the assumption of case insensitivity (e.g., VSS, Vss, and vss)
are kept separate even when writing SPICE netlists, which are
case insensitive. The code fix both avoids flagging these ports
when running ext2spice, and more importantly, allows the use of
"ext2spice short" without these ports ending up separate in the
output netlist.
to be declared for each device model, so that different models can
be specified for different parameter ranges. For example, this
will simplify the definition of the high-sheet-rho poly resistors
and the bipolar transistors in sky130 by removing the need for ID
marker layers; it also allows the correct device model to be
extracted when reading data from GDS that does not contain the
extra (and not foundry-approved) ID markers.
nets to be avoided for running antenna gate and diffusion area
checks when doing "lef write", which is to check if the pin of
the net is flagged with use "power" or use "ground". This avoids
the need to use the (recently added) "lef nocheck" option (although
that still exists as an additional way to control which nets do and
do not get checked).
been broken ever since moving to the Tcl/Tk wrapped version. Added
some new features that allow background commands from the window
handling (like pointer tracking) to be omitted from the log file
via a suspend/resume function. Added a header file and a few
commands at the top of the log file that align the log file contents
with the screen and box state at the start of logging. This makes
a log file which can be "played back" by sourcing it from the magic
console prompt. Per request from Harald Pretl.
list for output, but that the code in ExtRegion.c does not sort a
region's label list to keep ports at the beginning of the list. So
any net with multiple labels may end up with a non-port label as
the name of the node, which eventually becomes the name of the port.
A quick fix keeps these lists sorted.
"drc printrules". Implemented a new "drc" command option called
"drc ignore", which can be used to suppress reporting of specific
rules, for both "drc why" and "drc find". This can help with
finding an error buried among a large number of other errors.
be output twice for scaled devices (such as diodes in the sky130
process). Above and beyond the typo, though, the implementation
of offsets is not very well thought out and needs to be revised.
For one, the +/- notation can be confused with signs in the
parameter expression; that is also fixed in this commit. But
there is currently no way to express both a scale and an offset
for a device parameter.
'+' and '-' in the same way that '*' is currently used for specifying
a parameter scaling. The combination of a scale and offset for the
same parameter has not (yet) been implemented.
with "extract do local" now being equivalent to "extract path .".
This allows extraction files to be put in a subdirectory and not
clog up the current working directory. Also: Fixed some behavior
around the use of "ext2spice -p <path>" so that it (1) works, and
(2) is compatible with the new "extract path". Since the ext2spice
and ext2sim commands are effectively independent of the primary
extraction, the "-p" option is needed to correspond to the use of
"extract path". Hopefully this is seen as only a minor inconvenience.
to create a list of net names to ignore for antenna gate and
diffusion area checks. This allows the nets not to have to be
selected in their entirity but selected by chunk only. This
reduces the time to write LEF on a large layout back to approximately
what it was before the change to include the hidden area from "-hide"
in the antenna area checks. Plus, it greatly reduces the time to
generate LEF for large layouts when not using the "-hide" option.
perimeter are not initialized, and if a terminal perimeter/area
calculation is missed (which is happening on devices with terminals
in planes other than the plane of the identifying type), then the
perimeter/area of a previously handled device will get output.
(2) Corrected an error with "flatten -inplace" in which the command
fails to deal with instance arrays.
NaN results for devices which are not FETs (specifically, devices
that are declared using "msubckt" but are not FETs, although there
may have been a related issue with non-FET devices not getting the
correct M count), due to the device having zero measured width or
length. NOTE: This may need more investigation. If a subcircuit
device's method of merging cannot be understood, then such devices
should never extract with "merge aggressive", and should always
merge conservatively if and only if all parameters match.
when reading .ext files with "equiv" statements in them. The
generation of "equiv" statements was expanded recently, making it
more likely for this issue to show up. There may be devices in
a file that have a terminal node pointing to the node that gets
removed, and these must be updated to point to the node that
remains after merging. This requires a full loop over all
devices and so could have a potentially large impact; but in
general there are not many equiv statements (implying multiple
different labels attached to the same node) and so it is unlikely
that there would be a noticeable performance hit in practice.
gate and diffusion area on each pin is done before erasing parts
of the cell that are to be hidden by obstruction layers. That
preserves the antenna information even when "-hide" is used. This
corrects the issue raised by Kareem Farid in the github issue
tracker #236.
"space" is considered part of the substrate, then the check for
planes to search should exclude "space" from the type mask
first. Otherwise, all planes get searched, not just the substrate.
Also: The same routine can falsely flag a device terminal as
substrate if a split tile is marked as the device's region. This
was also fixed.
previous behavior that had inadvertently been changed. In recent
versions, "load <absolute_path> -dereference" would incorrectly
apply the dereferencing to <absolute_path> rather than just its
subcells. Cleaned up the code around DBCellRead() in the process,
so everything is more straightforward (although probably more
could be done in that regard).
of the cell. This will greatly help in diagnosing issues when
reading cells from multiple locations including cwd, relative
paths, PDK libraries, and the search path. Also: Reworked
the timestamp update message so that it prints all at once at
the end of processing, not printing output for every cell
processed as it is being processed. That prevents output from
the file read routine from getting interleaved with the
timestamp processing output.
labels that are not connected to their declared layers. It's the
latter type that need additional processing in ExtSubtree.
Limiting this processing significantly cuts down on processing
time when there are many labels in a layout, as happens with the
"def read -labels" command option.
can result in negative resistors due to integer overflow. In all
cases, the target was floating-point and it was only necessary to
recast everything to float first.
causing the SI suffix not to be the expected one. Adjusted the
bounds where each SI suffix is used to keep output in the range of
0.1 to 100, although the boundary is very subjective. Made a
correction to the extresist code to scan through all device records
for a tile type. However, (1) there are cases being missed, and (2)
this should not be necessary since all device types should be able
to be known exactly from the contents of the .sim file. Needs more
work.
window in the toolkit, which was to the "tkwait" command, which
waits for a change in state. What was intended was to wait for
a change in state to visible only; once visible, the "tkwait"
command should not invoked or else the process will block.
to "safer" strncpy() calls to prevent string buffer overflow.
Also: Reimplemented the loop in the GDS write routine that counts
ports and then outputs them in order. It was possible to hang
magic for a long time by giving a port a very, very large index
number. The new implementation uses qsort() to sort the ports
by index, which is obviously much more efficient for the worst
case (and efficient enough for all normal cases).
dereferencing, and making the behavior of "load" on the command
line (i.e., loading a cell from a file) the same as the
behavior of loading a cell as a result of expanding an unloaded
instance. In both cases, if "load -dereference" is used, and
a cell does not exist in any search path but does exist in the
original location, without dereferencing, then the cell will be
loaded from the original location. Also: Corrected an error
that has existed since adding the capability to read compressed
files, which causes magic to crash when attempting to run the
"crash recover" command (because that routine was mixing
compressed and regular file stream calls).
inside a halo area. The previous implementation used a linear
accounting of error to determine the amount of shielding, but
since the shielding is nonlinear, this is a poor approximation
and regularly overestimates the shielding and leads to negative
capacitances. The corrected method makes many more calls to
the atan() function and the performance impact for extraction
will need to be evaluated.
ground node name (which is static) gets put on the node list and
is improperly deallocated. Corrected by simply allocating the
string for the default substrate node instead of using the static
string.
that aren't actually handled by the "lef write" command. The three
mentions are "LEFsource", "LEFuse", and "LEFshape", all of which
refer to names of pin properties, not macro properties. These
mentions were probably left over from early work.
(truly) missing a terminal (such as a MOSCAP made with a gate
extending into but not crossing a diffusion region). Added the
most requested GUI feature, which is a vertical scrollbar on the
parameterized device window (could be improved by maximizing
window height without exceeding display height).
222 from Sean Cross. Corrected a few places where the blanket
conversion "Region"->"ExtRegion" picked up some comment lines
that were unrelated to the structure name.
the cell being reworked for port numbering. Otherwise *all*
labels are selected, which can take a very long time depending on
how many labels are in the layout. Note: Need a "select area
ports" function, and better yet, rework the whole label database
so that magic no longer has to run compute-intensive routines
like DBEraseLabelsByContent().
"cif *hier write disable" and "cif *array write disable" commands
for a specific cell def and its descendents. The revision ensures
that all descendents apply the override. The "cif write" command
uses a stack instead of recursion, which makes it difficult to
apply the same method. Currently the method only works for the
"gds write" command, and implementing the feature for "cif write"
is deemed not worth the effort.
the "connected other node to. . ." message when terminals of a
device are shorted. A long enough node name, especially one
created by concatenating hierarchy when flattening a cell, can
easily overrun the short 256-byte string buffer. Fixed by
changing strcat() to strncat().
natural sort instead of ASCII-based sorting, so that ports that
are numbered arrays will be indexed properly by count. Also:
Modified the "extresist" handling of substrate to draw the default
substrate type over the entire cell area (less areas of nwell or
other conflicting type). This allows extresist to extract the
entire substrate as a resistive network. The result is ugly and
may warrant some aggressive network simplification, but it should
at least be realistic.
2-terminal devices without complaining. The previous handling
seemed to be technically correct other than spitting out warnings
about missing terminals.
tech file "extract" section to work correctly when the offset is
negative. Generally, a negative offset is nonphysical and is just
curve-fitting round-off error, but the existing code was failing
to divide out the factor of 1000 that had been multiplied through
when reading the tech file, resulting in a very wrong offset.
when internal units no longer match lambda units. The text
would match the dimension of the cursor box, but the measurement
lines would be drawn assuming a lambda scale, not the internal
scale.
isolate the terminal areas of a device (e.g., source and drain)
and calculate their area and perimeter individually for the
device (in addition to the traditional method of calculating
area and perimeter of each resistance class for the entire node).
Also: Reworked the SPICE syntax output to generate SI values
in the range 1-1000 with the appropriate suffix (e.g., "20u")
instead of defaulting to "u" for lengths and "p" for areas.
This prevents it from producing weird units like "150000u" when
a process definition already includes a scalefactor.
Reworked the "extresist" code to use the device terminal area
and perimeter. This fixes an error in which "extresist" would
lose these values and "ext2spice" with option "extresist on"
would generate a new netlist output with zero terminal areas
and perimeters.
transistor records match between the ".ext" file and the ".res.ext"
file for the number of terminals per device. Previously, the first
device type for the layer type was always being used, and if it had
fewer terminals (e.g., a MOScap), then one terminal would go missing
in the output.
This is diagnostic only and does not change the read-in
behavior.
(2) ext2spice: Corrected an error that had been introduced
into version 8.3.171 that accidentally marks all devices
as visited which causes all source/drain areas and
perimeters to be output as zero.
(3) extract: Sweeping changes to handling of fringe
capacitance. Removed the (recently added) "fringeshieldhalo"
parameter from the tech file. Reworked the fringe
capacitance models based on results from the "capiche"
project (github/RTimothyEdwards/capiche). Fringe shielding
is now done by clipping fringe at the boundary of a
shielding shape, rather than trying to calculate the
amount of shielding (as the "capiche" project proved this
to be equivalent). Values for partial fringing are modeled
by atan(x), which like the sidewall (1/x) curve, extends to
infinity and values are limited by the halo but do not
otherwise depend on the halo. Because of this, the halo can
be made variable and controlled by the user for deciding on
the tradeoff between accuracy and run time. A new command
option "extract halo" was added to allow this control over
the halo distance.
three types: "none", "temporary", and "keep" (instead of "true"
or "false"). "none" now reverts back to the original behavior,
because it was found that saving polygons in subcells prevents
them from participating in boolean operations. The "keep"
option is the original option (polygons kept in subcells), and
"temporary" is the one recently introduced (which puts polygons
in subcells and then flattens them). This restores the original
method while retaining the recently implemented method. However,
a proper solution needs to be found that deals with the problem
of boolean operators.
Tim Edwards