Changes between Version 8 and Version 9 of Proposal

Timestamp:

May 27, 2013, 2:48:54 PM (11 years ago)

Author:

Frédéric

Comment:

--

Proposal

@@ -37 +37 @@
 
 # Instanciation of the weather station device object
-station = WeatherStation(name="weather", address="1.2.3")
+station = WeatherStation(name="weather_station", desc="My simple weather station example", address="1.2.3")
 
 # Linking weather station Datapoints to Group Address
@@ -46 +46 @@
 ETS.link(device=station, dp="wind_speed_limit", gad="1/1/5")
 ETS.link(device=station, dp="wind_alarm_enable", gad="1/1/6")
-
 }}}
 
-That's it! As you can see, concepts used here are not new... This device can be then used from any other real device of your installation, through GADs {{{1/1/1}}} to {{{1/1/6}}}. All you have to do, is to link the Communication Objects of your real devices to these GADs, using the '''ETS''' application. For example, the DP Nr 4 will send the {{{"Alarm"}}} value over the bus when the wind speed will reach the value stored in DP Nr 5, but only if the value of the DP Nr 6 as been set to {{{"Enable"}}}.
+''Note: I skipped some part of the code, like the device registration and other stuff like that''
 
+That's it! As you can see, concepts used here are not new... This device can be then used from any other real device of your installation, through GADs {{{1/1/1}}} to {{{1/1/6}}}. All you have to do, is to link the Communication Objects of your real devices to these GADs, using the '''ETS''' application. For example, the DP Nr 4 will send the {{{"Alarm"}}} value over the bus when the wind speed will reach the value stored in DP Nr 5, but only if the value of the DP Nr 6 as been set to {{{"Enable"}}}. By linking this alram object to the alarm entry of you sun blinds, you can save them from destruction!
 
+Ok, but how the device knows the current wind speed? Well, it does not... yet! Let's see how it can be done:
 
+{{{
+#!python
+from pknyx.api import Device, ETS
 
+# Weather station class definition
+class WeatherStation(Device):
 
+    # Datapoints (= Communication objects) definition
+    DP_01 = dict(name="temperature", dptId="9.001", flags="CRT", priority="low", initValue=0.)
+    DP_02 = dict(name="humidity", dptId="9.007", flags="CRT", priority="low", initValue=0.)
+    DP_03 = dict(name="wind_speed", dptId="9.005", flags="CRT", priority="low", initValue=0.)
+    DP_04 = dict(name="wind_alarm", dptId="1.005", flags="CRT", priority="high", initValue=""No alarm")
+    DP_05 = dict(name="wind_speed_limit", dptId="9.005", flags="CWTU", priority="low", initValue=15.)
+    DP_06 = dict(name="wind_alarm_enable", dptId="1.003", flags="CWTU", priority="low", initValue="Disable")
+
+    @Device.schedule.every(minutes=5)
+    def readWindSpeed(self):
+
+        # How we retreive the speed is out of the scope of this proposal
+        # speed = xxx
+
+        # Now, write the new speed value to the Datapoint
+        self.dp["wind_speed"].value = speed
+
+        # Check alarm speed
+        if speed >= self.dp["wind_speed_limit"].value and self.dp["wind_alarm_enable"].value == "Enable":
+            self.dp["wind_alarm"].value = "Alarm"
+
+# Instanciation of the weather station device object
+station = WeatherStation(name="weather_station", desc="My simple weather station example", address="1.2.3")
+
+# Linking weather station Datapoints to Group Address
+ETS.link(device=station, dp="temperature", gad="1/1/1")
+ETS.link(device=station, dp="humidity", gad="1/1/2")
+ETS.link(device=station, dp="wind_speed", gad="1/1/3")
+ETS.link(device=station, dp="wind_alarm", gad="1/1/4")
+ETS.link(device=station, dp="wind_speed_limit", gad="1/1/5")
+ETS.link(device=station, dp="wind_alarm_enable", gad="1/1/6")
+}}}
+
+All we do, here, is adding a method periodically called by the framework (every 5 minutes in the above example). In this method, we retreive the wind speed (not explained here), and give the value to the Datapoint Nr 3. If the value has changed from the previous call, the Datapoint will automagically transmit it to the bus (according to the flags, of course).
+
+We also check if the speed has reached the speed limit; if so, we change the corresponding Datapoint value, which wil, in turn, send the value on the bus if needed (a special value of the flag, like in '''linknx''', can force the value to be sent, even if it does not change).
+
+That's it for now. This is only a draft version; final implementation may change, according to feedback/suggestions I will get. But the core is all there. Again, the goal of the framework is to provide very high level tools to build a complete and powerfull KNX extension.
+
+== Other ideas ==
+