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Re: Re: Analog values and the BSC schema



zocalodiscreto wrote:

>--- In xAP_developer@xxxxxxx, Kevin Hawkins <lists@u...>
>wrote:
>
>
>>zocalodiscreto wrote:
>>
>>
>>
>>>Hello all.
>>>
>>>I'm developing an Ethernet controller that should be compliant
>>>
>>>
>with
>
>
>>>the BSC xAP schema.
>>>
>>>
>>>
>>Sounds interesting, what hardware are you using there Daniel ?
>>
>>
>>
>>>According with the xAP standard, which is the
>>>best way of sending analog values?
>>>
>>>
>>>
>>>
>>  Well if your device is 'simple' then BSC would probably be the
>>easiest, and most suitable. However if there are more complex
>>
>>
>features
>
>
>>offered by your device you could create your own schema of
>>
>>
>course , or both.
>
>
>>>I'm thinking in physical values as temperature or humidity and,
>>>
>>>
>if I
>
>
>>>consider other applications, I could put the analog value in
>>>a "text" imput.
>>>
>>>example from the BSC specification:
>>>
>>>State=ON
>>>Text=23.5°
>>>
>>>Is correct my consideration or there is a better way of sending
>>>analog values, even using a diferent schema?
>>>
>>>
>>>
>>>
>>There is a 'LEVEL' based device type within the BSC schema but it
>>
>>
>is
>
>
>>best suited for values that go from 0 to some defined maximum
>>
>>
>value ,
>
>
>>perhaps it would be very suitable for humidity for example which
>>
>>
>is
>
>
>>0-100%.  . You don't report the value as a % in the message, you
>>
>>
>report
>
>
>>it as a fraction eg 100/1000   representing 10% and the
>>
>>
>granularity in
>
>
>>this example is  1000 units ie .1%   - a higher resolution device
>>
>>
>might
>
>
>>be 1000/10000 or something.
>>
>>Temperatures are more awkward as there is often no top 'limit' and
>>
>>
>also
>
>
>>the value can go negative. Hence usually the use of the 'TEXT'
>>
>>
>data type
>
>
>>to report these, this also allows the device to be switched
>>
>>
>between say
>
>
>>°C and °F nicely .  If your device ony reported a fixed range and
>>
>>
>didn't
>
>
>>go negative you could again use teh 'level' device.   The TOM10
>>
>>
>xAP
>
>
>>connector I wrote for example reports the 10 temperature sensors
>>
>>
>using
>
>
>>BSC Text categories.
>>
>>
>>
>>>Thanks in advance,
>>>
>>>Daniel.
>>>
>>>
>>>
>>>
>>>
>>Cheers Kevin
>>
>>
>
>
>Thanks Kevin for your response.
>
>Following your indications I'm going to publish temperatures and
>other analog values (humidity, voltage, power, etc) within
>the "TEXT" data. Next to the value, the units will appear.
>
>

That's fine - as I mentioned you can use Level for things like humidity
if you want.

>But, what about the "STATE" data? At the moment STATE will
remain on
>ON for every analog value although maybe I could use this data in
>order to declare some kind of alarm.
>
>
Either disregard it or use it as you wish, although it must be reported
in every BSC regardless. I use it on the thermostats for example to show
if there is a call for heat, an alarm is equally valid.

Kevin

>Regards.
>
>Daniel.
>
>
>
>
>





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