One knob to change the CC from 51 to two sequential CC values 61, and 29 at a certain threshold.

Question

MIDI Target Manufacturer(s): Line6

In modulations like chorus, flanger, my PodXT parameter-adjust dial starts with 12 selectable note values (such as quarter note, dotted half note, etc) using CC 51 with MIDI values of 001-013, then changes over to Hz by first sending CC 51 as MIDI value 000.

Upon this transition from sending note values to Hz for speed, it sends CC 61 LSB followed by CC 29.

1) Is it possible for a CC knob in MIDI Designer to initially send CC51 to select the 12 note values (MIDI 012 - MIDI 001, and then upon a threshold being reached (MIDI 000), have that same knob in MIDI Designer send CC 61, and CC 29?

2) Assuming there IS a way to do this, the next problem is CC 29 sends 0 while CC 61 iterates 11 steps. Once CC 61 reaches, for example, 124, the CC 29 iterates to a 1 and CC 61 starts all over again adding 11 to the previous number. This goes all the way up to CC 61 127, and CC 29 127

I attached an image of the midi log for an example. If I can cross this hurdle, I should have a pretty decent Line 6 Pod XT controller to share. In the photo, all the preceding values are CC 51 for note values. As I stated before, once CC 51 hits Zero, it requires to sequential CC values with one offset by 11.

** edit April 13 **

It works. It works!!! I thought I'd show the underbelly of the Midi control data. I just snapped to max value and hit record in Logic Pro and made the snap time 16 seconds. I made an animated GIF ~600Kb. Maybe it will come across as such.

Images

podxt.png

Visualization in Logic Pro on how the different channels work. Click for animation.

Answer 1

Reply #3 - building the named ticks for MSB and LSB control

re: That said, I still am unsure how to repeatedly increment CC #61 by 11 while CC #29 increments by 1 only when CC #61 reaches ~127 until they both reach 127.

Answer is a spreadsheet and named ticks.  Will need one control for MSB, one for LSB, and a super control.

You want to count to 127x127 (=16383) by increments of n x 11

16383/77 = 212.7, so we need 214 rows (213 + the row for zero)

First column just goes 0 to 213

Second column multiplies the first by n * 11, or 77 in this case

Row 214 exceeds 16383, (16401), so we paste in 16383.

Third column is our MSB, so we take the integer of second / 128

Fourth column is second MOD 128.

In MDP2, set up the MSB control, select named ticks, edit named ticks, delete all, then paste in the values from the MSB column

Repeat for the LSB control, pasting in the LSB column.

Create a new knob, select 14 bit Cc, select 214 ticks, Display Min/Max 1/214, and make it the supercontrol of the two controls above.  Ensure the MSB control is listed first in the subcontrols pane.  You can use named ticks to add appropriate labels to the supercontrol for the time or frequency.

Images

MSB LSB Table.png

Comments

Working on someting else, I realized this can be simplified.  Since the two Ccs are separated by 32, they are an automatic MSB/LSB pair.  So this only needs one control.  Build the knob for Cc 29, select 14 bit Cc, then paste the value column in for the named ticks.  MDP2 automatically handles the separation into MSB and LSB values, putting the LSB into Cc 61.

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I've been wrestling with this for a couple months and it finally clicked and - holy cow it works!  I used the spreadsheet version. I am lost on how to do this with the one knob allowing MDP2 to handle the separation though. But the longer way with the supercontrol works. I can now move on with getting the PodXT layout finished.

Answer 2

Reply #3 - building the named ticks for MSB and LSB control

re: That said, I still am unsure how to repeatedly increment CC #61 by 11 while CC #29 increments by 1 only when CC #61 reaches ~127 until they both reach 127.

Answer is a spreadsheet and named ticks.  Will need one control for MSB, one for LSB, and a super control.

You want to count to 127x127 (=16383) by increments of n x 11

16383/77 = 212.7, so we need 214 rows (213 + the row for zero)

First column just goes 0 to 213

Second column multiplies the first by n * 11, or 77 in this case

Row 214 exceeds 16383, (16401), so we paste in 16383.

Third column is our MSB, so we take the integer of second / 128

Fourth column is second MOD 128.

In MDP2, set up the MSB control, select named ticks, edit named ticks, delete all, then paste in the values from the MSB column

Repeat for the LSB control, pasting in the LSB column.

Create a new knob, select 14 bit Cc, select 214 ticks, Display Min/Max 1/214, and make it the supercontrol of the two controls above.  Ensure the MSB control is listed first in the subcontrols pane.  You can use named ticks to add appropriate labels to the supercontrol for the time or frequency.

Images

MSB LSB Table.png

Answer 3

Reply 1

Yes, using StreamByter.  And a couple of approaches possible there.

Brute force is just making three lookup tables for each of the output Cc values, in the sequence desired.  Build a synthetic SysEx command, with the appropriate number of ticks and labels, when SB sees the SysEx, it looks up and sends the appropriate values, blocking the synthetic SysEx command.  This would work for up to 256 ticks (size of SB arrays).

If the relationship of the messages can be defined logically, then instead of lookup tables they could be specified directly in the code.

If needed I can provide a template for the lookup approach that you could complete, or take a crack at a logic version.  

For the second, I would need a more complete definition of how the messages interact.   I am not seeing anything on Line 6 site that shows the interaction.  If there is, can you point me to it, or make a simple table.  Don't need every line, just the transitions.
Seq   CC51  CC61  CC29  Label
         01-12    na       na    4/4 - 1/32
          00        
et.

Comments

Thank you for your time and information.
I'll try to figure part one out. For part 2, the only indication is in Line 6 MIDI Continuous Controller Reference.pdf. It's not terribly obvious and I only discovered it snooping on the MIDI messages. Page 10 explains Paramater "Mod Param 1 LSB" simply as CC#61 with range 0-127. On page 8, it explains Parameter Modulation Param 1 as CC#29 with range 0-127.

I'll do my best to mimic what happens AFTER the transition from the tempo-sync'd note values to Hz:
I could have order backwards but the essence is this...
for the first frequency:
CC 61 sends 010
CC 29 sends 000

then after one detent on the knob
CC 61 sends 21
CC 29 sends 000

CC 61 sends 32
CC 29 sends 000

CC 61 continues along until it reaches 120 (that highest number it can get to 127 before rolling over since it's 11 digit increments.)
THEN CC29 will increment itself one digit.

CC 61 sends 003  (which is 127-120 +3  I think.)
CC 29 sends 001

CC 61 sends 014
CC 29 sends 001
then it continues on  with CC 29 incrementing one every time CC 61 approaches a value of 127.

Ultimately, the end of the road is when both CC 61 and CC 29 have sent 127.

Answer 4

Reply 1

Yes, using StreamByter.  And a couple of approaches possible there.

Brute force is just making three lookup tables for each of the output Cc values, in the sequence desired.  Build a synthetic SysEx command, with the appropriate number of ticks and labels, when SB sees the SysEx, it looks up and sends the appropriate values, blocking the synthetic SysEx command.  This would work for up to 256 ticks (size of SB arrays).

If the relationship of the messages can be defined logically, then instead of lookup tables they could be specified directly in the code.

If needed I can provide a template for the lookup approach that you could complete, or take a crack at a logic version.  

For the second, I would need a more complete definition of how the messages interact.   I am not seeing anything on Line 6 site that shows the interaction.  If there is, can you point me to it, or make a simple table.  Don't need every line, just the transitions.
Seq   CC51  CC61  CC29  Label
         01-12    na       na    4/4 - 1/32
          00        
et.

Answer 5

Reply 2 (had to start new answer to include picture)

I got it now.  It is just counting up by 11 through the entire range, using an undefined MSB/LSB Cc pair.

This can be put on one control, but you will have a dynamic range problem.  The first 10 ticks control the notes, then the remaining 128x128 / 11 (~ 1490) ticks control the speed.  With these both on one control, it will be essentially impossible to accurately select one of the notes.  

Two thoughts.

Separate controls for notes and speed, with a show / hide control to select.  I use this often in my layouts (I built most of these before show / hide became avail, so I just have a switch - see picture).  Although, even if you do this, you have 1490 values on one MDP2 control, which can be unwieldy.  The advantage of this approach is SB is not needed - this can be done directly with MDP2 controls, including named ticks.

Or, downsample the time.  If you skip by 77 instead of 11, that is about 200 ish values, much more manageable than one with 1500 values.  With 200 values for time and 10 for notes, the control will be usable.

Since the control relationship is straight forward, we do not need the table lookup approach I first mentioned, which only works up to 256 values.  (It could work with downsampling.)

Images

note-rate.png

Comments

I will give it a shot. That looks very promising. I will have a separate control for the note divisions.
That said, I still am unsure how to repeatedly increment CC #61 by 11 while CC #29 increments by 1 only when CC #61 reaches ~127 until they both reach 127.

---

Will get you something tonight.

Answer 6

Reply 2 (had to start new answer to include picture)

I got it now.  It is just counting up by 11 through the entire range, using an undefined MSB/LSB Cc pair.

This can be put on one control, but you will have a dynamic range problem.  The first 10 ticks control the notes, then the remaining 128x128 / 11 (~ 1490) ticks control the speed.  With these both on one control, it will be essentially impossible to accurately select one of the notes.  

Two thoughts.

Separate controls for notes and speed, with a show / hide control to select.  I use this often in my layouts (I built most of these before show / hide became avail, so I just have a switch - see picture).  Although, even if you do this, you have 1490 values on one MDP2 control, which can be unwieldy.  The advantage of this approach is SB is not needed - this can be done directly with MDP2 controls, including named ticks.

Or, downsample the time.  If you skip by 77 instead of 11, that is about 200 ish values, much more manageable than one with 1500 values.  With 200 values for time and 10 for notes, the control will be usable.

Since the control relationship is straight forward, we do not need the table lookup approach I first mentioned, which only works up to 256 values.  (It could work with downsampling.)

Images

note-rate.png