Motormix pan knobs using Mackie MCU protocol

I need help settip up My pan knobs on my Motormix. I have the faders working I am using Waveform 10 and the MCU protocol for my midi controller and I can't seem to get the pan knobs to work but I see the incoming midi in the log from my DAW. So I tried to set the outgoing midi from the v-pots on the controller but it still not working. What am i doing wrong?


Just a thought here……Are your pan knobs continuous?
I’m not familiar with your MotorMix console. But, are your pan knobs sending 0-127, or just 0 and 127? (7F).
I have Roland control surfaces with the continuous knobs, where they bang out 0 or 7F depending on if you rotated them left or right. So I had to create a global variable and increment or decrement it every time the pan knobs sent out a 0 or 127 (rotated left or right. And of course had to limit that to within 0…127).


MCU Pan knobs (VPOTS) do not send absolute MIDI CC information.

The format of what they send is

B0 1i xx

Where i is the knob number 0-7

xx is an even more complex formula but in summary if it is 4x then it is a negative movement and if it is 0x then it is a positive movement.

The last x is the 4 least significant bits of the movement 0-15

There are actually 6 bits of movement, the other 2 bits are bit 2 and bit 1 of the first x

Here are some examples

B0 10 42 – VPOT 0 Counter clockwise 2 ticks

B0 10 03 – VPOT 0 Clockwise 3 ticks

B1 11 72 – VPOT 1 counter clockwise 50 ticks

B1 11 32 – VPOT 1 clockwise 50 ticks.

The last two examples are from the specification but I seldem if ever have seen a MIDI message number of ticks exceed 15.

So what you will have to do here if you want to convert to an absolute value is review our tutorial on turning a relative encoder to absolute and keep track of the position of the encoder in a global variable.

Are you planning on using this information to move an actual knob/fader or update an LED ring?

Steve Caldwell
Bome Q and A Moderator and
Independent Bome Consultant/Specialist



So I watched the video and downloaded the project. Now I have the knobs responding in the Daw with midi latch but I can’t seem to get it to respond in the MCU protocol. Also as you will see in the video all the pan knobs are not responding correctly.


Hi, sorry, the tutorial video is not “exactly” what you need for this. This is a different type of relative encoder than shown in the video. I’ve included an example for VPOT 0 only below. In this case I used CC100 for output.

The variable g0 is used to hold the current CC value. If you duplicate this translator for another vpot, you will need to assign a different global variable for each CC value you want to track.

For this VPOT (0) incoming is B0 10 qq

For VPOT 1 incoming would be B0 11 qq


The first line of rules here is


for the second translator I would recommend you use g1 so it would be


and then at the end of rule instead of


you would put


Then of course modify the output for the controller you want.


Here are all of the rules for VPOT0 to CC100

// get global variable
// lets determine direction look for 0x40
// determine if positive of negative
if rr==0 then ss=1
if rr==64 then ss=-1
// Now lets thake the rest 0x3f
// mulitply by ss to set direction
// never less than 0
if uu<0 then uu=0
//never greater than 127
if uu>127 then uu=127
// put it back into global variable