2 ## This file is part of the libsigrokdecode project.
4 ## Copyright (C) 2015 Petteri Aimonen <jpa@sigrok.mail.kapsi.fi>
6 ## This program is free software; you can redistribute it and/or modify
7 ## it under the terms of the GNU General Public License as published by
8 ## the Free Software Foundation; either version 2 of the License, or
9 ## (at your option) any later version.
11 ## This program is distributed in the hope that it will be useful,
12 ## but WITHOUT ANY WARRANTY; without even the implied warranty of
13 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 ## GNU General Public License for more details.
16 ## You should have received a copy of the GNU General Public License
17 ## along with this program; if not, write to the Free Software
18 ## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 import sigrokdecode as srd
23 class SamplerateError(Exception):
26 class Decoder(srd.Decoder):
29 name = 'Stepper motor'
30 longname = 'Stepper motor position / speed'
31 desc = 'Absolute position and movement speed from step/dir.'
34 outputs = ['stepper_motor']
36 {'id': 'step', 'name': 'Step', 'desc': 'Step pulse'},
37 {'id': 'dir', 'name': 'Direction', 'desc': 'Direction select'},
40 {'id': 'unit', 'desc': 'Unit', 'default': 'steps',
41 'values': ('steps', 'mm')},
42 {'id': 'steps_per_mm', 'desc': 'Steps per mm', 'default': 100.0},
46 ('position', 'Position')
49 ('speed', 'Speed', (0,)),
50 ('position', 'Position', (1,)),
55 self.ss_prev_step = None
57 self.prev_speed = None
61 self.out_ann = self.register(srd.OUTPUT_ANN)
63 if self.options['unit'] == 'steps':
68 self.scale = self.options['steps_per_mm']
72 def step(self, ss, direction):
73 if self.ss_prev_step is not None:
74 delta = ss - self.ss_prev_step
75 speed = self.samplerate / delta / self.scale
76 speed_txt = self.format % speed
77 pos_txt = self.format % (self.pos / self.scale)
78 self.put(self.ss_prev_step, ss, self.out_ann,
79 [0, [speed_txt + ' ' + self.unit + '/s', speed_txt]])
80 self.put(self.ss_prev_step, ss, self.out_ann,
81 [1, [pos_txt + ' ' + self.unit, pos_txt]])
83 self.pos += (1 if direction else -1)
84 self.ss_prev_step = ss
86 def metadata(self, key, value):
87 if key == srd.SRD_CONF_SAMPLERATE:
88 self.samplerate = value
90 def decode(self, ss, es, data):
91 if not self.samplerate:
92 raise SamplerateError('Cannot decode without samplerate.')
94 for (self.samplenum, (step, direction)) in data:
95 if step == 1 and self.oldstep == 0:
96 self.step(self.samplenum, direction)