def test_command(subdevice, num_tests=2):
"""Adjust a command as necessary to get valid arguments.
"""
_LOG.info('command before testing:\n{}'.format(subdevice.cmd))
for i in range(2):
rc = subdevice.command_test()
if rc is None:
_LOG.info('command is valid')
return
_LOG.info('test {} returned {}\n{}'.format(i, rc, subdevice.cmd))
_LOG.error('error preparing command: {}'.format(rc))
_sys.exit(1)
def run(filename, subdevice, channel, range, aref, num_scans):
"""
>>> t1,data,t2 = run(filename='/dev/comedi0', subdevice=None,
... channel=0, range=0, aref=_constant.AREF.ground, num_scans=10)
>>> t1 # doctest: +SKIP
1332242184.029691
>>> t2 # doctest: +SKIP
1332242184.3311629
>>> data # doctest: +ELLIPSIS
array([...], dtype=uint32)
>>> data.shape
(10,)
"""
_LOG.info(
('measuring device={} subdevice={} channel={} range={} '
'analog-reference={} num-scans={}').format(filename, subdevice,
channel, range, aref,
num_scans))
device = _Device(filename=filename)
device.open()
try:
if subdevice is None:
subdevice = device.find_subdevice_by_type(
_constant.SUBDEVICE_TYPE.ai)
else:
subdevice = device.subdevice(subdevice)
insns = [subdevice.insn(), subdevice.insn(), subdevice.insn()]
insns[0].insn = insns[2].insn = _constant.INSN.gtod
insns[0].data = insns[2].data = [0, 0]
insns[1].insn = _constant.INSN.read
insns[1].data = [0] * num_scans
insns[1].chanspec = _ChanSpec(chan=channel, range=range, aref=aref)
device.do_insnlist(insns)
finally:
device.close()
t1 = insns[0].data[0] + insns[1].data[1] / 1e6
t2 = insns[2].data[0] + insns[2].data[1] / 1e6
return (t1, insns[1].data, t2)
def __init__(self, stream, subdevice, channels, physical=False,
plot=False):
self.stream = stream
self.subdevice = subdevice
self.channels = channels
self.physical = physical
self.plot = plot
if plot:
if _pyplot is None:
raise _matplotlib_import_error
self.figure = _pyplot.figure()
self.axes = self.figure.add_subplot(1, 1, 1)
self.n = 100
self.index = 0
self.tdata = _numpy.arange(self.n)
self.ydata = _numpy.zeros(
(2*self.n, len(channels)), dtype=_numpy.float32)
self.lines = []
for i,channel in enumerate(channels):
self.lines.append(_Line2D(
self.tdata, self.ydata[:self.n,i],
linestyle='', color='red', marker='.'))
self.axes.add_line(self.lines[-1])
self.axes.set_xlim(0, self.n-1)
self.axes.set_ylim(0, max(c.get_maxdata() for c in channels))
_pyplot.draw()
_LOG.debug('data writer initialized')
_LOG.debug('poll: {}'.format(self.subdevice.poll()))
_LOG.debug('get_buffer contents: {}'.format(
self.subdevice.get_buffer_contents()))
def run(filename, subdevice, channel, range, aref, num_scans):
"""
>>> t1,data,t2 = run(filename='/dev/comedi0', subdevice=None,
... channel=0, range=0, aref=_constant.AREF.ground, num_scans=10)
>>> t1 # doctest: +SKIP
1332242184.029691
>>> t2 # doctest: +SKIP
1332242184.3311629
>>> data # doctest: +ELLIPSIS
array([...], dtype=uint32)
>>> data.shape
(10,)
"""
_LOG.info(
("measuring device={} subdevice={} channel={} range={} " "analog-reference={} num-scans={}").format(
filename, subdevice, channel, range, aref, num_scans
)
)
device = _Device(filename=filename)
device.open()
try:
if subdevice is None:
subdevice = device.find_subdevice_by_type(_constant.SUBDEVICE_TYPE.ai)
else:
subdevice = device.subdevice(subdevice)
insns = [subdevice.insn(), subdevice.insn(), subdevice.insn()]
insns[0].insn = insns[2].insn = _constant.INSN.gtod
insns[0].data = insns[2].data = [0, 0]
insns[1].insn = _constant.INSN.read
insns[1].data = [0] * num_scans
insns[1].chanspec = _ChanSpec(chan=channel, range=range, aref=aref)
device.do_insnlist(insns)
finally:
device.close()
t1 = insns[0].data[0] + insns[1].data[1] / 1e6
t2 = insns[2].data[0] + insns[2].data[1] / 1e6
return (t1, insns[1].data, t2)
def __call__(self, data):
_LOG.debug('new data: {}'.format(data))
d = _numpy.ndarray(shape=(1,data.size), dtype=data.dtype, buffer=data)
if self.plot:
self.ydata[self.index,:] = d
self.ydata[self.index + self.n,:] = d
for i,line in enumerate(self.lines):
line.set_data(
self.tdata,
self.ydata[self.index+1:self.index + self.n+1,i])
_pyplot.draw()
self.index = (self.index + 1) % len(self.tdata)
write_data(
stream=self.stream, channels=self.channels, data=d,
physical=self.physical)
_LOG.debug('poll: {}'.format(self.subdevice.poll()))
_LOG.debug('get_buffer contents: {}'.format(
self.subdevice.get_buffer_contents()))
def read(device, subdevice=None, channels=[0], range=0, aref=0, period=0,
num_scans=2, reader=_utility.Reader, physical=False, plot=False,
stream=_sys.stdout):
"""Read ``num_scans`` samples from each specified channel.
"""
subdevice,channels = open_channels(
device=device, subdevice=subdevice, channels=channels, range=range,
aref=aref)
subdevice.cmd = prepare_command(
subdevice=subdevice, channels=channels, period=period,
num_scans=num_scans)
rc = test_command(subdevice=subdevice)
kwargs = {}
if reader == _utility.CallbackReader:
read_buffer_shape = (len(channels),)
kwargs = {
'callback': DataWriter(
stream=stream, subdevice=subdevice, channels=channels,
physical=physical, plot=plot),
'count': num_scans,
}
else:
read_buffer_shape = (num_scans, len(channels))
read_buffer = _numpy.zeros(read_buffer_shape, dtype=subdevice.get_dtype())
reader = reader(
subdevice=subdevice, buffer=read_buffer, name='Reader', **kwargs)
start = _time.time()
_LOG.info('start time: {}'.format(start))
subdevice.command()
reader.start()
while subdevice.get_flags().running:
_LOG.debug('running...')
_LOG.debug('poll: {}'.format(subdevice.poll()))
_LOG.debug('get_buffer offset: {}'.format(
subdevice.get_buffer_offset()))
_LOG.debug('get_buffer contents: {}'.format(
subdevice.get_buffer_contents()))
_time.sleep(0.5)
_LOG.debug('stopped running. joining reader...')
stop = _time.time()
_LOG.info('stop time: {}'.format(stop))
reader.join()
join = _time.time()
_LOG.info('join time: {}'.format(join))
_LOG.debug('poll: {}'.format(subdevice.poll()))
_LOG.debug('get_buffer offset: {}'.format(
subdevice.get_buffer_offset()))
_LOG.debug('get_buffer contents: {}'.format(
subdevice.get_buffer_contents()))
_LOG.info('stop delay: {}'.format(stop - start))
_LOG.info('join delay: {}'.format(join - stop))
if not isinstance(reader, _utility.CallbackReader):
write_data(
stream=stream, channels=channels, data=read_buffer,
physical=physical)
read(device=device, **kwargs)
finally:
device.close()
if __name__ == '__main__':
import pycomedi_demo_args
args = pycomedi_demo_args.parse_args(
description=__doc__,
argnames=['filename', 'subdevice', 'channels', 'aref', 'range',
'num-scans', 'mmap', 'callback', 'frequency', 'physical',
'plot', 'verbose'])
_LOG.info(('measuring device={0.filename} subdevice={0.subdevice} '
'channels={0.channels} range={0.range} '
'analog-reference={0.aref}'
).format(args))
if args.callback:
reader = _utility.CallbackReader
elif args.mmap:
reader = _utility.MMapReader
else:
reader = _utility.Reader
if args.plot:
if _pyplot is None:
raise _matplotlib_import_error
_pyplot.ion()
run(filename=args.filename, subdevice=args.subdevice,
channels=args.channels, aref=args.aref, range=args.range,
def __call__(self, parser, namespace, values, option_string=None):
level = _LOG.level
level -= 10 # e.g. logging.INFO -> logging.DEBUG
if level >= _logging.DEBUG:
_LOG.setLevel(level)
def display(t1, data, t2):
_LOG.info("initial time: {}".format(t1))
_LOG.info("final time: {}".format(t2))
_LOG.info("difference: {}".format(t2 - t1))
for x in insns[1].data:
print(x)
def display(t1, data, t2):
_LOG.info('initial time: {}'.format(t1))
_LOG.info('final time: {}'.format(t2))
_LOG.info('difference: {}'.format(t2 - t1))
for x in insns[1].data:
print(x)
def __call__(self, parser, namespace, values, option_string=None):
level = _LOG.level
level -= 10 # e.g. logging.INFO -> logging.DEBUG
if level >= _logging.DEBUG:
_LOG.setLevel(level)
