def open(self):
'''
Open connection with 5 retries.
'''
if self.mbSession is not None:
return
if self.address is None:
raise RuntimeError("Attempting to open connection to unknown address.")
if self.resMan is None:
self.resMan = pyvisa.ResourceManager()
try:
self.mbSession = self.resMan.open_resource(self.address)
self.mbSession.write_termination = self.termination
if not self.tempSess:
logger.debug('Opened %s', self.address)
except pyvisa.VisaIOError as err:
logger.warning('There was a problem opening the VISA %s... Error code: %s',
self.address, err.error_code)
if self._open_retries < OPEN_RETRIES:
self._open_retries += 1
time.sleep(0.5 * self._open_retries)
logger.warning('Trying again... (try = %s/%s)', self._open_retries, OPEN_RETRIES)
self.open()
else:
logger.error(err)
raise
else:
if self._open_retries != 0:
logger.warning('Found it!')
self._open_retries = 0
def amplAndOffs(self, amplOffs=None):
''' Amplitude and offset setting/getting
Only uses the data-bar because the other one is broken
Args:
amplOffs (tuple(float)): new amplitude and offset in volts
If either is None, returns but does not set
Returns:
(tuple(float)): amplitude and offset, read from hardware if specified as None
'''
if amplOffs is None:
amplOffs = (None, None)
if np.isscalar(amplOffs):
raise ValueError('amplOffs must be a tuple. ' +
'You can specify one element as None if you don\'t want to set it')
amplitude, offset = amplOffs
amplitude = np.clip(amplitude, *self.amplitudeRange)
if amplitude is not None:
self.setConfigParam('AMP', '{} V'.format(amplitude))
try:
ampl = float(self.getConfigParam('AMP').split(' ')[0])
except VisaIOError:
logger.error('unable to get the amplitude')
ampl = None
if offset is not None:
self.setConfigParam('OFS', '{} V'.format(offset))
try:
offs = float(self.getConfigParam('OFS').split(' ')[0])
except VisaIOError:
logger.error('unable to get the offset')
offs = None
return (ampl, offs)
def connect(self):
''' Connects to the socket and leaves the connection open.
If already connected, does nothing.
Returns:
socket object.
'''
if self._socket is None:
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM,
socket.IPPROTO_TCP)
try:
logger.debug("Attempting new connection (timeout = %s)",
str(self.timeout))
init_time = time.time()
s.settimeout(self.timeout)
s.connect((self.ip_address, self.port))
except socket.error:
# avoiding shutdown to prevent sending any data to remote socket
# https://stackoverflow.com/questions/13109899/does-socket-become-unusable-after-connect-fails
# s.shutdown(socket.SHUT_WR)
s.close()
del s
logger.error('Cannot connect to resource.')
raise
else:
final_time = time.time()
elapsed_time_ms = 1e3 * (final_time - init_time)
logger.debug("Connected. Time elapsed: %s msec",
'{:.2f}'.format(elapsed_time_ms))
self._socket = s
return self._socket
else:
return self._socket
def __transferData(self, chan):
''' Returns the raw data pulled from the scope as time (seconds) and voltage (Volts)
Args:
chan (int): one channel at a time
Returns:
:mod:`data.Waveform`: a time, voltage paired signal
Todo:
Make this binary transfer to go even faster
'''
chStr = 'CH' + str(chan)
self.setConfigParam('DATA:ENCDG', 'ASCII')
self.setConfigParam('DATA:SOURCE', chStr)
self.open()
try:
voltRaw = self.mbSession.query_ascii_values('CURV?')
except pyvisa.VisaIOError as err:
logger.error('Problem during query_ascii_values(\'CURV?\')')
try:
self.close()
except pyvisa.VisaIOError:
logger.error('Failed to close! %s', self.address)
raise err
self.close()
return voltRaw
def close(self):
if self.mbSession is None:
return
try:
self.mbSession.close()
except pyvisa.VisaIOError:
logger.error('There was a problem closing the VISA %s', self.address)
raise
self.mbSession = None
if not self.tempSess:
logger.debug('Closed %s', self.address)
def instrID(self):
"""Overloads the super function because the OSA does not respond to *IDN?
Instead sends a simple command and waits for a confirmed return
"""
try:
self.write('SPSWPMSK?')
except socket.error:
logger.error('OSA communication test failed. Sent: \'SPSWPMSK?\'')
raise
else:
return 'Apex AP2440A'
def write(self, writeStr):
try:
self.open()
try:
self.mbSession.write(writeStr)
except Exception:
logger.error('Problem writing to %s', self.address)
raise
logger.debug('%s - W - %s', self.address, writeStr)
finally:
if self.tempSess:
self.close()
def __getFullHardwareConfig(self, subgroup=''):
''' Get everything that is returned by the SET? query
Args:
subgroup (str): default '' means everything
Returns:
TekConfig: structured configuration object
'''
self.initHardware()
logger.info('Querying SET? response of %s', self.instrID())
try:
resp = self.query('SET?')
return TekConfig.fromSETresponse(resp, subgroup=subgroup)
except VisaIOError as err: # SET timed out. You are done.
logger.error(
'%s timed out on \'SET?\'. \
Try resetting with \'*RST\'.', self.instrID())
raise err
def query(self, queryStr, withTimeout=None):
retStr = None
try:
self.open()
logger.debug('%s - Q - %s', self.address, queryStr)
toutOrig = self.timeout
try:
if withTimeout is not None:
self.timeout = withTimeout
retStr = self.mbSession.query(queryStr)
if withTimeout is not None:
self.timeout = toutOrig
except Exception:
logger.error('Problem querying to %s', self.address)
# self.close()
raise
retStr = retStr.rstrip()
logger.debug('Query Read - %s', retStr)
finally:
if self.tempSess:
self.close()
return retStr
def _getHardwareConfig(self, cStrList):
''' Queries all or a subgroup of commands using the state of the 'live' config.
This does not return, but it puts it in the config['live'] attribute
Args:
cStrList (list or str): list of command strings. Can also be a scalar string
'''
self.initHardware()
if type(cStrList) is not list and type(cStrList) is str:
cStrList = [cStrList]
for cStr in cStrList:
if cStr[-1] == '&': # handle the sibling subdir token
cStr = cStr[:-2]
try:
ret = self.query(cStr + '?')
except VisaIOError:
logger.error(
'Problematic parameter was %s.\n'
'Likely it does not exist in this instrument command structure.',
cStr)
raise
logger.debug('Queried %s, got %s', cStr, ret)
if self.header:
val = ret.split(' ')[-1]
else:
val = ret
# Type detection
try:
val = float(val)
except ValueError:
pass
else:
if val == floor(val):
val = int(val)
self.config['live'].set(cStr, val)
