diff options
| -rw-r--r-- | decoders/stepper_motor/__init__.py | 26 | ||||
| -rw-r--r-- | decoders/stepper_motor/pd.py | 97 |
2 files changed, 123 insertions, 0 deletions
diff --git a/decoders/stepper_motor/__init__.py b/decoders/stepper_motor/__init__.py new file mode 100644 index 0000000..222d393 --- /dev/null +++ b/decoders/stepper_motor/__init__.py @@ -0,0 +1,26 @@ +## +## This file is part of the libsigrokdecode project. +## +## Copyright (C) 2015 Petteri Aimonen <jpa@sigrok.mail.kapsi.fi> +## +## 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 +## + +''' +This PD decodes the stepper motor controller signals (step / dir) and +shows the step speed and absolute position of the stepper motor. +''' + +from .pd import Decoder diff --git a/decoders/stepper_motor/pd.py b/decoders/stepper_motor/pd.py new file mode 100644 index 0000000..b3bb5bc --- /dev/null +++ b/decoders/stepper_motor/pd.py @@ -0,0 +1,97 @@ +## +## This file is part of the libsigrokdecode project. +## +## Copyright (C) 2015 Petteri Aimonen <jpa@sigrok.mail.kapsi.fi> +## +## 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 + +class Decoder(srd.Decoder): + api_version = 2 + id = 'stepper_motor' + name = 'Stepper motor' + longname = 'Stepper motor position / speed' + desc = 'Calculate absolute position and movement speed from step/dir signals.' + license = 'gplv2+' + inputs = ['logic'] + outputs = ['stepper_motor'] + channels = ( + {'id': 'step', 'name': 'Step', 'desc': 'Step pulse'}, + {'id': 'dir', 'name': 'Direction', 'desc': 'Direction select'}, + ) + options = ( + {'id': 'unit', 'desc': 'Unit', 'default': 'steps', + 'values': ('steps', 'mm')}, + {'id': 'steps_per_mm', 'desc': 'Steps per mm', 'default': 100.0}, + ) + annotations = ( + ('speed', 'Speed'), + ('position', 'Position') + ) + annotation_rows = ( + ('speed', 'Speed', (0,)), + ('position', 'Position', (1,)), + ) + + def __init__(self, **kwargs): + self.oldstep = None + self.prev_step_ss = None + self.pos = 0 + self.prev_speed = None + self.prev_pos = None + + def start(self): + self.out_ann = self.register(srd.OUTPUT_ANN) + + if self.options['unit'] == 'steps': + self.scale = 1 + self.format = '%0.0f' + self.unit = 'steps' + else: + self.scale = self.options['steps_per_mm'] + self.format = '%0.2f' + self.unit = 'mm' + + def step(self, ss, direction): + if self.prev_step_ss is not None: + delta = ss - self.prev_step_ss + speed = self.samplerate / delta / self.scale + speed_txt = self.format % speed + pos_txt = self.format % (self.pos / self.scale) + self.put(self.prev_step_ss, ss, self.out_ann, + [0, [speed_txt + ' ' + self.unit + '/s', speed_txt]]) + self.put(self.prev_step_ss, ss, self.out_ann, + [1, [pos_txt + ' ' + self.unit, pos_txt]]) + + self.pos += (1 if direction else -1) + self.prev_step_ss = ss + + def metadata(self, key, value): + if key == srd.SRD_CONF_SAMPLERATE: + self.samplerate = value + + def decode(self, ss, es, data): + if not self.samplerate: + raise SamplerateError('Cannot decode without samplerate.') + + for (self.samplenum, (step, direction)) in data: + if step == 1 and self.oldstep == 0: + self.step(self.samplenum, direction) + self.oldstep = step |