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| -rw-r--r-- | decoders/timing/__init__.py | 25 | ||||
| -rw-r--r-- | decoders/timing/pd.py | 94 |
2 files changed, 119 insertions, 0 deletions
diff --git a/decoders/timing/__init__.py b/decoders/timing/__init__.py new file mode 100644 index 0000000..ee31509 --- /dev/null +++ b/decoders/timing/__init__.py @@ -0,0 +1,25 @@ +## +## This file is part of the libsigrokdecode project. +## +## Copyright (C) 2014 Torsten Duwe <duwe@suse.de> +## +## This program is free software; you can redistribute it and/or modify +## it under the terms of the GNU General Public License as published by +## the Free Software Foundation; either version 2 of the License, or +## (at your option) any later version. +## +## This program is distributed in the hope that it will be useful, +## but WITHOUT ANY WARRANTY; without even the implied warranty of +## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +## GNU General Public License for more details. +## +## You should have received a copy of the GNU General Public License +## along with this program; if not, write to the Free Software +## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +## + +''' +Timing decoder, find the time between edges. +''' + +from .pd import Decoder diff --git a/decoders/timing/pd.py b/decoders/timing/pd.py new file mode 100644 index 0000000..5cb162f --- /dev/null +++ b/decoders/timing/pd.py @@ -0,0 +1,94 @@ +## +## This file is part of the libsigrokdecode project. +## +## Copyright (C) 2014 Torsten Duwe <duwe@suse.de> +## Copyright (C) 2014 Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com> +## +## This program is free software; you can redistribute it and/or modify +## it under the terms of the GNU General Public License as published by +## the Free Software Foundation; either version 2 of the License, or +## (at your option) any later version. +## +## This program is distributed in the hope that it will be useful, +## but WITHOUT ANY WARRANTY; without even the implied warranty of +## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +## GNU General Public License for more details. +## +## You should have received a copy of the GNU General Public License +## along with this program; if not, write to the Free Software +## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +## + +import sigrokdecode as srd + +class SamplerateError(Exception): + pass + +def normalize_time(t): + if t >= 1.0: + return '%.3f sec' % t + elif t >= 0.001: + return '%.3f msec' % (t * 1000.0) + elif t >= 0.000001: + return '%.3f usec' % (t * 1000.0 * 1000.0) + elif t >= 0.000000001: + return '%.3f nsec' % (t * 1000.0 * 1000.0 * 1000.0) + else: + return '%f' % t + +class Decoder(srd.Decoder): + api_version = 2 + id = 'timing' + name = 'Timing' + longname = 'Timing calculation' + desc = 'Calculate time between edges.' + license = 'gplv2+' + inputs = ['logic'] + outputs = ['timing'] + channels = ( + {'id': 'data', 'name': 'Data', 'desc': 'Data line'}, + ) + annotations = ( + ('time', 'Time'), + ) + annotation_rows = ( + ('time', 'Time', (0,)), + ) + + def __init__(self, **kwargs): + self.samplerate = None + self.oldpin = None + self.last_samplenum = None + + def metadata(self, key, value): + if key == srd.SRD_CONF_SAMPLERATE: + self.samplerate = value + + def start(self): + self.out_ann = self.register(srd.OUTPUT_ANN) + + def decode(self, ss, es, data): + if not self.samplerate: + raise SamplerateError('Cannot decode without samplerate.') + + for (samplenum, (pin,)) in data: + # Ignore identical samples early on (for performance reasons). + if self.oldpin == pin: + continue + + if self.oldpin is None: + self.oldpin = pin + self.last_samplenum = samplenum + continue + + if self.oldpin != pin: + samples = samplenum - self.last_samplenum + t = samples / self.samplerate + + # Report the timing normalized. + self.put(self.last_samplenum, samplenum, self.out_ann, + [0, [normalize_time(t)]]) + + # Store data for next round. + self.last_samplenum = samplenum + self.oldpin = pin |