Is there a minimum required PID list for sub-devices?

[p_richart]

Hello all!

Does the list of minimum required PIDs apply to sub-devices?

Since only the root responds to discovery commands which are part of the minimum required parameters, I believe there is a strong argument for the answer to this question to be NO.

The remaining PIDs in the list are: DEVICE_INFO, SOFTWARE_VERSION_LABEL, IDENTIFY_DEVICE, and SUPPORTED_PARAMETERS (since our sub-device supports another publicly defined PID)

In our color changer we have a personalities that use a channel for fan control. We have implemented this by giving those personalities a fan sub-device.

The DEVICE_INFO and SUPPORTED_PARAMETERS commands are useful for our fan sub-device, SOFTWARE_VERSION_LABEL is benign, but IDENTIFY_DEVICE is not applicable at all.

Any thoughts?

Thanks - Patrick

[sblair]

Patrick,

The only message that is required to be supported for Sub-Devices is the SUPPORTED_PARAMETERS message. This is detailed in Section 9.3.

There is no requirement for any other messages to be supported and as you point out some would not make sense. Of course there are Sub-Devices where IDENTIFY_DEVICE and SOFTWARE_VERSION_LABEL would be useful but it completely depends on the application.

[p_richart]

Hi Scott,

I have the E1.20 ANSI CP/2003-1003r4 standard approved on March 31, 2006 and a copy of the RDM errata, neither of which has a section 9.3. Has an updated version been released?

[prwatE120]

I believe Scott meant 9.2.3

Peter Willis

[sblair]

Yes, I meant Section 9.2.3.