changed units PV readout to not read in constructors

slic/core/adjustable/pvadjustable.py

@@ -13,13 +13,12 @@ class PVAdjustable(Adjustable):
     def __init__(self,
         pvname_setvalue, pvname_readback=None, pvname_stop=None, pvname_done_moving=None, pvname_moving=None, 
         accuracy=None, active_move=False, process_time=0, wait_time=0.1, timeout=60, 
-        ID=None, name=None, internal=False
+        ID=None, name=None, units=None, internal=False
     ):
         pv_setvalue = PV(pvname_setvalue)
         pv_readback = PV(pvname_readback) if pvname_readback else pv_setvalue
 
         ID = ID or pvname_readback or pvname_setvalue
-        units = pv_readback.units
         super().__init__(ID, name=name, units=units, internal=internal)
 
         self.accuracy = accuracy
@@ -48,6 +47,18 @@ class PVAdjustable(Adjustable):
         self._pcm = make_pcm(pvname_done_moving, pvname_moving)
 
 
+    @property
+    def units(self):
+        units = self._units
+        if units is not None:
+            return units
+        return self.pvs.readback.units
+
+    @units.setter
+    def units(self, value):
+        self._units = value
+
+
     def get_current_value(self, readback=True):
         if readback:
             return self.pvs.readback.get()

slic/devices/general/smaract.py

@@ -50,8 +50,7 @@ class SmarActStage(BaseDevice):
 
 class SmarActAxis(Adjustable):
 
-    def __init__(self, ID, name=None, internal=False):
-        units = PV(ID + ":DRIVE.EGU").get() #TODO
+    def __init__(self, ID, name=None, units=None, internal=False):
         super().__init__(ID, name=name, units=units, internal=internal)
 
         self._move_requested = False
@@ -65,10 +64,23 @@ class SmarActAxis(Adjustable):
             set_pos  = PV(ID + ":SET_POS"),
             stop     = PV(ID + ":STOP.PROC"),
             hold     = PV(ID + ":HOLD"),
-            twv      = PV(ID + ":TWV")
+            twv      = PV(ID + ":TWV"),
+            units    = PV(ID + ":DRIVE.EGU")
         )
 
 
+    @property
+    def units(self):
+        units = self._units
+        if units is not None:
+            return units
+        return self.pvs.units.get()
+
+    @units.setter
+    def units(self, value):
+        self._units = value
+
+
     def get_current_value(self, readback=True):
         if readback:
             return self.pvs.readback.get()