USB wifi/bluetooth dongle?

#1

Hi

I'm realizing that this might be a very long shot. But I'm trying to understand the possibilities of the 'usb host' feature in the axoloti. If I've understood it correct: an normal usb midi controller should work with the axoloti core board without needing any drivers installed.

Would it be the same for an usb wifi/bluetooth dongle? I'm guessing not, but in that case what else would be needed. Some interesting apps for Android are able to send MIDI over wifi (but doesn't state that it would or would not work transmitting midi over an usb cable too). However, I'm not sure if any of them transmit anything via bluetooth. But I realize the difference in wifi (needing a network) and bluetooth (needing pairing transmitter + receiver).

/mike

#2

no, device support has to be built into the firmware, and it would not be an easy task (i don't think) to add wifi or bluetooth. (though would be interesting to look at midibox, to see if they have code to lift :smile: )

#3

Adding support for usb wifi or bluetooth dongles is very complex, and different dongle chipsets require specific driver code.

Adding an ESP8266 module on GPIO would be the easiest way to add wifi, but also requires development work.

#4

Thanks both of you. I suspected it to be quite complex. Otherwise others would already have done it elsewhere and I haven't seen much of that.

Conclusion is then to ask the developers if the apps already support midi transmission via usb, just that it isn't mentioned. And if not, suggest it in updates.

It feels like it would be easier to implement midi transmission via usb rather than via wifi. So I don't understand why an developer choose to omit a feature like that. But perhaps I'm totally wrong in thinking that way?

/Mike

#5

miketheman,

I found this Bluetooth to midi converter online: https://www.indiegogo.com/projects/puc-plus-universal-bluetooth-midi-interface#/story

I'd prefer a small one that is flush to the device, but this might do the trick. I'm not sure when they're shipping.

Like Johannes said, if you want it now, you can hack it together with some arduino modules or the ESP8266.

#6

Interesting indeed. Thanks for the heads up!

I´m looking a bit into some Android apps to use a cell phone as an MIDI controller towards the Axoloti. But most apps seems to need to use the device acting as a 'USB host'. Which I think that neither of my cell phones (Samsung S4 Mini or Samsung S5 Mini) can handle unfortunately.

Anyway, with WIFI. I don´t get the reason for the 'controller' (cellphone) to be a 'host' when it is supposed to be connected to something that will receive the MIDI commands? Isn´t the receiver seen as the host? I mean, comparing to an MIDI controller connected into the USB port of Axoloti. The Axoloti is the host.

/Mike

#8

Hmmm... uhm... okay. A bit more information (not necessarily less confused though). In the USB Midi Controllers thread. Technobear mentions:

"Axoloti can both act as a USB class compliant midi device (via the Micro USB port) for other devices act as host e.g. Computers/ iOS device, and as a USB Host for USB class compliant devices (via full size USB port) e.g midi controllers"

I remembered it wrong, I thought the Axoloti were only acting as a host. I don´t have any high hopes regarding my S4 Mini or S5 Mini, but will investigate it further.

#9

Axxoloti is composite USB device on the micro-usb connector, with both class compliant usb midi device interface (shows up as a midi port on Windows, Linux, Mac) and a vendor-specific bulk midi device (for the patcher).

I briefly tried connecting Axoloti to my S4mini with a micro-AB (on the phone) to female-A usb cable to the micro-USB-B (on Axoloti), but Axoloti is not getting power from the phone that way. Might be my cable.

#10

Thanks. Not sure I understand the technical description but nevermind, I´ll google it.

Does the Axoloti need to be powered from the cellphone? Or do you mean that it is 'being forced' to need it due to the design philosophy of the Axoloti (IIRC; anything connected to the micro USB port disconnects the DC-jack)?

Whereever I´m searching for information there are keywords as USB OTG, USB host, USB Tethering, USB Debug Mode. And on top of that: all seems to be mixed up with no clear information wether if it´s the same (which I doubt) and/or what´s what. It just adds to the confusion.

Liine Lemur:
"Connectivity — Lemur Android supports OSC and MIDI over Wi-Fi, as well as over USB with 3rd party tethering utilities."

TouchDaw:
"Later versions add support for MIDI over tethered USB connections, ADB and WebSockets. A free driver, available from our website, is required for those. As of version 1.4. the app can also be used with class-compliant USB MIDI interfaces on devices that support USB host mode."

MidiCommander:
"IMPORTANT NOTE: the Android device MUST BE CAPABLE of acting as USB-HOST. So, please, do not rate the app with a low score if the connected midi device is not recognized: it might be that your android device does not work in USB-HOST mode."

Anyway, whereever I´ve searched regarding S4 Mini / S5 Mini there are no indications of them being able acting as USB-hosts. I´ve found the USB-debug mode on my S5 Mini, but I haven´t found any information of what that really means. I find it hard to believe that USB debug mode itself suddenly would make any Android device working as USB host.

My S4 Mini screen is broken, but a relative easy/cheap fix if I repair it myself. Given that it would be fully functional after a repair, I don´t really have a use for it since I´ve got my S5 Mini. But it would have been wonderful if it could become a sort of remote midicontroller to the Axoloti, instead of bying a new tablet/phone only for that very purpose (not really justifiable).

Although I do have an Arduino Mini and Uno, Raspberry Pi 2. As well as the Up-board incoming (I think in april 2016 or so). An hack are an solution, but I think it might be too difficult to start with being a noob as I am...

#11

The opposite, applying a certain voltage on the DC input will disable getting powered from the USB device socket. DC jack takes priority.

"USB Tethering" is using the phone as a USB network interface to a pc. Midi or OSC over the network interface on android is far easier than usb access.

#12

Thanks. That was what I meant (the opposite), why didn´t I write that? :smile:

Interesting, I don´t know why but I´ve always believed that MIDI > network would be more difficult than MIDI > USB.

#13

this may be interesting to Axoloti users ... (and beyond)

about $50 expected... both din and usb forms should work with axoloti

#14

Not bad...
They say don't need battery even in the DIN version.
want to try it. Not sure about timing

#15

Although I wonder if it's class compliant or if your need to install a driver on your computer. My mx-49 Yamaha keyboard is not class compliant and uses a special driver. If this is the same it would only work on a computer which would be annoying but Yamaha is a pain like that sometimes.

I use http://www.tobias-erichsen.de/software/rtpmidi/rtpmidi-tutorial.html. For wireless midi network to connect iPhone/ iPad with my computer and midi keyboards. I have seen some $3 wifi chips on gearbest. If I knew more it would be a cool project to try and use Tobias's rtp midi protocol and a wireless chip to get axoloti running midi on wifi but I think this would take a lot of coding... Which I know 0 but I am wanting to learn :wink:

#16

An ESP8266 module on GPIO could probably handle midi-rtp, but I'd fear latency issues...
http://www.esp8266.com/viewtopic.php?f=8&t=6640

#17

to use the USB midi version it would have to be class complaint, but not for the DIN version.

MIDI over Bluetooth LE (Low Energy) this is supported my modern iOS and Macs ... afaik this is a draft standard that Apple have jumped on... so Im sure PCs/Android will follow suit in time, if not already.

Ive heard mixed reports of latency of Midi over bluetooth, though I suspect this is probably more jitter than latency given bandwidth of bluetooth , probably ok for midi data, but don't expect miracles if trying to do sync/clock.
(this is based reports Ive heard with people using the Seaboard RISE which supports this already)

anyway, I'm sure once its been available for a bit we will hear users experiences.

#18

I saw this:
Maybe usefull to comunicate with Axo via wifi

https://www.sparkfun.com/products/13678

#19

wow blast from the past.... I didn't know the AT command set had survived the demise of modems :smile: