Hello everyone!
I’m very new to this, so apologies if my question is obvious, I’ve just not been able to find specific information for my use case.
The objective:
–To use minimum requirements in both code and circuitry to enable an Arduino Uno to send Midi to the Daisy Pod. The Pod would have the ‘Midi’ example patch flashed (simple oscillator waiting to receive noteOn messages).
How to wire up the Uno to the Pod?
My understanding is the Daisy Pod Midi input is configured as Type A, meaning the tip is the data (or sink, or Rx), the ring is voltage (ideally 3.3v but I read the D14 Rx pin is 5v tolerant, so should work without a voltage shifter?), and the sleeve is Ground. My confusion starts at the crossover between the two, and the path from TRS jack on the Pod to the actual pins of the Daisy. Ignoring best practice for now, can it be as simple as…
Arduino TX > TRS tip
Arduino 5v > TRS ring
Arduino GND > TRS sleeve
…or am I overlooking something?
Thanks in advance for reading this far and again for any clarity you can bring,
all the best!
You just need to add MIDI Out on the Arduino side (2 resistors and a MIDI connector). The MIDI connector could be either the standard 5 pin DIN (in that case you will need MIDI to trs type A cable) or stereo jack wired as MIDI Type A.
This is a great article to get you started: https://minimidi.world/
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Thanks KnightHill,
I can confirm that the Arduino outputs MIDI data, testing into a DAW through my interface, it’s running code:
#include <MIDI.h>
MIDI_CREATE_DEFAULT_INSTANCE();
void setup()
{
pinMode(LED_BUILTIN, OUTPUT);
MIDI.begin(MIDI_CHANNEL_OFF);
}
void loop()
{
digitalWrite(LED_BUILTIN, HIGH);
MIDI.sendNoteOn(42, 127, 1);
delay(1000);
MIDI.sendNoteOff(42, 0, 1);
digitalWrite(LED_BUILTIN, LOW);
delay(1000);
}
I’ve now wired up the Arduino to Daisy (loaded with the Midi example of the DaisyDuino>Pod examples) using a 3.5mm TRS to breadboard pins I had prepared.
Arduino Tx > 220Ohm resistor > TRS tip
Arduino 5v > 220Ohm resistor > TRS Ring
Arduino GND > TRS Sleeve
No joy, I also tried triggering it with the same Midi device that I used to verify that my DAW input was working correctly to no avail.
In my first attempt at connecting the Arduino and Daisy, I had mistakenly thought there was only two connections in the Daisy’s Midi in (Sink and Current or Sink and Ground, I really had no clue), and so joined the ring and sleeve to make sure at least one of them was connecting to the female jack on the Pod. Might that have damged the Pod/Daisy? I’ll see about testing it with a friend to verify on a know setup and regroup.
All the best!
It it possible, but unlikely, to damage Pod’s MIDI in, as it is opto-isolated.
You didn’t specify what is the MIDI interface of your DAW. Do you have an external MIDI host for that purpose or something else?
In my experience, testing MIDI TRS is a lot harder than the older DIN connectors, because there are so many different ways to wire the TRS jack (type A, B, etc.).
As a side note, I have been looking for TRS MIDI hosts for some time, but cannot find anything. Some people recommend using a headphone splitter, but it is a bad idea, as it is not isolated.
Pod comes configured for Type A. Driving it from Arduino really is just a matter of two resistors, and connection to tip and ring.
What do you mean by ‘TRS MIDI host’ ?
Something like this, but with TRS jacks instead of DIN connectors:
https://m-audio.com/products/view/midisport-2x2-anniversary-edition
Thanks for the replies KnightHill (I’ve so far refrained from any Quest for the Holy Grail quotes 
) and tele_player!
Ok cool, I wondered whether it had some circuitry on the pod side, fingers crossed it’s ok!
DAW was Ableton, interface was Focusrite Scarlette 6i6, I verified the signal path using a Beatstep Pro (Type B to 5pin DIN into Focusrite). Then tested the Arduino using a butchered 5-pin DIN to the breadboard, piggy backing onto where I have the breadboard pins to TRS cable hooked up. Worked first time, so I know midi is getting through to at least the start of the TRS cable (I’ve tested from Arduino to TRS jack to check it’s actualy connected, all good with continuity checks).
What gets me sometimes is remembering which way is the 2 4 5 pins are when testing the cable (the diagrams show looking towards the face of a female 5pin DIN socket, right?).
My next attempt will be to try for some kind of “if I receive anything through RX, turn the pod LED on” or something, to verify whether there is indeed signal being received, if so then could it be a BAUD rate issue (would surprise me for an example, patch but I’m running low on ideas)?
Re the MIDI host your looking for, is that like a MIDI ‘hub’? To send, receive and split MIDI signals?
All the best!
Yes, I would like to have either a MIDI host or at least a splitter with a mix of DIN and TRS connectors. Ideally, the type of the TRS connectors should be selectable with dip switches. I am considering building one, as I was not able to find anything like that.
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I’m not sure I’ve seen what you describe called a MIDI host. An interface, maybe, when it has USB to talk to a computer. A splitter, maybe, when used to send MIDI to 2 or more receivers. Or a merger, when it… merges.
Good idea for a project. Maybe for a Teensy? Maybe include a USB Host port, so USB-only devices can play, too?
Teensy is an option. I am considering using RPI Pico, which is a lot cheaper.
Update: It’s alive!
Seems like there was a problem with the MIDI library, installed it and now the daisy pod is receiving from the arduino!
Thanks both for your input! All the best!
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