def __set_stop_bits(self, bits):
deci_bits = 10 * bits
if 9 < deci_bits < 11: deci_bits = 10
elif 14 < deci_bits < 16: deci_bits = 15
elif 19 < deci_bits < 21: deci_bits = 20
else: raise ValueError, "invalid number of stop bits"
vpp43.set_attribute(self.vi, VI_ATTR_ASRL_STOP_BITS, deci_bits)
def __set_stop_bits(self, bits):
deci_bits = 10 * bits
if 9 < deci_bits < 11: deci_bits = 10
elif 14 < deci_bits < 16: deci_bits = 15
elif 19 < deci_bits < 21: deci_bits = 20
else: raise ValueError, "invalid number of stop bits"
vpp43.set_attribute(self.vi, VI_ATTR_ASRL_STOP_BITS, deci_bits)
def __init__(self, resource_name=None, **keyw):
"""ResourceTemplate class constructor. It opens a session to the
resource.
Parameters:
resource_name -- (optional) the VISA name for the resource,
e.g. "GPIB::10". If "None", it's assumed that the resource manager
is to be constructed.
keyw -- keyword argument for the class constructor of the device instance
to be generated. Allowed arguments: lock, timeout. See Instrument
class for a detailed description.
"""
_warn_for_invalid_keyword_arguments(keyw, ("lock", "timeout"))
if self.__class__ is ResourceTemplate:
raise TypeError("trying to instantiate an abstract class")
if resource_name is not None: # is none for the resource manager
warnings.filterwarnings("ignore", "VI_SUCCESS_DEV_NPRESENT")
self.vi = vpp43.open(resource_manager.session, resource_name,
keyw.get("lock", VI_NO_LOCK))
if vpp43.get_status() == VI_SUCCESS_DEV_NPRESENT:
# okay, the device was not ready when we opened the session.
# Now it gets five seconds more to become ready. Every 0.1
# seconds we probe it with viClear.
passed_time = 0 # in seconds
while passed_time < 5.0:
time.sleep(0.1)
passed_time += 0.1
try:
vpp43.clear(self.vi)
except VisaIOError as error:
if error.error_code == VI_ERROR_NLISTENERS:
continue
else:
raise
break
else:
# Very last chance, this time without exception handling
time.sleep(0.1)
passed_time += 0.1
vpp43.clear(self.vi)
_removefilter("ignore", "VI_SUCCESS_DEV_NPRESENT")
timeout = keyw.get("timeout", 5)
if timeout is None:
vpp43.set_attribute(self.vi, VI_ATTR_TMO_VALUE,
VI_TMO_INFINITE)
else:
self.timeout = timeout
def __init__(self, resource_name=None, **keyw):
"""ResourceTemplate class constructor. It opens a session to the
resource.
Parameters:
resource_name -- (optional) the VISA name for the resource,
e.g. "GPIB::10". If "None", it's assumed that the resource manager
is to be constructed.
keyw -- keyword argument for the class constructor of the device instance
to be generated. Allowed arguments: lock, timeout. See Instrument
class for a detailed description.
"""
_warn_for_invalid_keyword_arguments(keyw, ("lock", "timeout"))
if self.__class__ is ResourceTemplate:
raise TypeError, "trying to instantiate an abstract class"
if resource_name is not None: # is none for the resource manager
warnings.filterwarnings("ignore", "VI_SUCCESS_DEV_NPRESENT")
self.vi = vpp43.open(resource_manager.session, resource_name,
keyw.get("lock", VI_NO_LOCK))
if vpp43.get_status() == VI_SUCCESS_DEV_NPRESENT:
# okay, the device was not ready when we opened the session.
# Now it gets five seconds more to become ready. Every 0.1
# seconds we probe it with viClear.
passed_time = 0 # in seconds
while passed_time < 5.0:
time.sleep(0.1)
passed_time += 0.1
try:
vpp43.clear(self.vi)
except VisaIOError, error:
if error.error_code == VI_ERROR_NLISTENERS:
continue
else: raise
break
else:
# Very last chance, this time without exception handling
time.sleep(0.1)
passed_time += 0.1
vpp43.clear(self.vi)
_removefilter("ignore", "VI_SUCCESS_DEV_NPRESENT")
timeout = keyw.get("timeout", 5)
if timeout is None:
vpp43.set_attribute(self.vi, VI_ATTR_TMO_VALUE,
VI_TMO_INFINITE)
else:
self.timeout = timeout
def __init__(self, resource_name=None, **keyw):
_warn_for_invalid_keyword_arguments(keyw, ("lock", "timeout"))
if self.__class__ is ResourceTemplate:
raise TypeError("trying to instantiate an abstract class")
if resource_name is None: # is none for the resource manager
return
warnings.filterwarnings("ignore", "VI_SUCCESS_DEV_NPRESENT")
self.vi = vpp43.open(resource_manager.session, resource_name,
keyw.get("lock", VI_NO_LOCK))
if vpp43.get_status() == VI_SUCCESS_DEV_NPRESENT:
# okay, the device was not ready when we opened the session.
# Now it gets five seconds more to become ready. Every 0.1
# seconds we probe it with viClear.
passed_time = 0 # in seconds
while passed_time < 5.0:
time.sleep(0.1)
passed_time += 0.1
try:
vpp43.clear(self.vi)
except VisaIOError as error:
if error.error_code != VI_ERROR_NLISTENERS:
raise
break
else:
# Very last chance, this time without exception handling
time.sleep(0.1)
passed_time += 0.1
vpp43.clear(self.vi)
_removefilter("ignore", "VI_SUCCESS_DEV_NPRESENT")
timeout = keyw.get("timeout", 5)
if timeout is None:
vpp43.set_attribute(self.vi, VI_ATTR_TMO_VALUE, VI_TMO_INFINITE)
else:
self.timeout = timeout
def __set_term_chars(self, term_chars):
"""Set a new termination character sequence. See below the property
"term_char"."""
# First, reset termination characters, in case something bad happens.
self.__term_chars = ""
vpp43.set_attribute(self.vi, VI_ATTR_TERMCHAR_EN, VI_FALSE)
if term_chars == "" or term_chars == None:
self.__term_chars = term_chars
return
# Only the last character in term_chars is the real low-level
# termination character, the rest is just used for verification after
# each read operation.
last_char = term_chars[-1]
# Consequently, it's illogical to have the real termination character
# twice in the sequence (otherwise reading would stop prematurely).
if term_chars[:-1].find(last_char) != -1:
raise ValueError, "ambiguous ending in termination characters"
vpp43.set_attribute(self.vi, VI_ATTR_TERMCHAR, ord(last_char))
vpp43.set_attribute(self.vi, VI_ATTR_TERMCHAR_EN, VI_TRUE)
self.__term_chars = term_chars
def __set_term_chars(self, term_chars):
"""Set a new termination character sequence. See below the property
"term_char"."""
# First, reset termination characters, in case something bad happens.
self.__term_chars = ""
vpp43.set_attribute(self.vi, VI_ATTR_TERMCHAR_EN, VI_FALSE)
if term_chars == "" or term_chars == None:
self.__term_chars = term_chars
return
# Only the last character in term_chars is the real low-level
# termination character, the rest is just used for verification after
# each read operation.
last_char = term_chars[-1]
# Consequently, it's illogical to have the real termination character
# twice in the sequence (otherwise reading would stop prematurely).
if term_chars[:-1].find(last_char) != -1:
raise ValueError, "ambiguous ending in termination characters"
vpp43.set_attribute(self.vi, VI_ATTR_TERMCHAR, ord(last_char))
vpp43.set_attribute(self.vi, VI_ATTR_TERMCHAR_EN, VI_TRUE)
self.__term_chars = term_chars
def __del_timeout(self):
timeout = self.__get_timeout() # just to test whether it's defined
vpp43.set_attribute(self.vi, VI_ATTR_TMO_VALUE, VI_TMO_INFINITE)
def __set_data_bits(self, bits):
if not 5 <= bits <= 8:
raise ValueError, "number of data bits must be from 5 to 8"
vpp43.set_attribute(self.vi, VI_ATTR_ASRL_DATA_BITS, bits)
def __set_baud_rate(self, rate):
vpp43.set_attribute(self.vi, VI_ATTR_ASRL_BAUD, rate)
def __set_send_end(self, send):
if send:
vpp43.set_attribute(self.vi, VI_ATTR_SEND_END_EN, VI_TRUE)
else:
vpp43.set_attribute(self.vi, VI_ATTR_SEND_END_EN, VI_FALSE)
def trigger(self):
"""Sends a software trigger to the device."""
vpp43.set_attribute(self.vi, VI_ATTR_TRIG_ID, VI_TRIG_SW)
vpp43.assert_trigger(self.vi, VI_TRIG_PROT_DEFAULT)
def __set_baud_rate(self, rate):
vpp43.set_attribute(self.vi, VI_ATTR_ASRL_BAUD, rate)
def __set_timeout(self, timeout):
if not(0 <= timeout <= 4294967):
raise ValueError, "timeout value is invalid"
vpp43.set_attribute(self.vi, VI_ATTR_TMO_VALUE, int(timeout * 1000))
def trigger(self):
"""Sends a software trigger to the device."""
vpp43.set_attribute(self.vi, VI_ATTR_TRIG_ID, VI_TRIG_SW)
vpp43.assert_trigger(self.vi, VI_TRIG_PROT_DEFAULT)
def __set_timeout(self, timeout):
if not(0 <= timeout <= 4294967):
raise ValueError, "timeout value is invalid"
vpp43.set_attribute(self.vi, VI_ATTR_TMO_VALUE, int(timeout * 1000))
def __set_end_input(self, termination):
vpp43.set_attribute(self.vi, VI_ATTR_ASRL_END_IN, termination)
def __set_parity(self, parity):
vpp43.set_attribute(self.vi, VI_ATTR_ASRL_PARITY, parity)
def __set_data_bits(self, bits):
if not 5 <= bits <= 8:
raise ValueError, "number of data bits must be from 5 to 8"
vpp43.set_attribute(self.vi, VI_ATTR_ASRL_DATA_BITS, bits)
def __set_parity(self, parity):
vpp43.set_attribute(self.vi, VI_ATTR_ASRL_PARITY, parity)
def __del_timeout(self):
timeout = self.__get_timeout() # just to test whether it's defined
vpp43.set_attribute(self.vi, VI_ATTR_TMO_VALUE, VI_TMO_INFINITE)
def __set_end_input(self, termination):
vpp43.set_attribute(self.vi, VI_ATTR_ASRL_END_IN, termination)
def __set_send_end(self, send):
if send:
vpp43.set_attribute(self.vi, VI_ATTR_SEND_END_EN, VI_TRUE)
else:
vpp43.set_attribute(self.vi, VI_ATTR_SEND_END_EN, VI_FALSE)
