Merge pull request #40 from ralph-group/dev/keithley2400

* Adding docs to Keithley 2400 and cleaning up functions

* Major update to Keithley 2400

* Replaced output wording with source for consistency

* Syntax fixes in Keithley 2400

* Updated Yokogawa 7651 to be consistent with Keithley 2400

* Another syntax fix in Keithley 2400

* Added get and set process hook for Instrument.control and measurement

* Added Keithley buffer class to share buffer code between Keithley 2000 and Keithley 2400

* Updating Keithley 2400 controls and buffer inheretance

* Major update to Keithley 2000, new controls and consistent syntax

* Major update to Yokogawa7651, new controls and consistent syntax

* Updated IV examples with new instrument controls

* Updated syntax for applying current and voltage

* Simplified IV example imports

* Updated IV procedures for setting current

* Worker handles startup errors more gracefully

docs/api/instruments/keithley/keithley2000.rst

@@ -4,4 +4,6 @@ Keithley 2000 Multimeter
 
 .. autoclass:: pymeasure.instruments.keithley.Keithley2000
     :members:
-    :show-inheritance:
+    :show-inheritance:
+    :inherited-members:
+    :exclude-members: ask, control, clear, measurement, read, setting, values, write

docs/api/instruments/keithley/keithley2400.rst

@@ -4,4 +4,6 @@ Keithley 2400 SourceMeter
 
 .. autoclass:: pymeasure.instruments.keithley.Keithley2400
     :members:
-    :show-inheritance:
+    :show-inheritance:
+    :inherited-members:
+    :exclude-members: ask, control, clear, measurement, read, setting, values, write

examples/Current-Voltage Measurements/iv_keithley.py

@@ -17,27 +17,18 @@
 log.addHandler(logging.NullHandler())
 
 import sys
-import random
-import tempfile
-import pyqtgraph as pg
 from time import sleep
 import numpy as np
 
 from pymeasure.instruments.keithley import Keithley2000, Keithley2400
 from pymeasure.instruments import Instrument
 from pymeasure.log import console_log
-from pymeasure.experiment import Results
 from pymeasure.display.Qt import QtGui
 from pymeasure.display.windows import ManagedWindow
-from pymeasure.experiment import Procedure, IntegerParameter, Parameter, FloatParameter
-from pymeasure.experiment import unique_filename
+from pymeasure.experiment import (
+    Procedure, FloatParameter, unique_filename, Results
+)
 
-class K2000(Keithley2000):
-    """ Temporary fix for PyMeasure 0.4.1
-    """
-    measure = Instrument.measurement(":read?", """""")
-    voltage = measure
-    current = measure
 
 class IVProcedure(Procedure):
 
@@ -51,20 +42,16 @@ class IVProcedure(Procedure):
 
     def startup(self):
         log.info("Setting up instruments")
-        self.meter = K2000("GPIB::25")
-        # Number of power line cycles (NPLC)
-        # Medium = 1 NPLC, 20 ms
-        self.meter.config_measure_voltage(self.voltage_range, nplc=1)
+        self.meter = Keithley2000("GPIB::25")
+        self.meter.measure_voltage()
+        self.meter.voltage_range = self.voltage_range
+        self.meter.voltage_nplc = 1 # Integration constant to Medium
 
         self.source = Keithley2400("GPIB::1")
-        #self.source.config_current_source(self.max_current*1e-3)
-        # Temporary fix for PyMeasure 0.4.1
-        self.source.write(":sour:func curr;"
-                   ":sour:curr:rang:auto 0;"
-                   ":sour:curr:rang %g;:sour:curr:lev %g;" % (
-                        self.max_current*1e-3, self.min_current*1e-3))
-        self.source.write(":sens:volt:prot %g;" % self.voltage_range)
-        self.source.output = True
+        self.source.apply_current()
+        self.source.source_current_range = self.max_current*1e-3 # A
+        self.source.complinance_voltage = self.voltage_range
+        self.source.enable_source()
         sleep(2)
 
     def execute(self):
@@ -77,9 +64,13 @@ def execute(self):
         log.info("Starting to sweep through current")
         for i, current in enumerate(currents):
             log.debug("Measuring current: %g mA" % current)
+
             self.source.source_current = current
+            # Or use self.source.ramp_to_current(current, delay=0.1)
             sleep(self.delay*1e-3)
+
             voltage = self.meter.voltage
+
             if abs(current) <= 1e-10:
                 resistance = np.nan
             else:
@@ -96,8 +87,7 @@ def execute(self):
                 break
 
     def shutdown(self):
-        self.source.source_current = 0
-        self.source.output = False
+        self.source.shutdown()
         log.info("Finished")
 
 

examples/Current-Voltage Measurements/iv_yokogawa.py

@@ -17,27 +17,19 @@
 log.addHandler(logging.NullHandler())
 
 import sys
-import random
-import tempfile
-import pyqtgraph as pg
 from time import sleep
 import numpy as np
 
 from pymeasure.instruments.keithley import Keithley2000
 from pymeasure.instruments.yokogawa import Yokogawa7651
 from pymeasure.instruments import Instrument
 from pymeasure.log import console_log
-from pymeasure.experiment import Results
 from pymeasure.display.Qt import QtGui
 from pymeasure.display.windows import ManagedWindow
-from pymeasure.experiment import Procedure, IntegerParameter, Parameter, FloatParameter
-from pymeasure.experiment import unique_filename
+from pymeasure.experiment import (
+    Procedure, FloatParameter, unique_filename, Results
+)
 
-class K2000(Keithley2000):
-    """ Temporary fix for PyMeasure 0.4.1 """
-    measure = Instrument.measurement(":read?", """""")
-    voltage = measure
-    current = measure
 
 class IVProcedure(Procedure):
 
@@ -51,14 +43,16 @@ class IVProcedure(Procedure):
 
     def startup(self):
         log.info("Setting up instruments")
-        self.meter = K2000("GPIB::25")
-        # Number of power line cycles (NPLC)
-        # Medium = 1 NPLC, 20 ms
-        self.meter.config_measure_voltage(self.voltage_range, nplc=1)
+        self.meter = Keithley2000("GPIB::25")
+        self.meter.measure_voltage()
+        self.meter.voltage_range = self.voltage_range
+        self.meter.voltage_nplc = 1 # Integration constant to Medium
 
         self.source = Yokogawa7651("GPIB::4")
-        self.source.config_current_source(self.max_current*1e-3)
-
+        self.source.apply_current()
+        self.source.source_current_range = self.max_current*1e-3 # A
+        self.source.complinance_voltage = self.voltage_range
+        self.source.enable_source()
         sleep(1)
 
     def execute(self):
@@ -71,8 +65,11 @@ def execute(self):
         log.info("Starting to sweep through current")
         for i, current in enumerate(currents):
             log.debug("Measuring current: %g mA" % current)
-            self.source.current = current
+
+            self.source.source_current = current
+            # Or use self.source.ramp_to_current(current, delay=0.1)
             sleep(self.delay*1e-3)
+
             voltage = self.meter.voltage
             if abs(current) <= 1e-10:
                 resistance = np.nan
@@ -90,7 +87,7 @@ def execute(self):
                 break
 
     def shutdown(self):
-        self.source.current = 0
+        self.source.shutdown()
         log.info("Finished")
 
 

pymeasure/experiment/workers.py

@@ -136,7 +136,19 @@ def run(self):
         log.info("Worker started running an instance of %r" % (self.procedure.__class__.__name__))
         self.update_status(Procedure.RUNNING)
         self.emit('progress', 0.)
-        self.procedure.startup()
+        # Try to run the startup method
+        try:
+            self.procedure.startup()
+        except Exception as e:
+            log.warning("Error in startup method caused Worker to stop prematurely")
+            self.handle_exception(e)
+            self.update_status(Procedure.FAILED)
+            self.recorder_queue.put(None)
+            self.monitor_queue.put(None)
+            self.stop()
+            del self.recorder
+            return
+        # If all has gone well, run the execute method
         try:
             self.procedure.execute()
         except (KeyboardInterrupt, SystemExit):