Help me adding the minibrute 2S

[EtienneParmentier]

Hi ! I am the happy owner of an arturia minibrute 2S, and soon a microfreak which I hope to use with elektroid. I also have another windows laptop running windows with the arturia midi control center. I have made some research and it sounds like the minibrute 2S only uses sys-ex messages, so a reverse engineer is totally possible. If you teach me how to snoop on the midi connection betwween the windows laptop and the minibrute 2S I would gladly do some tedious work to make this device availlable in elektroid.

research to prove it's indeed possible : link to old forum post

[EtienneParmentier]

It looks like some functionalities are already working, but their are gaps: when connecting the mB2S to electroid, I have access to 128 'programms' which don't seem to do anything. There is also a [tanzanus] which gives me access to 2 Samples. I think it's an issue because the minibrute2S has no sampler (or maybe it does and we have found an hidden feature ?? Not probable IMHO).

[dagargo]

Adding support for the MiniBrute 2S would be totally awesome!

First of all, let's clarify some things about the current behaviour.

• You're seeing the KORG Volca Sample device because this device is no-MIDI, so that something is needed to be added there to indicate the users what are they using.
• The tanzmaus connector case is similar but it works on real MIDI devices. The problem in this case is that no handshake is possible, so the user selects a device over which the tanzmaus operations are gonna be performed. Thus, every device must be replicated for every no-handshake connector. Definitely, not nice because there will be many items in the combo that will confuse the user. I'd like to fix this but haven't found a simple way yet.
• There is a default connector that works on any device that doesn't have a specific one. It shows the 128 presets and send MIDI program changes when selecting them and activate the generic SysEx send and receive operations in the application menu. This makes sense to me.

Before getting into matter, do you consider that it'd be nice to hide the no-handshake and no-MIDI devices from users with an application setting? I could add this but I'm in the middle of the GTK4 migration in #157 and this would kind of break the UI file. I'd rather leave this for later but I think it's the way to go.

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In order to see the MIDI USB packets and the messages I'd recommend you to install WireShark but I think MIDI Console (Windows MIDI Services) allow this natively. The problem is that it's quite a new thing and it might not be available for your OS yet. I haven't tested though.

See WireShark installation for details. You'll need to install USBPcap but it's explained in there.

With any of this installed, you should see the traffic both ways when using Arturia MIDI Control Center and you might be able to start implementing the required functions and structures.

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Regarding the implementation, start simple and leave the GUI configuration for later if you want to do it.

Let's call the connector minibrute2 for now and hope that 2 and 2S are mostly compatible. We might want to name the required files minibrute2.c and minibrute2.h. Don't forget to indicate you're the Copyright owner of these files. I'd add you later as an author.

I'd suggest you to use one of the existing connectors as a template. You'll need to register it in regconn.c to make it work. I'd recommend the padcontrol one as it's the smallest. You might want to choose microbrute but there are many things that are not needed so you'll need to delete most of the code. It's up to you.

This struct should be at the end. You'll need to define MINIBRUTE2_NAME. Very likely, the regex is right in this example. This speeds up the handshaking as it searches for MIDI devices matching the regex.

const struct connector CONNECTOR_MINIBRUTE2 = {
  .name = MINIBRUTE2_NAME,
  .handshake = minibrute2_handshake,
  .type = CONNECTOR_TYPE_MIDI,
  .regex = ".*MiniBrute.*"
};

If the MiniBrute 2S uses the standard MIDI Device Inquiry, as other Arturia devices do, use the microbrute_handshake function as a template to implement minibrute2_handshake. Notice how the supported filesystems are added.

Once you have this, you'll need to implement the supported filesystems. Let's focus on the sequences.

You'll need something like this.

static const struct fs_operations FS_MINIBRUTE2_SEQUENCE_OPERATIONS = {
  .id = FS_MINIBRUTE_SEQUENCE,
  .options = FS_OPTION_SINGLE_OP | FS_OPTION_SLOT_STORAGE |
    FS_OPTION_SHOW_SLOT_COLUMN,
  .name = "sequence",
  .gui_name = "Sequences",
  .gui_icon = FS_ICON_SEQUENCE,
  .file_icon = FS_ICON_SEQUENCE,
  .readdir = minibrute2_read_dir,
  .download = minibrute2_download,
  .upload = minibrute2_upload,
  .load = common_file_load,
  .save = common_file_save,
  .get_exts = minibrute2_get_extensions,
  .get_upload_path = common_slot_get_upload_path,
  .get_download_path = common_slot_get_download_path_n
};

Finally, you'll need to implement minibrute2_read_dir (which would be really similar to the equivalent in the padkontrol connector), minibrute2_download, minibrute2_upload and minibrute2_get_extensions. That would be it for managing the sequences.

You might want to choose using text files as the input and output if you like or just binary SysEx files. For compatibility, I'd recommend using the same format Arturia MIDI Control Center uses.

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Definitely, way too much.

Let me know if I can help you with more precise information.

[EtienneParmentier]

Hi ! Thanks for your help, Hopefully I am a C programmer by trade so adding more C code is fine for me. I am not an auto-tools pro however, so I have no idea how to compile a debug build using this framework, it would help a lot if you could put up something in the "contributing" section of the docs. I have found a SO post but the good approach remains unclear to me: SO post.

Moreover the manual of the minibrute 2S does not mention any 'midi programs' so I believe this feature is not implemented ? What are even midi programs anyway ? Since the minibrute 2S does not have patch memory (it is semi-modular) I believe it does not support this feature.

[dagargo]

Great! Being you a C programmer is gonna make things much easier.

it would help a lot if you could put up something in the "contributing" section of the docs. I have found a SO post but the good approach remains unclear to me: SO post.

Yesterday, I was thinking about this as I was writing here. I'll definitely do it.

Moreover the manual of the minibrute 2S does not mention any 'midi programs' so I believe this feature is not implemented ? What are even midi programs anyway ? Since the minibrute 2S does not have patch memory (it is semi-modular) I believe it does not support this feature.

Absolutely! This feature makes only sense for MIDI devices that respond to program changes and makes no sense when using the MiniBrute or the MicroBrute or many others. It's just the default behaviour we might want with a generic MIDI device.

This filesystem would not be available on the minibrute2 connector as it happens with the MicroBrute unless you add it explicitely to the list during the handshake.

Consider that a device might have as many filesystems as needed. For instance, the MicroFreak has presets, samples and wavetables. In the case of the MiniBrute, only sequences are available, right? By reading the manual this isn't clear to me but it's the case of the MicroBrute.

[EtienneParmentier]

indeed, only sequences are availlable. No samples, no patches !