Re: Analog values and the BSC schema

[Kevin Hawkins <lists@xxxxxxxxxxxxxxxxx>]

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