Added documentation

Change-Id: Id6e26a4c28fe080a55099cd54d0fa85c15946657

frappy_psi/qnw.py

@@ -16,7 +16,7 @@
 # Module authors:
 #   Oksana Shliakhtun <oksana.shliakhtun@psi.ch>
 # *****************************************************************************
-
+"""Temperature Controller TC1 Quantum NorthWest"""
 
 from frappy.core import Readable, Parameter, FloatRange, IDLE, ERROR, BoolType,\
     StringIO, HasIO, Property, WARN, Drivable, BUSY, StringType, Done
@@ -35,6 +35,13 @@ class SensorTC1(HasIO, Readable):
     channel = Property('channel name', StringType())
 
     def set_param(self, adr, value=None):
+        """
+        Set parameter.
+        Every command starts with "[F1", and the end of line is "]".
+        :param adr: second part of the command
+        :param value: value to set
+        :return: value converted to float
+        """
         short = adr.split()[0]
         # try 3 times in case we got an asynchronous message
         for _ in range(3):
@@ -80,6 +87,16 @@ class TemperatureLoopTC1(SensorTC1, Drivable):
         return self.get_param('MT')
 
     def read_status(self):
+        """
+        the device returns 4 symbols according to the current status. These symbols are:
+        ”0” or “1” - number of unreported errors
+        ”+” or “-” - stirrer is on/off
+        ”+” or ”-” -  temperature control is on/off
+        ”S” or “C” - current sample holder tempeerature is stable/changing
+        There could be the fifth status symbol:
+        ”+” or “-” or “W” - rampping is on/off/waiting
+        :return: status messages
+        """
         status = super().read_status()
         if status[0] == ERROR:
             return status