DEVICE_INFO - Device model ID

[berntd]

Hello

It has been a while again since I worked on RDM.
Does the model ID have to be different for devices of the same tyoe but with a different channel no?

I am asking here about dimmers in particular. Like same basic hardware and software but 6 channels or 12 channels ?

Best regards
Bernt

[sblair]

Bernt,

Generally this is what the PERSONALITY PID or Sub-Device count would be used if the quantity is going to change.

A well written controller probably wouldn't care or be confused, but some possibly could. I could make an argument for both cases here.

[berntd]

Hi Scott
That is what I thought. It has been done that way for some years now but I just wanted to check because I am working on something new.

Regards
Bernt

[ericthegeek]

A modular dimmer that accepts 12 dimmer modules, but only has 6 dimmers installed could use the same Model ID for both configurations.

But, I would argue that for fixed dimmers with a different number of channels, you should use a different Model ID for the 6 and 12 channel versions. This is especially true if they have a different Model Description string ("FancyDIM12" vs "FancyDIM6").

For a fixed dimmer, you *could* use the same Model ID with a different number of sub-devices, but I would strongly discourage this.

[prwatE120]

If you have the same hardware and basic firmware, but package and market the dimmer as two separate fixed size devices (i.e user cannot buy a 6way and instantly use it as a 12way), I would concur with ericthegeek and encourage the use of different ModelID AND Device Model Descriptions.

Although you could use personality to differentiate, it presumes that the personality is write protected. I would prefer to keep personality for such things as when you have 12 physical dimmers, but can present them as individual (12slot mode) or paired (6slot mode) etc, or a personality that inverts the control logic (slot value 0 is ON, slot value 0xFF is OFF, etc)

Hopefully it is relatively easy for your hardware to declare which build variant it is, or of not, add a Manufacturer Specific command (which need NOT be declared), to allow you to "SELECT" the correct ModelID/Device Model Description text at time of manufacture and test.

Peter

[berntd]

Since about 2008 I have been using the same model ID and description for the same dimmer range we make.

The subdevices count has been different for the channel variants.

The variants all run the same firmwre, which makes it a bit tricky to determine different IDs on the fly.

For the new firmware I am currently working on, I might change this if I can figure out a reasonable on the fly way way to do it.

Regards
Bernt