
54 attributes). If textual, they are treated as symbols which can
55 be assigned a numeric value at the time ext2sim is run. The -s
56 flag is used to assign numeric values to symbols. If a textual
57 symbol appears in one of the above attributes, but isn't given a
58 numeric value via -s (or -S below), then it is ignored; other‐
59 wise, the transistor's length or width is set to the numeric
60 value defined for that symbol. (This option is not currently
61 used by extcheck, but it is common to ext2sim(1) and other tools
62 that are written using the extflat(3) library)
63 -C Set the capacitance threshold to infinity. Because this avoids
65 any internodal capacitance processing, all tools will run faster
66 when this flag is given.
67 -R Set the resistance threshold to infinity.
69 -S symfile
71 Each line in the file symfile is of the form sym=value, just
72 like the argument to the -s flag above; the lines are inter‐
73 preted in the same fashion. (This option is not currently used
74 by extcheck, but it is common to ext2sim et. al.)
75 -T tech
77 Set the technology in the output .sim file to tech. This over‐
78 rides any technology specified in the root .ext file.
79
82 ext2dlys(1), ext2sim(1), ext2spice(1), magic(1), rsim(1), sim2spice(1),
83 ext(5), sim(5)
84
87 Walter Scott
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91 The -s mechanism is incomplete; it should allow quantities other than
92 transistor lengths and widths to be specified.
93 EXTCHECK(1)