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Re: Re: Command 9 Read Device Variables with Status

Message posted by Jens ( : 212.88.130.46) on 07 October 2011 at 07:36:18.

in reply to: Re: Command 9 Read Device Variables with Status posted by Romilly on 06 October 2011 at 14:57:29.

Okay, then i got it right. And if the Master asks for a Device Variable that the device does not support the device would send Response Code 2 (Invalid Selection).

How would the master ask for Device Variable 0 ? Do i, for example, have to define that Device Variable Code 42 is the code for my Device Variable 0?

I checked the Common Tables Specification. Table 34 (Device Variable Codes) only contains Codes for Battery life, Percent Range, Primary Variable, Secondary Variable, Tertiary Variable and Quarterny Variable. That confused me a little, because there is a Device Variable Code for every Dynamic Variable up to four Variables. So it seems that Device Variables and Dynamic Variables are the same.

Also the Text for table 34 says, that all of the codes in the table are standardized and therefore not included in the count returned by /Maximum Number of Device Variables/ in Command 0. Does that mean, if i only have a Primary Variable that represents the pressure, i have to return 0 for Maximum Number of Device Variables in Command 0 because every device has to return the Primary Variable for Device Variable Code 246?




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