diff --git a/hardwarelibrary/communication/debugport.py b/hardwarelibrary/communication/debugport.py
index b7ebe45f..8839134b 100644
--- a/hardwarelibrary/communication/debugport.py
+++ b/hardwarelibrary/communication/debugport.py
@@ -59,8 +59,7 @@ def flush(self):
         self.buffers = [bytearray(),bytearray()]
 
     def readData(self, length, endPoint=None):
-        if endPoint is None:
-            endPointIndex = 0
+        endPointIndex = 0 if endPoint is None else endPoint
 
         with self.portLock:
             time.sleep(self.delay*random.random())
@@ -75,8 +74,7 @@ def readData(self, length, endPoint=None):
         return data
 
     def writeData(self, data, endPoint=None):
-        if endPoint is None:
-            endPointIndex = 0
+        endPointIndex = 0 if endPoint is None else endPoint
 
         with self.portLock:
             self.inputBuffers[endPointIndex].extend(data)
diff --git a/hardwarelibrary/devicemanager.py b/hardwarelibrary/devicemanager.py
index 05b3c988..46036ae6 100644
--- a/hardwarelibrary/devicemanager.py
+++ b/hardwarelibrary/devicemanager.py
@@ -93,7 +93,7 @@ def matchesPhysicalDevice(self, device):
             return False
         if self.idVendor != device.idVendor:
             return False
-        if re.match(self.serialNumber, device.serialNumber, re.IGNORECASE) is not None:
+        if re.match(self.serialNumber, device.serialNumber, re.IGNORECASE) is None:
             return False
 
         return True
diff --git a/hardwarelibrary/motion/rotationdevice.py b/hardwarelibrary/motion/rotationdevice.py
index f7486443..46899568 100644
--- a/hardwarelibrary/motion/rotationdevice.py
+++ b/hardwarelibrary/motion/rotationdevice.py
@@ -54,7 +54,7 @@ def doMoveTo(self, angle):
         self._debugOrientation = angle
 
     def doMoveBy(self, displacement):
-        self._debugOrientation += angle
+        self._debugOrientation += displacement
 
     def doHome(self):
         self._debugOrientation = 0
diff --git a/hardwarelibrary/motion/sutterdevice.py b/hardwarelibrary/motion/sutterdevice.py
index 5625bf13..8cb0a47c 100644
--- a/hardwarelibrary/motion/sutterdevice.py
+++ b/hardwarelibrary/motion/sutterdevice.py
@@ -49,7 +49,7 @@ def doInitializeDevice(self):
                 self.port.open(baudRate=128000, timeout=10)
 
             if self.port is None:
-                raise PhysicalDevice.UnableToInitialize("Cannot allocate port {0}".format(self.portPath))
+                raise PhysicalDevice.UnableToInitialize("Cannot allocate port for serial '{0}'".format(self.serialNumber))
 
             self.positionInMicrosteps()
 
diff --git a/hardwarelibrary/physicaldevice.py b/hardwarelibrary/physicaldevice.py
index 4fec4c1c..15ad4483 100644
--- a/hardwarelibrary/physicaldevice.py
+++ b/hardwarelibrary/physicaldevice.py
@@ -1,7 +1,7 @@
 from enum import Enum, IntEnum
 from threading import Thread, RLock
 
-import hardwarelibrary.utils
+from hardwarelibrary import utils
 from hardwarelibrary.notificationcenter import NotificationCenter
 import typing
 import time
diff --git a/hardwarelibrary/powermeters/powermeterdevice.py b/hardwarelibrary/powermeters/powermeterdevice.py
index d118b6a5..5b9208cf 100644
--- a/hardwarelibrary/powermeters/powermeterdevice.py
+++ b/hardwarelibrary/powermeters/powermeterdevice.py
@@ -28,11 +28,5 @@ def setCalibrationWavelength(self, wavelength):
         self.doSetCalibrationWavelength(wavelength)
         self.doGetCalibrationWavelength()
 
-    def measureAbsolutePower(self):
-        self.doGetAbsolutePower()
-        power = self.absolutePower
-        NotificationCenter().postNotification(PowerMeterNotification.didMeasure, notifyingObject=self, userInfo=power)
-        return power
-
     def doGetStatusUserInfo(self):
         return self.measureAbsolutePower()
diff --git a/hardwarelibrary/sources/cobolt.py b/hardwarelibrary/sources/cobolt.py
index fa877129..7b6e2255 100644
--- a/hardwarelibrary/sources/cobolt.py
+++ b/hardwarelibrary/sources/cobolt.py
@@ -6,6 +6,8 @@
 import time
 from threading import Thread, RLock
 
+globalLock = RLock()
+
 class CoboltCantTurnOnWithAutostartOn(Exception):
     pass
 
@@ -64,13 +66,14 @@ def doInitializeDevice(self):
             self.doTurnAutostartOn()
             self.doGetInterlockState()
             self.doGetPower()
-        except Exception as error:
-            if self.port is not None:
-                if self.port.isOpen:
-                    self.port.close()
+        except PhysicalDevice.UnableToInitialize:
+            if self.port is not None and self.port.isOpen:
+                self.port.close()
+            raise
+        except Exception:
+            if self.port is not None and self.port.isOpen:
+                self.port.close()
             raise PhysicalDevice.UnableToInitialize()
-        except PhysicalDeviceUnableToInitialize as error:
-            raise error
         
 
     def doShutdownDevice(self):
diff --git a/hardwarelibrary/spectrometers/base.py b/hardwarelibrary/spectrometers/base.py
index 6ebf95bb..b9429a94 100644
--- a/hardwarelibrary/spectrometers/base.py
+++ b/hardwarelibrary/spectrometers/base.py
@@ -147,7 +147,7 @@ def showHelp(cls, err=None):
        speed, etc...). More spectrometers will be supported in the future.
        Look at the class USB2000 to see what you have to provide to support
        a new spectrometer (it is not that much work, but you need one to test).
-""".format(__file__, ', '.join(Spectrometer.supportedClassNames)))
+""".format(__file__, ', '.join(Spectrometer.supportedClassNames())))
 
         # Well, how about that? This does not work in Windows
         # https://stackoverflow.com/questions/2330245/python-change-text-color-in-shell
diff --git a/hardwarelibrary/spectrometers/oceaninsight.py b/hardwarelibrary/spectrometers/oceaninsight.py
index b051d94f..7595def4 100644
--- a/hardwarelibrary/spectrometers/oceaninsight.py
+++ b/hardwarelibrary/spectrometers/oceaninsight.py
@@ -275,7 +275,7 @@ def doInitializeDevice(self):
                 self.epStatus = self.inputEndpoints[self.epStatusIdx]
 
             self.flushEndpoints()
-            self.sendCommand(b'0x01')
+            self.sendCommand(b'\x01')
             time.sleep(0.1)
             self.getCalibration()
         except Exception as err: