USB OTG and USB Host

836c26f40d1aad55

I’ts been some time that I looked into the midiphy SEQ v4+ Hardware and config.
I’d like to connect a USB Midi device like the nanokey to the USB port.
When using the OTG Connector I get the buttons lit as usual(so power seems to work) but no MIDI on the MIDI Monitor. Is it the wrong USB connector?
Software is V4.097.

What should I check? Hardware Jumpers or cable? Configuration?

0fc5608d995b44ff

@lp1977 - wow!! That is fantastic feedback in the shortest-possible time and really helpful to understand where the problem might be - thank you very much!

48484B i should be able to look into it, but currently can’t promise anything on when that could be - the latest LoopA software update date took far too long (kinda got carried away by song mode 🙂), still behind on all other time schedules 🙂.

Best regards,
Peter

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@48484B sadly, not all MIDI devices with SEQ v4+ in host mode handshake correctly, i’ve got two working devices (a Yamaha VPC1 and a Akai MPD32), these are working flawlessly, and i’ve got a more modern Midiplus X4 mini keyboard, which is not recognized.

Make sure to check that the USB switch is moved to host mode and that you power your SEQ v4+ with sufficient power (i.e. a powered USB hub), if it doesn’t work after that, it’s probably a USB MIDI handshake problem.

Best regards,
Peter

f2fc420ef03ad6e3

I just ran into this with Teensy based usb midi devices and it has to do with the way the STM usb host reads and parses the USB descriptor. If you dump the descriptor of your non-recognized device and take a look at it, you’ll probably see interface instances that don’t strictly comply with the outdated class compliant spec that the STM uses. In my case, the teensy based device’s usb descriptor does not include the Audio Control subclass descriptor, so it is not recognized by the SEQ v4+. Sequentix were able to overcome this on the Cirklon’s usb host by modifying the USB host handling of USB MIDI v2.0 devices without AUDIO CONTROL subclass descriptor. I wonder if something similar can be done on the SEQ v4+.

0fc5608d995b44ff

48484B no problem!

Just tested it over here with my Akai MPD - here’s what i did:

move the USB OTG switch to the OTG position (lower position)
plug in a USB cable from the OTG/Host port to your USB MIDI Class Device (hubs won’t work, some more modern units not complying to the old USB MIDI class descriptor won’t work until we could patch the STM USB driver, thanks again for that hint lp1977 !)
plug in the normal USB cable to your SEQ v4+ and power it up after you’ve plugged in your USB Device - basically establish all USB connections first, then power up
when the device is recognized it will look like this, best seen in the MIDI monitor - when you press a key (here a drumpad), the MIDI note will be shown in the upper USB1 monitor field:

Best regards,
Peter

836c26f40d1aad55

Thanks for the help!

I tried also the Polycom GM 5×5 with the same problem.
With “ USB switch is moved to host mode”, do you mean the “USB OTG” setting on the back of the unit?

Is there a difference in the power up sequence, so does the USB device need to be plugged already on power on.
In the Menu the USB1 etc show up with a “” (e.g. USB1).

c957655337c4cf59

Hi,
i have the same issue with my USB port.
I’ve tried 3 controllers so far (AKAI APC KEY25, M-AUDIO CODE61 and an Argon8 (with an external pwoer supply of course)), but without success. Even the lights don’t go on.
So could it be that there might be another problem?
I used a sufficient USB power supply. And the swith was turned to OTG.
And that also makes me wonder what the USB setting of the switch is for?

Kind Regards

0fc5608d995b44ff

dijf if the lights don’t go on, it might be a power problem. @latigid on knows best what could be going on from the hardware side.

From the software side, if a USB device is not recognized (as above), we should have the option to patch the USB driver in the future to enable better detection of non-STM32-standard MIDI-USB devices.

Regarding the USB switch: the SEQv4+ microcontroller is configured to support a single USB port, with the switch you select which USB port to use: using the standard USB port allows to attach your SEQ v4+ to a computer, creating four virtual SEQ v4+ USB devices on that computer, if it is the USB OTG port, then you can attach an external USB MIDI input device to your SEQ v4+.

Best regards,
Peter

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Did you jumper J8 on the USB PCB?

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latigid on I have forgotten to jumper! Now all works! Thank you for your help and quick response.
Kind Regards

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Great!

c957655337c4cf59

Hi, I had jumpered J8 and the midi keyboard got powered and the midi monitor even received data from it.
But not for long. I could only use it for one session and then it never communicated again. The power does go on, but no communication. It’s just weird that it did seem to work for a while.
I tried several power supplies, different usb cables and different midi keyboards..
What could be the problem?

17703227d9536da1

I don’t have any other information apart from what has been posted already. It’s unfortunately a bit hit-and-miss…

c957655337c4cf59

And how about this patching this USB driver to enable better detection of non-STM32-standard MIDI-USB devices?
It was mentioned earlier. How is it going with that?

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No further progress.