Powering Leonardo USB Midi Out

Hi

I am trying to create a mobile interface to the Line 6 M13 Guitar Multieffects - essentially by sending bluetooth to an arduino leonardo, and getting the leonardo to produce the midi which will change the controls on the M13.

The part where I am stuck is getting the midi from the Leonardo to the M13. I (probably naively) thought I could use a 9v battery, then use a usb midi to midi cable converter (the M-Audio Uno) to connect from the Leonardo’s micro usb connector - and then have the M-Audio’s Midi din plugs connect to the M13.

That didnt work - and my first hunch is that the microusb from the Leonardo is not powered (unlike say the usb port of a computer). (I have definitely checked that the arduino is sending the correct midi messages when it is connected to the computer.)

Therefore my questions are:

  1. is this hunch likely to be correct (that the microusb from the leonardo, when the leonardo is powered by 9v battery does not give enough power to support whatever operations the usb to mid converter is doing)

  2. do there exist any things to boost up power in a usb connection

  3. what other ways of achieving this might there be?

Ideally I’d like to avoid much soldering because my eyesight is not all that good

  1. if so, is

1) is this hunch likely to be correct

No.

2) do there exist any things to boost up power in a usb connection

No.

What is wrong is that the Leonardo is a USB client device and the usb to midi cable converter is a USB client device, and you can only connect a client device to a host device.

Why not just use the serial output from the Leonardo's serial output to talk to your device over conventional MIDI?

Grumpy Mike - thanks very much for that - clarified a lot. Currently I have the digital pins 0,1 connected to the HC-05 for the bluetooth communication - but since i never do any bluetooth out as such, I am assuming i could just use digital pin 1 for Serial.print() for the midi? (Though in reality, it would be good to send an acknowlegement packet back to the phone after the command has been received)

Or might it be a better idea to get a Due or Mega for more serial ports?

Anyway, thanks again for responding

am assuming i could just use digital pin 1 for Serial.print() for the midi?

Yes but on a Leonardo you would have to use Serial1.print() or to be more precise Serial1.write().

it would be good to send an acknowlegement packet back to the phone after the command has been received

Why not use software serial for the odd bluetooth communications?

Brilliant! Thanks so much