Vvvv + 4-channel Dimmerpack


I am trying to make vvvv send DMX signals to a 4-Channel Dimmerpack (Showtec MultiDim MKII) via the DMX4ALL Mini-USB-DMX-Interface:


I used this module/patch to get this working:


which fortunately not onyl works with the DMX4ALL Nano interface, but also with the DMX4ALL Mini that I have. :)

In essence it is working fine. I am able to send DMX signals to the Dimmerpack and I can dim my desktop lamp accordingly. However, this only works when I plug the lamp into the 1st of the Dimmerpack’s 4 channels. Plugging the lamp into the 2nd, 3rd oder 4th channel doesn’t work.

So, my question is:

Which part of the aforementioned module/patch do I have to change in order to address one of the other channels?

Sorry if this is a really newbish question, but I am absolutely new to vvvv and DMX :(

Your help is greatly appreciated! :))



did you use a single value or a spread of values as input for the DMX4all module/subpatch?

I guess, you only used one value (what basically is a spread with only one slice / spreadcount = 1) - right ?

If you use a spread with spreadcount 4 as a input, the values of the 4 slices of this spread should change the 4 channels of your dimmer pack (if the start adresse of the dimmer pack is set to one). If you use a spread with spreadcounf 512 you are able to change all 512 channels of this one DMX universe.

I hope, this explanation can help to solve your problem.


Hi Markus,

and thanks for your response. You are the creator of the patch right?

True, I only send single values one after another. Where do I set the spreadcount?

At the moment, my goal is not really to address all 4 channels at once (but I will have to do that later, too), but rather one particular channel other than the first. Is there no value that I can simply change in your patch which routes the incoming value to a different channel?

Btw, I attached my patch to this posting. The upper part of the patch is an OSC Decoder which receives OSC messages and forwards these values to the DMX part of the patch one after another.

Can you maybe modify the patch so that it

a) addresses one particular channels other than the first
b) sends a spread of 4 values to all 4 channels.

Of course only if you can do that quickly. I don’t want to hold you back.

Thanks a lot in advance! :)


OSC2DMX.v4p (41.4 kB)

do you want the same value to all 4 dimmer channels? if so use Select (Value) to select the incoming value 4 times. see attached patch.

OSC2DMX-2.v4p (42.7 kB)

Hi sunep, thanks for your efforts!

No, I want to send an incoming value to one particular channel (e.g. to channel 2 or 3). My current patch only sends the incoming values to channel 1.

Sending the same value to all 4 channels can be achieved by changing the hardware configuration of the Dimmerpack.

i think you just have to spread the osc address input of the decoder, it will then output 4 osc values from the osc channels and they will go to the dimmer channels… other than that, no change in the patch is needed.

maybe attached modified patch helps … you should read about Spreads in the Wiki … Spreads are one of the key and most important elements in vvvv.


OSC2DMX_3.v4p (47.4 kB)

Ok Markus I will do that. Thanks a lot for making this patch! I will test it later when I am back home.

Unfortunately it doesn’t work :(

As soon as I change the Index value no values make it to the Input box of the DMX part of the patch.
Putting a GetSlice node below the second Spread and setting it to the same Index solves that, but it’s still only channel 1 of the Dimmerpack that gets addressed this way. When I plug my lamp into any other channels it switches off.

For example when I set the Index to “1” (Index is starting at zero) and plug my lamp into channel 2, it doesn’t work. Same when I set Index to “2” and plug the lamp into channel 3 or any other one.

Actually I thought you would need to change something within the DMX part of the patch itself, for example these hex values ( 226 0xE2 and 227 0xE3), in order to address other channels. But I suppose these values have nothing to do with the channel number…?

Any advise?

hmm …

back home, i just tested with the USB-Interface and a DMX-Device connected.
At least the DMX-Part of the patch (everything below the first Line) is working as expected here.

Did you test the DMX-only-part without the OSC-part ? Doing the test please make sure, that your input value only has a spreadcount of 1 … you best use a “fresh” Io box, that has not yet have been connected to the OSC-output of your patch.
Or even better … directly connect a IO-Box with spreadcount >=4 to the DMX-Input … changing the first 4 values of this spread should change the four channels of your dimmer.
If this works (what i expect), the problem is somewhere on the OSC-side of your patch !? What spreadcount does the output of the OSC-part have ?

The hex values (226 0xE2 and 227 0xE3) you mentioned in your post are part of the protocol of the USB-DMX-interface. See attached documentation of the DMX4ALL-commands.


DMX4ALL_Commands.pdf (120.8 kB)