Nrpn messages?

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PongFu
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Joined:13 Dec 2011 17:37
Re: Nrpn messages?

Post by PongFu » 21 Dec 2011 02:12

No, it doesn't make any sense to me, first it's 63 and 62 then it's 99 and 98 and now it's 57, 52 and 252?

Macciza
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Location:Sydney, Australia.

Re: Nrpn messages?

Post by Macciza » 21 Dec 2011 04:33

Hi
Welcome to the world of computer/midi numerics . . the joys of binary and base16 aka Hexadecimal . . .
There are 10 types of people in the world - those who know binary and those who don't . . .
and Hexadecimal is easy if you have three extra fingers on each hand . . .

In that pic the numbers are in Hex - the 63 and 62 are hex for 99 and 98 ie 6*16 = 3, and 6*16 + 2 - does that help . . .
The MIDI monitoring program is showing hex but we talk CCs in decimal - the status B0 gives it away . . .
57 is just a parameter number for the Tetra and the 52 is the actual nrpn number Layer A 252 LayerB . . .

It does get confusing at times particularly when mixing bases and forgetting which base you need . . .

Have a good read of the manual regarding nrpn's . . .

Cheers
MM
iMac 2.8G i7 12G 10.6.8/10.7.2, Legacy Dexter/Lemur, Liine Lemur/iPad2, KMI SoftStep, 12Step & QuNeo , B-Controls, Mackie C4 etc
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mbncp
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Re: Nrpn messages?

Post by mbncp » 21 Dec 2011 23:16

To make it easier, you can download the free version of the Tetra editor http://www.soundtower.com/tetra/index.htm
Then set the midi port to a virtual midi port and see the output message with some midi spy app.
This is what I get when moving the o/c 1 frequency knob full right (max value)

msg chn cc val
Control 1 99 0
Control 1 98 0
Control 1 6 0
Control 1 38 120

so you would send 0xb0 , 99,0,98,0,6,0, 38, floor(x*120)

If the usb is not null (value greater than 127) then the full range is :
msb * 128 + lsb

example if the max value is
Control 1 6 2
Control 1 38 100
2*128 + 100 =356, which means that when x = 1.0, the value is 356

and you would send:
0xb0 , 99,0,98,0,6,floor((x*356)/128), 38, floor((x*356)%128)

if x is to the max ( = 1.0) then we would have
1.0 * 356 / 128 = 2.7 , floor(2.7) = 2; msb = 2
1.0 * 356 % 128 = 100; lsb = 100

if x is in half position ( = 0.5) then we would have
0.5 * 356 / 128 = 1.39 , floor(1.39) = 1; msb = 1
0.5 * 356 % 128 = 50; lsb = 50

Off course you can use the full formula in all situations, even if the total value is smaller than 128
If I take the first example where the max value is 120

1 * 120 / 128 = 0.93 , floor(0.93) = 0; msb = 0
1 * 120 % 128 = 120; lsb = 120

% means modulo, it returns the remainder of a division ( 10 % 3 = 1 is the same as 10- floor(10/3)*3 = 1


Hope you are a little more confused now ;)

PongFu
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Joined:13 Dec 2011 17:37

Re: Nrpn messages?

Post by PongFu » 22 Dec 2011 07:15

Yes, confused to the bone, and where do I copy and paste this beautiful nonsense?

dc_Sux
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Joined:07 Jan 2012 12:37

Re: Nrpn messages?

Post by dc_Sux » 07 Jan 2012 12:49

Hi,
I have been making good progress with my tetra editor, thanks to the excellent replies in this post. I am struggling, however, as soon as the parameter number is >127.

The script framework I have been applying to controllers is as follows (example being for a fader controlling LFO amount, parameter number 39):

decl target=0; // MIDI Target
decl nrpn_msb = 99, nrpn_lsb = 98; // NRPN MSB - LSB
decl data_msb = 6, data_lsb = 38; // DATA MSB - LSB
decl nrpn_param = 39;
decl null=0, value; //VARS
decl chan = 1; // MIDI Chan

value= LFO1Amt.x*127; // value * range

ctlout(target,nrpn_msb,null,chan);
ctlout(target,nrpn_lsb,nrpn_param,chan);
ctlout(target,data_msb,null,chan);
ctlout(target,data_lsb,value,chan);

This seems to work just fine. However I have been trying to map a multislider to control the 16 steps of the internal sequencer, and I'm runnning into problems. For the first 8 steps (parameter numbers 120-127), I have no issues, but once I get to step 9 and above (param number 128 onwards) it no longer works. I am presuming this is something to do with the null not being zero, but nothing happens if I change it to 1. Adjusting the sequencer nine step to 50 in the tetra editor, gives this readout on a midi monitor:

Control 1 99 1
Control 1 98 0
Control 1 6 0
Control 1 38 50

So does this mean that the null is now 1 for the NRPN MSB, but 0 for the Data MSB?
How can I change this ion my script?

Any help greatly appreciated!

dc_Sux
Newbie
Posts:9
Joined:07 Jan 2012 12:37

Re: Nrpn messages?

Post by dc_Sux » 07 Jan 2012 14:29

Figured it out:

If I change to end of my script to:

ctlout(target,nrpn_msb,(null+1),chan);
ctlout(target,nrpn_lsb,nrpn_param,chan);
ctlout(target,data_msb,null,chan);
ctlout(target,data_lsb,value,chan);

It seems to work

PongFu
Newbie
Posts:11
Joined:13 Dec 2011 17:37

Re: Nrpn messages?

Post by PongFu » 16 Jan 2012 06:59

so it does work when I leave out the "LFO1Amt." part

value= LFO1Amt.x*127; // value * range

changed it to

value= x*127; // value * range

execution set to
on frame
instead of
manual

but now the tetra screen displays the "LFO 1 amount" constantly and i can't use the other cc's I have set up or the tetra buttons.

Also I was looking for the LFO 4 FREQUENCY not the LFO 1 AMOUNT

ok..... LFO1Amt. is the name of your slider

dc_Sux
Newbie
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Joined:07 Jan 2012 12:37

Re: Nrpn messages?

Post by dc_Sux » 16 Jan 2012 07:52

PongFu wrote:s
Also I was looking for the LFO 4 FREQUENCY not the LFO 1 AMOUNT

ok..... LFO1Amt. is the name of your slider
Yes. Just replace the LFO1Amt with the name of your fader, and change the nrpn_param to whichever parameter number you want to control. I just gave the example for LFO 1 amount, parameter number 39.

Also you need to change the execution to On Expression, and put x into the script field of the variable.

dc_Sux
Newbie
Posts:9
Joined:07 Jan 2012 12:37

Re: Nrpn messages?

Post by dc_Sux » 20 Jan 2012 23:58


synthetic
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Joined:25 Feb 2012 00:32

Re: Nrpn messages?

Post by synthetic » 26 Feb 2012 01:42

I would like to set up a bunch of buttons to send NRPN messages. So far this thread and especially dc_Sux Tetra library have been a great help.

Right now I am using one of these scripts to send an NRPN. Execution on expression. It works great for a switch, sending 0 when the switch is off and 1 when the switch is on. But if I change the line from

value= switchname.x*1;

to

value= 1;

It sends a command when I touch the button and sends it again when I release the button. How do I get it to send only one time?

[edit] Figured out that it was sending this when the custom button behavior was a pad but not as a switch. I guess the fix is to make it a switch and have the on and off states look identical? Or is there a way to make a pad not send data when you let up?

[edit 2] The trick is to change the pulldown menu at the end of "On Expression= x" from ANY to _/ [arrow pointing to 1:00]

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