revert default of poll to False

Before the introduction of the Property, the default of the poll
property was False. I feel that this is a better default, as the
programmer should think about which parameters really need to be
polled.

+ change comment about poll property (meaning depends on Poller)
+ change name of Status datatype to StatusType (avoid name conflicts
  with Status enum type)

Change-Id: Ie405b10ce8dfe85b235dbe78c910b5b5ee22cbb1
Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/21407
Tested-by: JenkinsCodeReview <bjoern_pedersen@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>

secop/datatypes.py

@@ -40,7 +40,7 @@ __all__ = [
     'BoolType', 'EnumType',
     'BLOBType', 'StringType',
     'TupleOf', 'ArrayOf', 'StructOf',
-    'CommandType',
+    'CommandType', 'StatusType',
 ]
 
 # *DEFAULT* limits for IntRange/ScaledIntegers transport serialisation
@@ -941,7 +941,7 @@ class LimitsType(StructOf):
         return limits
 
 
-class Status(TupleOf):
+class StatusType(TupleOf):
     # shorten initialisation and allow acces to status enumMembers from status values
     def __init__(self, enum):
         TupleOf.__init__(self, EnumType(enum), StringType())

secop/params.py

@@ -25,7 +25,7 @@
 from collections import OrderedDict
 
 from secop.datatypes import CommandType, DataType, StringType, BoolType, EnumType, DataTypeType, ValueType, OrType, \
-    NoneOr, TextType
+    NoneOr, TextType, IntRange
 from secop.errors import ProgrammingError
 from secop.properties import HasProperties, Property
 
@@ -82,12 +82,14 @@ class Parameter(Accessible):
     from the config file if specified there
 
     poll can be:
-    - False  (never poll this parameter)
+    - False or 0 (never poll this parameter), this is the default
-    - True   (poll this every pollinterval)
+    - True or 1  (poll this parameter)
-    - positive int  (poll every N(th) pollinterval)
+    - for any other integer, the meaning depends on the used poller
-    - negative int  (normally poll every N(th) pollinterval, if module is busy, poll every pollinterval)
+      meaning for the default simple poller:
-
+        - True or 1 (poll this every pollinterval)
-    note: Drivable (and derived classes) poll with 10 fold frequency if module is busy....
+        - positive int  (poll every N(th) pollinterval)
+        - negative int  (normally poll every N(th) pollinterval, if module is busy, poll every pollinterval)
+        note: Drivable (and derived classes) poll with 10 fold frequency if module is busy....
     """
 
     properties = {
@@ -107,7 +109,7 @@ class Parameter(Accessible):
                                  ValueType(), export=False, default=None, mandatory=False),
         'export':      Property('Is this parameter accessible via SECoP? (vs. internal parameter)',
                                  OrType(BoolType(), StringType()), export=False, default=True),
-        'poll':        Property('Polling indicator', ValueType(), export=False, default=True),  # check default value!
+        'poll':        Property('Polling indicator', IntRange(), export=False, default=False),
         'optional':    Property('[Internal] is this parameter optional?', BoolType(), export=False, default=False),
     }