python-ivi · herm · Oct 27, 2015
diff --git a/ivi/interface/linuxgpib.py b/ivi/interface/linuxgpib.py
@@ -42,7 +42,11 @@ def parse_visa_resource_string(resource_string):
                 suffix = m.group('suffix'),
         )
 
-class LinuxGpibInstrument:
+# linux-gpib timeout constants, in milliseconds. See self.timeout.
+TIMETABLE = (0, 1e-2, 3e-2, 1e-1, 3e-1, 1e0, 3e0, 1e1, 3e1, 1e2, 3e2, 1e3, 3e3,
+             1e4, 3e4, 1e5, 3e5, 1e6)
+
+class LinuxGpibInstrument(object):
     "Linux GPIB wrapper instrument interface client"
     def __init__(self, name = 'gpib0', pad = None, sad = 0, timeout = 13, send_eoi = 1, eos_mode = 0):
 
@@ -139,3 +143,36 @@ def unlock(self):
         "Send unlock command"
         raise NotImplementedError()
 
+    @property
+    def timeout(self):
+        # 0x3 is the hexadecimal reference to the IbaTMO (timeout) configuration
+        # option in linux-gpib.
+        return TIMETABLE[self.gpib.ask(3)] * 1000.
+
+    @timeout.setter
+    def timeout(self, value):
+        """
+        linux-gpib only supports 18 discrete timeout values. If a timeout
+        value other than these is requested, it will be rounded up to the closest
+        available value. Values greater than the largest available timout value
+        will instead be rounded down. The available timeout values are:
+        0   Never timeout.
+        1   10 microseconds
+        2   30 microseconds
+        3   100 microseconds
+        4   300 microseconds
+        5   1 millisecond
+        6   3 milliseconds
+        7   10 milliseconds
+        8   30 milliseconds
+        9   100 milliseconds
+        10  300 milliseconds
+        11  1 second
+        12  3 seconds
+        13  10 seconds
+        14  30 seconds
+        15  100 seconds
+        16  300 seconds
+        17  1000 seconds
+        """
+        self.gpib.timeout(bisect(TIMETABLE, value/1000.))
diff --git a/ivi/interface/pyserial.py b/ivi/interface/pyserial.py
@@ -48,7 +48,7 @@ def parse_visa_resource_string(resource_string):
                 suffix = m.group('suffix'),
         )
 
-class SerialInstrument:
+class SerialInstrument(object):
     "Serial instrument interface client"
     def __init__(self, port = None, baudrate=9600, bytesize=8, paritymode=0, stopbits=1, timeout=None,
                 xonxoff=False, rtscts=False, dsrdtr=False):
@@ -123,7 +123,7 @@ def update_settings(self):
         else:
             self.serial.stopbits = serial.STOPBITS_ONE
 
-        self.serial.timeout = self.timeout
+        # timeout is handled in property setter
         self.serial.xonxoff = self.xonxoff
         self.serial.rtscts = self.rtscts
         self.serial.dsrdtr = self.dsrdtr
@@ -223,3 +223,12 @@ def unlock(self):
         "Send unlock command"
         raise NotImplementedError()
 
+    @property
+    def timeout(self):
+        return self.serial.timeout
+
+    @timeout.setter
+    def timeout(self, value):
+        self.serial.timeout = value
+        self.serial.writeTimeout = value
+
diff --git a/ivi/interface/pyvisa.py b/ivi/interface/pyvisa.py
@@ -47,7 +47,7 @@
         (e.__class__.__name__, e.args[0]))
     raise ImportError
 
-class PyVisaInstrument:
+class PyVisaInstrument(object):
     "PyVisa wrapper instrument interface client"
     def __init__(self, resource, *args, **kwargs):
         if type(resource) is str:
@@ -129,3 +129,11 @@ def lock(self):
     def unlock(self):
         "Send unlock command"
         raise NotImplementedError()
+
+    @property
+    def timeout(self):
+        return self.instrument.timeout
+
+    @timeout.setter
+    def timeout(self, value):
+        self.instrument.timeout = value
diff --git a/ivi/ivi.py b/ivi/ivi.py
@@ -1502,6 +1502,7 @@ def __init__(self, resource = None, id_query = False, reset = False, *args, **kw
         self._initialized = False
         self.__dict__.setdefault('_instrument_id', '')
         self._cache_valid = dict()
+        self._timeout = 2000
 
         super(Driver, self).__init__(*args, **kwargs)
 
@@ -1632,6 +1633,8 @@ def __init__(self, resource = None, id_query = False, reset = False, *args, **kw
                         +-------------------------+----------------------+---------------------+
                         | Prefer PyVISA           | False                | prefer_pyvisa       |
                         +-------------------------+----------------------+---------------------+
+                        | Timeout                 | 2000                 | timeout             |
+                        +-------------------------+----------------------+---------------------+
 
                         Each IVI specific driver defines it own meaning and valid values for the
                         Driver Setup attribute. Many specific drivers ignore the value of the
@@ -1686,6 +1689,18 @@ def __init__(self, resource = None, id_query = False, reset = False, *args, **kw
                           again.
                         * May deallocate internal resources used by the IVI session.
                         """)
+        self._add_property('timeout',
+                        self._get_timeout,
+                        self._set_timeout,
+                        self._del_timeout,
+                        """
+                        Set the device timeout. This value specifies how long the driver should
+                        wait for a response from the device before giving up. The value is
+                        specified in milliseconds.
+
+                        This property behaves the same way as pyvisa's timeout property.
+                        To set an infinite timeout, set it to None or use 'del timeout'.
+                        """)
 
         # inherit prefer_pyvisa from global setting
         self._prefer_pyvisa = _prefer_pyvisa
@@ -1718,6 +1733,8 @@ def _initialize(self, resource = None, id_query = False, reset = False, **keywar
                 self._driver_operation_driver_setup = val
             elif op == 'prefer_pyvisa':
                 self._prefer_pyvisa = bool(val)
+            elif op == 'timeout':
+                self._timeout = float(val)
             else:
                 raise UnknownOptionException('Invalid option')
 
@@ -1837,6 +1854,9 @@ def _initialize(self, resource = None, id_query = False, reset = False, **keywar
 
         self.driver_operation.invalidate_all_attributes()
 
+        if self._interface:
+            self._interface.timeout = self._timeout
+
         self._initialized = True
 
 
@@ -1891,6 +1911,18 @@ def _set_cache_valid(self, valid=True, tag=None, index=-1):
     def _driver_operation_invalidate_all_attributes(self):
         self._cache_valid = dict()
 
+
+    def _get_timeout(self):
+        return self._timeout
+
+    def _set_timeout(self, value):
+        self._timeout = value
+        if self._initialized and self._interface:
+            self._interface.timeout = value
+
+    def _del_timeout(self):
+        self._set_timeout = None
+
     def _write_raw(self, data):
         "Write binary data to instrument"
         if self._driver_operation_simulate: