dil5: working alfa version

Change-Id: Ib6bf2234633cc760fc771a3f5c0beb4cb63a0f6d

frappy_psi/logo.py

@@ -118,7 +118,7 @@ class DigitalActuator(LogoMixin, Writable):
 
     def initialReads(self):
         super().initialReads()
-        self.target = self.value
+        self.target = self.read_value()
 
     def set_fault(self, value, statustext):
         """on a fault condition, set target to value
@@ -229,6 +229,10 @@ class Value(LogoMixin, Readable):
         return IDLE, ''
 
 
+class DigitalValue(Value):
+    value = Parameter('airpressure state', datatype=BoolType())
+
+
 # TODO: the following classes are too specific, they have to be moved
 
 class Pressure(LogoMixin, Drivable):