Sending Midi SysEx Messages

MarioMalidus · January 20, 2025, 10:51am

I can read out this sysex message from my Kemper Profiler when I move the mix knob from an overdrive plugin:
From “F0 00 20 33 00 00 01 00 34 04 00 05 F7”
to “F0 00 20 33 00 00 01 00 34 04 7F 7F F7”
Is there a way to make an object that get the value from an analog poti to continue send this sysex message?

Sorry, very newbee, and not familiar with script programming.

Regarding, Mario Malidus

Ksoloti · January 20, 2025, 11:25am

Hi, there are custom objects that can transmit sysex, I haven’t gotten around to tidying them up and publishing them in a library yet.

F0 00 20 33 00 00 01 00 34 04 00 05 F7 …
F0 00 20 33 00 00 01 00 34 04 7F 7F F7

So only the third-last and second-last values will change and describe a 14-bit mix value? Are you sure the lowest value is 00 05 and not 00 00? Would the Kemper thing explode if it received values lower than 00 05? (asking because value range down to 00 00 would be easier to code haha)

Also how does the Kemper connect to Ksoloti? USB MIDI? DIN MIDI?

Meanwhile, could you try this patch I found (and edited for your Sysex string)?

sysex_kemper_profiler.axp (5.1 KB)

It works with DIN MIDI here:

MarioMalidus · January 20, 2025, 11:53am

Oh, thank you very much! Looking forward to try this out!

I think 00 00 didn’t catch when I moved the knob.

So only the third-last and second-last values will change and describe a 14-bit mix value? -seems so

I connected my Kemper via USB. Kemper does supply the Ksoloti and also receives from it - from the beginning with no issues

Regards, Mario

Ksoloti · January 20, 2025, 12:19pm

Cool, for USB you’ll have turn off the MIDI DIN button and find the right USB host settings (untested…)

MarioMalidus · January 20, 2025, 1:19pm

Yeah, the Poti ist turned into Hex Code
But the Midi USB is the “USB device Port” not "USB host port"s
Is there an easy way to be able selecting the USB Device Port ?

Otherwise I’ll solder a DIN Pin to the Midi Connectors tomorrow…

Thank you, you help me out a lot!
Regarding Mario

Ksoloti · January 20, 2025, 1:41pm

Yeah that is as easy as changing the attribute text from USB_HOST_(something) to "USB_DEVICE_(something), I cant remember right now and you’d have to know where to look for these defines and the format changes (github)

Edit: USB sysex is currently only supported on the Host port … the code structure has been started but whoever worked on this back then only finished the HOST part. Another thing for the todo list.

MarioMalidus · January 20, 2025, 10:28pm

Hmm - did I do something wrong?
Just solderd a Midi DIN cable. Middle Pin 3 - Ground. Pin 2 - Sink, Pin 4 Source. Also did change pin 2 and 4. Connected to Ksoloti Ground - Pin M04 - and Pin M05. No Midi Signal to the Kemper.
Did I oversee something? Didn’t see any other Midi out Pins on the Ksoloti - hmm

Ksoloti · January 21, 2025, 2:25am

What you did sounds correct! For Clarity’s sake, the pinout on the DIN connector is counted in an unusual way: (possibly for legacy reasons)

(via Midi adapter - Making Sound Machines)

MO4, GND, and MO5 on the right Ksoloti header connect directly to the pin number:

MO4 → 4 Source
GND → 2 Shield
MO5 → 5 Sink

MarioMalidus · January 21, 2025, 10:18am

Strange. I don’t get any Midi Signals through all Midi Host Settings, neither through DIN. When I connect Midi Device USB - so that the Ksoloti is on - Im getting a shortcut through Pin MO5 and Ground.
I also tried to only use USB Power Supply on USB Device to only support the Ksoloti without any Signalchains - No luck.
Also tried USB Power Supply with Midi Host out, also no luck.

Seems like the Midi Signal only came through USB Device - hmm

Ksoloti · January 23, 2025, 2:57am

Is this still only regarding the Kemper sysex, or all MIDI in general? MO5 should not short to GND. What exactly is connected on the other side?

MarioMalidus · January 23, 2025, 1:41pm

Hi!

It’s MIDI in general! I did use the Objects which already worked with USB Device setting. Then turned these int DIN and all other Options from the Midi Host settings…

I only solderd some soldering (Female) Pins to the Ksoloti M- Pins. No Shortcut, everything clean. When I connect the Device Usb - where the Ksoloti also is powered from - The MO4 is getting 5V, and the M05 is on the 3,3V. That’s not how it schould be or?

Regarding, Mario

Ksoloti · January 23, 2025, 2:00pm

Your measurements are correct, MIDI is an “active low” (UART) serial protocol.

Pin 4 is pulled up to 5V via a 220 ohm resistor and pin 5 is pulled up to 3.3V via the microcontroller’s data pin (through a 100 ohm resistor in series).

(Image from 5-pin MIDI IN/OUT for Arduino - Sand, software and sound)

MarioMalidus · January 23, 2025, 3:26pm

Thank you all for your explanations!

Tried everything from beginning - no MIDI from M04, M05, GND. And no MIDI from USB HOST.

Ksoloti · January 24, 2025, 2:44am

Not sure what you’re sending where, and why via USB host? Something in your previous reports gave me the feeling the Kemper cannot be connected as a device (so that Ksoloti can be host)? The manual seems to confirm this:

The player will act as a USB host. (In USB, host and device roles are strictly defined, there has to be one acting as host and one acting as device. Host cannot talk to host, device cannot talk to device.)

On Ksoloti, the “Prog” port is the port where Ksoloti acts as a device. When you connect it to your computer, the computer is the host and talks to the device part of Ksoloti (upload patches etc.)
The “Host” port is always host, so only devices can be connected there (for example most, if not all, MIDI controllers).

Or are you testing MIDI in general? Where and how?

By the way, I still don’t know much about the Kemper Profiler but you may need to send a slightly different string, more like here:

github.com/schoko11/KEKO-Kemper-Control

modules/kemper.js

b86b250b0


      
          let pgOffsetPerf = [0,2,4,1,2];  //offsets for banks -> bank 1 offset 0 bank 2 offset 2 -> program change 2 with bank 2 ist the first slot in performance number 26...
          
          let tempStr = '';   //perf and rigsnames while scanning in perf. mode
          
          //these 3 const variables according to the server configuration
          let midiDeviceName;   //midi: "UCX1:0,1 sysex"  
          let sendIp;// = '127.0.0.1';      //send: 127.0.0.1:8000 
          let serverPort;// = '9000';       //port: 9000 
          
          const _sysReqStr = 'f0 00 20 33 02 7f 43 00 ';		//sysex for string request
          const _sysReqSinPar = 'f0 00 20 33 02 7f 41 00 ';  	//sysex for single parameter request
          const _sysReqMultPar = 'f0 00 20 33 02 7f 42 00 ';	//sysex for multi parameter request  
          const _sysReqExtStr = 'f0 00 20 33 02 7f 47 00 ';	//sysex for extended string request
          const _sysChgSinPar = 'f0 00 20 33 02 7f 01 00 ';	//sysex for change a single parameter
          const _sysReqRendStr = 'f0 00 20 33 02 7f 7c 00 ';	//sysex for parameter value as rendered string
          const _sysAnswSinPar = 'f0 00 20 33 00 00 01 00 ';  //sysex Answer / incoming single parameter
          const _sysAnswMulPar = 'f0 00 20 33 00 00 02 ';		//sysex Answer / incoming multi parameter
          const _sysAnswStr = 'f0 00 20 33 00 00 03 00 ';		//sysex Answer incoming string request
          const _sysAnswExtStr = 'f0 00 20 33 00 00 07 ';		//sysex Answer incoming extended string 
          const _sysAnswRendStr = 'f0 00 20 33 02 7f 3c 00 ';	//sysex Answer incoming rendered string
          const _sysRigName = '00 01';

Note that in the above project, F0 00 20 33 00 00 ... seems to be all “answer strings”, so it may be something the Kemper sends back for confirmation. All actual commands start with F0 00 20 33 02 7F ...

This manual has some info about the sysex format (chapter SYSEX Definition) and also uses 02 7F instead of 00 00:

MarioMalidus · January 24, 2025, 3:15pm

What I did:

I installed Midi Monitor - a software for my MacBook…

I send a specific Midi CC from Logic with a Fader from Logic’s old Midi Envoronment - Kemper ist instantly changing the Parameters.
Also tried the old Axolotti with the Midi DIN - Everything is working!
So the Kemper isn’t the Problem!
I tried to make a shortcut from the MO4 and MO5 to ground on my new Ksoloti, also a Midi Signal is coming in to my MacBook -
So the DIN cable is ok!
Did Change the Parameters in Live Mode and had a look on the Midi Monitor Software - No MIDI. (And sure, I did Change the Object to MIDI DIN out)

Im finished with my skills. Don’t know why the Ksoloti does not send any Midi Messages out from the MO4,MO5,GND

So because the Pin Measurements seems to be ok with 5V, 3,3V, and ground on the Midi output pins I think that there must be an issue with the objects in the software?! hm It´s out of my skills now…

MarioMalidus · January 24, 2025, 3:36pm

There is one thing I could do. Are the MO4 and MO5 Signals on a second place. Maybe the contact to the signal path is gone…

MarioMalidus · January 24, 2025, 3:57pm

And there is no way for you guys to do a MIDI SysEx sending Object for USB DEVICE Out??

Regarding Mario

Ksoloti · January 24, 2025, 4:06pm

MarioMalidus · February 3, 2025, 7:48am

Hi!

Everything works fine now with DIN Option. You’re advice to put an Resistor between MO5 and 5V workes perfectly. In my Case 250 Ohm!
Also the SysEx Sending Object works great!

Only how can I send multiple SysEx Commands in one Row? Like here:

This Array allows me to select different effects for a specific Slot in the Kemper Profiler. So I could choose between my favorite Effects with one button.

Also I’d need an Object which only changes the second last numbers (from 06 F7 to 01 F7)

Thank you for helping me out. Can I donate your helping?
Regards, Mario

Ksoloti · February 3, 2025, 11:57am

It is a hack but as long asnit works with toyr setup it’s okay. Ideally you could wire a buffer or Schmitt Trigger referenced to 5V after pin MO5 to get a clean, rock solid signal.

Thanks for sharing your experiences and progress by the way, I will address the 3.3V issue in hardware in the next board revision.

This is work in progress, I’ll clean up the code and try to come up with an intuitive way to modify single bytes and/or two-byte chunks in sysex tables. Something like that.

The idea is to define a sysex array with the required length, then modify any position of it in real time using blue inputs before sending it.

Topic		Replies	Views
MIDI Sysex Receive Object Axo Object Coding usb , midi , sysex , din	22	65	February 2, 2025
Midi SysEx Send Object General	9	44	March 3, 2025
MIDI Sysex Send Function Software midi , sysex , v110	9	99	January 29, 2025
Is AKSO discussion also allowed here? Question about Midi input Akso	15	239	October 3, 2024
Objects: modulation/control inlets or alternatives? General	5	61	April 21, 2025

Sending Midi SysEx Messages

Related topics