From 3c28d59cfc4ea2a52cdad90a0a2a3ea39e950ea9 Mon Sep 17 00:00:00 2001 From: jan Date: Thu, 31 Mar 2022 00:05:50 -0700 Subject: [PATCH] add readme --- README.md | 109 ++++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 106 insertions(+), 3 deletions(-) diff --git a/README.md b/README.md index fe1ee32..d860b6a 100644 --- a/README.md +++ b/README.md @@ -1,6 +1,109 @@ -snarl -===== +snarl README +============ Layout connectivity checker. -TODO: Documentation and examples! +`snarl` is a python package for checking electrical connectivity in multi-layer layouts. + +It is intended to be "poor-man's LVS" (layout-versus-schematic), for when poverty +has deprived the man of both a schematic and a better connectivity tool. + +- [Source repository](https://mpxd.net/code/jan/snarl) +- [PyPI](https://pypi.org/project/snarl) + +## Installation + +Requirements: +* python >= 3.9 (written and tested with 3.10) +* numpy +* pyclipper + + +Install with pip: +```bash +pip3 install snarl +``` + +Alternatively, install from git +```bash +pip3 install git+https://mpxd.net/code/jan/snarl.git@release + + +## Example +See `examples/check.py`. Note that the example uses `masque` to load data. + +```python3 +from pprint import pformat +from masque.file import gdsii, oasis +import snarl +import snarl.interfaces.masque + +# Layer definitions +connectivity = { + ((1, 0), (1, 2), (2, 0)), #M1 to M2 (via V12) + ((1, 0), (1, 3), (3, 0)), #M1 to M3 (via V13) + ((2, 0), (2, 3), (3, 0)), #M2 to M3 (via V23) + } + + +cells, props = oasis.readfile('connectivity.oas') +topcell = cells['top'] + +polys, labels = snarl.interfaces.masque.read_cell(topcell, connectivity) +nets_info = snarl.trace_connectivity(polys, labels, connectivity) + +print('\nFinal nets:') +print([kk for kk in nets_info.nets if isinstance(kk.name, str)]) + +print('\nShorted net sets:') +for short in nets_info.get_shorted_nets(): + print('(' + ','.join([repr(nn) for nn in sorted(list(short))]) + ')') + +print('\nOpen nets:') +print(pformat(dict(nets_info.get_open_nets()))) +``` + +this prints the following: + +``` +Nets ['SignalD', 'SignalI'] are shorted on layer (1, 0) in poly: + [[13000.0, -3000.0], + [16000.0, -3000.0], + [16000.0, -1000.0], + [13000.0, -1000.0], + [13000.0, 2000.0], + [12000.0, 2000.0], + [12000.0, -1000.0], + [11000.0, -1000.0], + [11000.0, -3000.0], + [12000.0, -3000.0], + [12000.0, -8000.0], + [13000.0, -8000.0]] +Nets ['SignalK', 'SignalK'] are shorted on layer (1, 0) in poly: + [[18500.0, -8500.0], [28200.0, -8500.0], [28200.0, 1000.0], [18500.0, 1000.0]] +Nets ['SignalC', 'SignalC'] are shorted on layer (1, 0) in poly: + [[10200.0, 0.0], [-1100.0, 0.0], [-1100.0, -1000.0], [10200.0, -1000.0]] +Nets ['SignalG', 'SignalH'] are shorted on layer (1, 0) in poly: + [[10100.0, -2000.0], [5100.0, -2000.0], [5100.0, -3000.0], [10100.0, -3000.0]] + +Final nets: +[SignalA, SignalC__0, SignalE, SignalG, SignalK__0, SignalK__2, SignalL] + +Shorted net sets: +(SignalC__0,SignalC__1,SignalD,SignalI) +(SignalK__0,SignalK__1) +(SignalG,SignalH) +(SignalA,SignalB) +(SignalE,SignalF) + +Open nets: +{'SignalK': [SignalK__0, SignalK__2]} +``` + +## Code organization + +The main functionality is in `trace_connectivity`. +Useful classes, namely `NetsInfo` and `NetName`, are in `snarl.tracker`. +`snarl.interfaces` contains helper code for interfacing with other packages. + +