Merge pull request #181 from Jasper-Harvey0/DMM-Driver-Improvements

Dmm driver improvements

docs/source/release-notes.rst

@@ -8,11 +8,12 @@ Release Date XX/XX/XX
 
 New Features
 ############
-- 
 
 Improvements
 ############
 - Add logging of computer name to log file.
+- Update DMM driver with optional measurement delay to improve DMM model compatibility.
+
 
 *************
 Version 0.6.1

src/fixate/drivers/dmm/__init__.py

@@ -18,9 +18,7 @@
 
 
 def open() -> DMM:
-
     for DMM in (Fluke8846A, Keithley6500):
-
         instrument = find_instrument_by_id(DMM.REGEX_ID)
         if instrument is not None:
             # We've found a configured instrument so try to open it

src/fixate/drivers/dmm/fluke_8846a.py

@@ -1,7 +1,5 @@
 from threading import Lock
-from pyvisa import constants
 from fixate.core.exceptions import InstrumentError, ParameterError
-from fixate.core.common import mode_builder, deprecated
 from fixate.drivers.dmm.helper import DMM
 import time
 
@@ -11,6 +9,8 @@ class Fluke8846A(DMM):
     INSTR_TYPE = "VISA"
 
     def __init__(self, instrument, *args, **kwargs):
+        # Delay between call to self.measurement() and querying the DMM.
+        self.measurement_delay = 0
         self.instrument = instrument
         instrument.rtscts = 1
         self.lock = Lock()
@@ -42,28 +42,8 @@ def __init__(self, instrument, *args, **kwargs):
             "continuity": "CONF:CONTinuity",
             "diode": "CONF:DIODe",
         }
-        self._filters = {
-            "voltage_ac": "SENS:VOLT:AC",
-            "voltage_dc": "SENS:VOLT:DC",
-            "current_ac": "SENS:CURR:AC",
-            "current_dc": "SENS:CURR:DC",
-            "resistance": "SENS:RES",
-            "fresistance": "SENS:FRES",
-            None: "",
-        }
         self._init_string = ""  # Unchanging
 
-        self._resolution = {
-            "voltage_ac": "VOLT:RES",
-            "voltage_dc": "VOLT:RES",
-            "current_ac": "CURR:AC:RES",
-            "current_dc": "CURR:DC:RES",
-            "resistance": "RES:RES",
-            "fresistance": "RES:RES",
-            "capacitance": "CAP:RES",
-            None: "",
-        }
-
     @property
     def samples(self):
         return self._samples
@@ -100,11 +80,18 @@ def trigger(self):
         self._write("*TRG")  # Send trigger to instrument
         self._is_error()  # Catch errors. This might slow things down
 
-    def measurement(self):
+    def measurement(self, delay=None):
         """
         Sets up DMM triggering, creates list of measurements from the read buffer
+
+        delay: If not set, will wait for self.measurement_delay seconds before triggering a measurement. If set, will wait for delay seconds before triggering a measurement.
         returns: a single value as a float
         """
+        if delay is None:
+            delay = self.measurement_delay
+
+        if delay > 0:
+            time.sleep(delay)
         return self.measurements()[0]
 
     def measurements(self):
@@ -214,7 +201,6 @@ def _set_measurement_mode(self, mode, _range=None, suffix=None):
         resistance, fresistance. Reduces previous duplicate code.
         :param mode:
         :param _range:
-        :param _resolution:
         :return:
         """
         self.mode = mode
@@ -282,7 +268,6 @@ def diode(self, low_current=True, high_voltage=False):
         """
         Writes configuration string for diode to the DMM
         param _range: value set for the range
-        param _resolution: value set for the resolution
         """
         self._set_measurement_mode(
             "diode",
@@ -293,7 +278,6 @@ def continuity(self):
         """
         Writes configuration string for continuity to the DMM
         param _range: value set for the range
-        param _resolution: value set for the resolution
         """
         self._set_measurement_mode("continuity")
 

src/fixate/drivers/dmm/helper.py

@@ -28,7 +28,13 @@ def trigger(self):
         """
         raise NotImplementedError
 
-    def measurement(self):
+    def measurement(self, delay=None):
+        """
+        Trigger and return measurement from the instrument buffer.
+
+        delay: If True, waits for self.measurement_delay seconds then triggers a measurement.
+        returns: a single value as a float
+        """
         raise NotImplementedError
 
     def voltage_ac(self, _range=None):

src/fixate/drivers/dmm/keithley_6500.py

@@ -1,7 +1,5 @@
 from threading import Lock
-from pyvisa import constants
 from fixate.core.exceptions import InstrumentError, ParameterError
-from fixate.core.common import mode_builder, deprecated
 from fixate.drivers.dmm.helper import DMM
 import time
 
@@ -11,6 +9,8 @@ class Keithley6500(DMM):
     INSTR_TYPE = "VISA"
 
     def __init__(self, instrument, *args, **kwargs):
+        # Delay between call to self.measurement() and querying the DMM.
+        self.measurement_delay = 0.2
         self.instrument = instrument
         instrument.rtscts = 1
         self.lock = Lock()
@@ -80,10 +80,10 @@ def local(self):
         # So just set up a trigger loop. Requires *TRG to be sent to drop it out of the loop (call to remote()).
         self.samples = 1
         self._write("TRIG:LOAD 'EMPTY'")  # Load empty model
-        self._write(f"TRIG:BLOC:MDIG 1, 'defbuffer1', 1")
-        self._write(f"TRIG:BLOC:DEL:CONS 2, 0.1")
+        self._write("TRIG:BLOC:MDIG 1, 'defbuffer1', 1")
+        self._write("TRIG:BLOC:DEL:CONS 2, 0.1")
         self._write("TRIG:BLOC:BRAN:EVEN 3, COMM, 5")
-        self._write(f"TRIG:BLOC:BRAN:ALW 4, 1")
+        self._write("TRIG:BLOC:BRAN:ALW 4, 1")
         self._write("TRIG:BLOC:BUFF:CLE 5")
         self._write("TRAC:CLE")
         self._write("INIT")
@@ -117,11 +117,18 @@ def trigger(self):
         self._write("INIT; *WAI")
         self._is_error()
 
-    def measurement(self):
+    def measurement(self, delay=None):
         """
         Sets up DMM triggering, creates list of measurements from the read buffer
+
+        delay: If not set, will wait for self.measurement_delay seconds before triggering a measurement. If set, will wait for delay seconds before triggering a measurement.
         returns: a single value as a float
         """
+        if delay is None:
+            delay = self.measurement_delay
+
+        if delay > 0:
+            time.sleep(delay)
         return self.measurements()[0]
 
     def measurements(self):