]>
Commit | Line | Data |
---|---|---|
1 | ## | |
2 | ## This file is part of the sigrok-meter project. | |
3 | ## | |
4 | ## Copyright (C) 2013 Uwe Hermann <uwe@hermann-uwe.de> | |
5 | ## Copyright (C) 2014 Jens Steinhauser <jens.steinhauser@gmail.com> | |
6 | ## | |
7 | ## This program is free software; you can redistribute it and/or modify | |
8 | ## it under the terms of the GNU General Public License as published by | |
9 | ## the Free Software Foundation; either version 2 of the License, or | |
10 | ## (at your option) any later version. | |
11 | ## | |
12 | ## This program is distributed in the hope that it will be useful, | |
13 | ## but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | ## GNU General Public License for more details. | |
16 | ## | |
17 | ## You should have received a copy of the GNU General Public License | |
18 | ## along with this program; if not, write to the Free Software | |
19 | ## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
20 | ## | |
21 | ||
22 | import qtcompat | |
23 | import re | |
24 | import sigrok.core as sr | |
25 | ||
26 | QtCore = qtcompat.QtCore | |
27 | QtGui = qtcompat.QtGui | |
28 | ||
29 | class SamplingThread(QtCore.QObject): | |
30 | '''Class that handles the reception of sigrok packets in the background.''' | |
31 | ||
32 | class Worker(QtCore.QObject): | |
33 | '''Helper class that does the actual work in another thread.''' | |
34 | ||
35 | '''Signal emitted when new data arrived.''' | |
36 | measured = QtCore.Signal(object, object, object) | |
37 | ||
38 | '''Signal emmited in case of an error.''' | |
39 | error = QtCore.Signal(str) | |
40 | ||
41 | def __init__(self, context, drivers): | |
42 | super(self.__class__, self).__init__() | |
43 | ||
44 | self.context = context | |
45 | self.drivers = drivers | |
46 | ||
47 | self.sampling = False | |
48 | ||
49 | def parse_configstring(self, cs): | |
50 | '''Dissect a config string and return the options as a | |
51 | dictionary.''' | |
52 | ||
53 | def parse_option(k, v): | |
54 | '''Parse the value for a single option.''' | |
55 | try: | |
56 | ck = sr.ConfigKey.get_by_identifier(k) | |
57 | except: | |
58 | raise ValueError('No option named "{}".'.format(k)) | |
59 | ||
60 | try: | |
61 | val = ck.parse_string(v) | |
62 | except: | |
63 | raise ValueError( | |
64 | 'Invalid value "{}" for option "{}".'.format(v, k)) | |
65 | ||
66 | return (k, val) | |
67 | ||
68 | if not re.match('(([^:=]+=[^:=]+)(:[^:=]+=[^:=]+)*)?$', cs): | |
69 | raise ValueError( | |
70 | '"{}" is not a valid configuration string.'.format(cs)) | |
71 | ||
72 | if not cs: | |
73 | return {} | |
74 | ||
75 | opts = cs.split(':') | |
76 | opts = [tuple(kv.split('=')) for kv in opts] | |
77 | opts = [parse_option(k, v) for (k, v) in opts] | |
78 | return dict(opts) | |
79 | ||
80 | def parse_driverstring(self, ds): | |
81 | '''Dissect the driver string and return a tuple consisting of | |
82 | the driver name and the options (as a dictionary).''' | |
83 | ||
84 | m = re.match('(?P<name>[^:]+)(?P<opts>(:[^:=]+=[^:=]+)*)$', ds) | |
85 | if not m: | |
86 | raise ValueError('"{}" is not a valid driver string.'.format(ds)) | |
87 | ||
88 | opts = m.group('opts')[1:] | |
89 | return (m.group('name'), self.parse_configstring(opts)) | |
90 | ||
91 | @QtCore.Slot() | |
92 | def start_sampling(self): | |
93 | devices = [] | |
94 | for (ds, cs) in self.drivers: | |
95 | # Process driver string. | |
96 | try: | |
97 | (name, opts) = self.parse_driverstring(ds) | |
98 | if not name in self.context.drivers: | |
99 | raise RuntimeError('No driver named "{}".'.format(name)) | |
100 | ||
101 | driver = self.context.drivers[name] | |
102 | devs = driver.scan(**opts) | |
103 | if not devs: | |
104 | raise RuntimeError('No devices found.') | |
105 | ||
106 | device = devs[0] | |
107 | except Exception as e: | |
108 | self.error.emit( | |
109 | 'Error processing driver string:\n{}'.format(e)) | |
110 | return | |
111 | ||
112 | # Process configuration string. | |
113 | try: | |
114 | cfgs = self.parse_configstring(cs) | |
115 | for k, v in cfgs.items(): | |
116 | device.config_set(sr.ConfigKey.get_by_identifier(k), v) | |
117 | except Exception as e: | |
118 | self.error.emit( | |
119 | 'Error processing configuration string:\n{}'.format(e)) | |
120 | return | |
121 | ||
122 | devices.append(device) | |
123 | ||
124 | self.session = self.context.create_session() | |
125 | for dev in devices: | |
126 | self.session.add_device(dev) | |
127 | dev.open() | |
128 | self.session.add_datafeed_callback(self.callback) | |
129 | self.session.start() | |
130 | self.sampling = True | |
131 | self.session.run() | |
132 | ||
133 | # If sampling is 'True' here, it means that 'stop_sampling()' was | |
134 | # not called, therefore 'session.run()' ended too early, indicating | |
135 | # an error. | |
136 | if self.sampling: | |
137 | self.error.emit('An error occured during the acquisition.') | |
138 | ||
139 | def stop_sampling(self): | |
140 | if self.sampling: | |
141 | self.sampling = False | |
142 | self.session.stop() | |
143 | ||
144 | def callback(self, device, packet): | |
145 | if not sr: | |
146 | # In rare cases it can happen that the callback fires while | |
147 | # the interpreter is shutting down. Then the sigrok module | |
148 | # is already set to 'None'. | |
149 | return | |
150 | ||
151 | if packet.type != sr.PacketType.ANALOG: | |
152 | return | |
153 | ||
154 | if not len(packet.payload.channels): | |
155 | return | |
156 | ||
157 | # TODO: find a device with multiple channels in one packet | |
158 | channel = packet.payload.channels[0] | |
159 | ||
160 | # The most recent value. | |
161 | value = packet.payload.data[0][-1] | |
162 | ||
163 | self.measured.emit(device, channel, | |
164 | (value, packet.payload.unit, packet.payload.mq_flags)) | |
165 | ||
166 | # Signal used to start the worker across threads. | |
167 | _start_signal = QtCore.Signal() | |
168 | ||
169 | def __init__(self, context, drivers): | |
170 | super(self.__class__, self).__init__() | |
171 | ||
172 | self.worker = self.Worker(context, drivers) | |
173 | self.thread = QtCore.QThread() | |
174 | self.worker.moveToThread(self.thread) | |
175 | ||
176 | self._start_signal.connect(self.worker.start_sampling) | |
177 | ||
178 | # Expose the signals of the worker. | |
179 | self.measured = self.worker.measured | |
180 | self.error = self.worker.error | |
181 | ||
182 | self.thread.start() | |
183 | ||
184 | def start(self): | |
185 | '''Start sampling.''' | |
186 | self._start_signal.emit() | |
187 | ||
188 | def stop(self): | |
189 | '''Stop sampling and stop the background thread.''' | |
190 | self.worker.stop_sampling() | |
191 | self.thread.quit() | |
192 | self.thread.wait() |