1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
|
# Copyright 2015 ARM Limited
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
from __future__ import division
import os
import csv
import signal
import tempfile
import struct
import subprocess
from devlib.instrument import Instrument, CONTINUOUS, MeasurementsCsv
from devlib.exception import HostError
from devlib.utils.misc import which
class EnergyProbeInstrument(Instrument):
mode = CONTINUOUS
def __init__(self, target, resistor_values,
labels=None,
device_entry='/dev/ttyACM0',
):
super(EnergyProbeInstrument, self).__init__(target)
self.resistor_values = resistor_values
if labels is not None:
self.labels = labels
else:
self.labels = ['PORT_{}'.format(i)
for i in xrange(len(resistor_values))]
self.device_entry = device_entry
self.caiman = which('caiman')
if self.caiman is None:
raise HostError('caiman must be installed on the host '
'(see https://github.com/ARM-software/caiman)')
self.attributes_per_sample = 3
self.bytes_per_sample = self.attributes_per_sample * 4
self.attributes = ['power', 'voltage', 'current']
self.command = None
self.raw_output_directory = None
self.process = None
self.sample_rate_hz = 10000 # Determined empirically
self.raw_data_file = None
for label in self.labels:
for kind in self.attributes:
self.add_channel(label, kind)
def reset(self, sites=None, kinds=None, channels=None):
super(EnergyProbeInstrument, self).reset(sites, kinds, channels)
self.raw_output_directory = tempfile.mkdtemp(prefix='eprobe-caiman-')
parts = ['-r {}:{} '.format(i, int(1000 * rval))
for i, rval in enumerate(self.resistor_values)]
rstring = ''.join(parts)
self.command = '{} -d {} -l {} {}'.format(self.caiman, self.device_entry, rstring, self.raw_output_directory)
self.raw_data_file = None
def start(self):
self.logger.debug(self.command)
self.process = subprocess.Popen(self.command,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
stdin=subprocess.PIPE,
preexec_fn=os.setpgrp,
shell=True)
def stop(self):
self.process.poll()
if self.process.returncode is not None:
stdout, stderr = self.process.communicate()
raise HostError(
'Energy Probe: Caiman exited unexpectedly with exit code {}.\n'
'stdout:\n{}\nstderr:\n{}'.format(self.process.returncode,
stdout, stderr))
os.killpg(self.process.pid, signal.SIGINT)
def get_data(self, outfile): # pylint: disable=R0914
all_channels = [c.label for c in self.list_channels()]
active_channels = [c.label for c in self.active_channels]
active_indexes = [all_channels.index(ac) for ac in active_channels]
num_of_ports = len(self.resistor_values)
struct_format = '{}I'.format(num_of_ports * self.attributes_per_sample)
not_a_full_row_seen = False
self.raw_data_file = os.path.join(self.raw_output_directory, '0000000000')
self.logger.debug('Parsing raw data file: {}'.format(self.raw_data_file))
with open(self.raw_data_file, 'rb') as bfile:
with open(outfile, 'wb') as wfh:
writer = csv.writer(wfh)
writer.writerow(active_channels)
while True:
data = bfile.read(num_of_ports * self.bytes_per_sample)
if data == '':
break
try:
unpacked_data = struct.unpack(struct_format, data)
row = [unpacked_data[i] / 1000 for i in active_indexes]
writer.writerow(row)
except struct.error:
if not_a_full_row_seen:
self.logger.warn('possibly missaligned caiman raw data, row contained {} bytes'.format(len(data)))
continue
else:
not_a_full_row_seen = True
return MeasurementsCsv(outfile, self.active_channels, self.sample_rate_hz)
def get_raw(self):
return [self.raw_data_file]
|
