determining what does and doesn't get into the R-C extraction
output. Added option "debug" and moved all excess diagnostic
information to be gated by this flag. Corrected an issue in
the standard extraction in which the substrate is always output
with zero lumped resistance, preventing it from being checked
by "extresist" for inclusion or exclusion in the .res.ext output.
Reinstated the computation of minimum resistance transistor but
excluded other devices. Added more sane handling of exceptional
conditions like loops. The result is a more consistent check of
nets in the design. However, I still need to recheck the
"rg_maxres" calculation because it appears to be too low.
(1) An incorrect use of ExtResetTiles() was found in "extresist"
which impacts performance, especially for small nets.
(2) Corrected units for resistance tolerance in extresist, and
handled output printing in fs when delay values get below ps
size.
(3) Added command option "extract do unique notopports" to be the
extraction option equivalent of the standalone command
"extract unique notopports".
(4) Changed the "extresist" default for "mindelay" to 1ps from 0,
in response to the observation that lumped resistance from
"extract" can be an extreme overestimate, and the extracted
time delay from "extesist" calculations should be used as a
better determination of whether a net should be output as a
resistor network or not.
(5) Added documentation for both "extract do unique notopports"
and the change to the "extresist" default values.
that "extresist" selects or rejects networks for resistance
extraction. The "tolerance" value, which nobody (including
myself) seems to understand, is now deprecated, replaced by
a handful of more meaningful options: "threshold" to set a
lumped resistance estimate threshold to determined whether or
not to extract a network; "minres" to specify when to prune
small resistors from the resulting tree network, and "mindelay"
to gate the selection and output on the estimated signal
propagation delay. With these settings, I am much better able
to control the size and complexity of the resulting output.
The website documentation now points to these contents in a clone
of the repository on opencircuitdesign.com, so all future edits of
the command-line documentation will be made directly to the git
repository. Also: Changed the precision of box values printed in
microns from 2 to 3 digits after the decimal place, so that 5 nanometer
grids do not get values clipped in the output.
R. Timothy Edwards