i2c2midi – a DIY module that translates I2C to MIDI

phaelam · 2022-02-18T18:21:37.929Z

Thanks

No sooner do I ask that question this just got added to MG. Do you think this would be a go-between?

Expert Sleepers CVM-8

Expert Sleepers CVM-8 - Eurorack Module - CV to MIDI and CV to I2C converter

I swear every time I start thinking about some kinda way to go between message types ZZZ comes up with a solution days before I pose my questions. I don’t think it’s bi-direction tho.

mattallison · 2022-03-08T20:56:07.413Z

@attowatt do you have a Mouser Cart/Bom for MkII? Many of the parts cross over from Mk1, but the voltage regulator is different and SMD vs through hole.

Can you confirm the package type for the LM1117 for MkII?

attowatt · 2022-03-09T19:25:53.710Z

mattallison:

Can you confirm the package type for the LM1117 for MkII?

Sorry, I currently don’t have a Mouser Cart for you.
You can find BOMs here for MKI and here for MKII.

LM1117 is SMD, SOT-223.

mattallison · 2022-03-10T05:32:17.975Z

Thanks @attowatt, I sent the boards off for fabrication with JLCPCB and am now picking up the parts.

The only one I’m stuck on are the 10uF caps. The build images seem to indicate that you used either polarized Tantalum or Bipolar Ceramics capacitors on the MKII?

The schematic seems to indicate polarized caps, though the PCB photos don’t seem to indicate polarity on the silkscreen?

Can you provide some insight, or a part number?

attowatt · 2022-03-10T20:47:57.446Z

mattallison:

Can you provide some insight, or a part number?

I would say, any type of capacitor will do. Since the module width is only 2 hp, I tried to find caps as small as possible and ended up with the ceramic caps you see on the pictures.

attowatt · 2022-03-20T15:14:23.246Z

i2c2midi-OPs1427×947 72.8 KB

i2c2midi Firmware v 4.0

I am happy to release a new major firmware for i2c2midi, along with a beta firmware version of Teletype – featuring:

69 dedicated OPs for i2c2midi

The new firmware is the result of a joint collaboration with the amazing @scanner_darkly – who not only implemented i2c2midi’s Teletype OPs, but also joined forces with me in designing the feature set and OP concept.
We have been working really hard for the last 4 months to make the OPs as logical, intuitive and consistent with existing OPs as possible.

OPs

Thanks to the dedicated TT OPs, i2c2midi now can do much more. Here’s a breakdown of the main features:

Notes
- play MIDI notes (I2M.N) with specific velocity
- play notes on certain channel in one OP (I2M.NC)
- set note duration in ms (I2M.TIME)
- shift all notes up or down (I2M.SHIFT)
- repeat notes (I2M.REP)
- ratchet notes (I2M.RAT)
- set the minimum and maximum allowed note (I2M.MIN, I2M.MAX)
Chords
- define up to 8 different chords of maximum 8 notes (add, remove, insert, delete and set notes)
- play and transform chords in different ways (reversion, rotation, inversion, strumming)
- transform either individual chords (using index 1…8) or all chords at once (using index 0)
- set the length of each chord without changing the defined notes
CC
- send MIDI CCs (I2M.CC)
- send CCs on certain channel in one OP (I2M.CCC)
- offset individual CC controllers (I2M.CC.OFF)
- slew CC values to a new value within a certain time (I2M.CC.SLEW)
- use Teletype V values (0…10V) for CCs (I2M.CCV)
NRPN
- send NRPN (high-res CC) messages (I2M.NRPN)
- offset individual NRPN controllers (I2M.NRPN.OFF)
- slew NRPN values to a new value within a certain time (I2M.NRPN.SLEW)
MIDI misc
- send Program Change, Pitch Bend, Aftertouch
- send MIDI Clock messages (this feature still needs improvement!)
- MIDI Panic!!1
MIDI in (only MKII)
- i2c2midi stores MIDI notes and CCs incoming via USB, which can be accessed (“queried”) by Teletype
- get the last 16 notes and velocities (I2M.Q.N, I2M.Q.V)
- get the current value of a specific CC controller (I2M.Q.CC)
- get other last MIDI messages (last channel, last note, last note off last velocity, last CC controller, last CC value)
Channels (only MKII)
- send MIDI messages via TRS or USB individually, so i2c2midi basically features 32 MIDI channels now

Works with MKI and MKII

All features (except MIDI in and USB) work with i2c2midi hardware MKI and MKII.

If you want to use the new firmware for MKI, please comment out #define MK2 in line 35 of the main i2c2midi_firmware_v4_0.ino file.

Feedback

There are more ideas and features planned for the near future and we will continue further developing the feature set.

This a beta. There might be some bugs or future changes.
Testing and feedback is highly appreciated!

Links

Here is the complete documentation of all OPs:
https://github.com/attowatt/i2c2midi/blob/main/README.md#teletype-ops

Download the i2c2midi firmware here:
https://github.com/attowatt/i2c2midi/tree/main/MKII/firmware/i2c2midi_firmware_v4_0

Download the beta Teletype firmware here (I2M BETA 1):
teletype.zip (223.1 KB)

.

ParanormalPatroler · 2022-03-20T16:59:32.246Z

20 characters of congratulations for a job well done!!

Mad86 · 2022-03-20T19:41:33.338Z

WoW amazing !! Thank you both for all the work and new features. It’s so cool

Midi CC slew, NRPN, chords etc…

Lightbreaker · 2022-03-20T20:29:20.780Z

Absolutely incredible work, thank you @attowatt and @scanner_darkly!

cosmicsoundexplorer · 2022-03-20T23:03:55.812Z

This is just phenomenal work @attowatt and @scanner_darkly

mattallison · 2022-03-21T02:26:40.043Z

Thanks for this @attowatt and @scanner_darkly I actually finished my I2c2midi MK II this morning, here it is running on Ansible and sending out 2 MIDI tracks to my newly acquired BitBox Micro.

Great, easy build well documented source code and exceptional build guide.

If anyone down-under wants a set of PCB’s I have a couple extra.

scanner_darkly · 2022-03-21T02:51:21.205Z

it’s been a blast working on this project with @attowatt and i am excited to see what you all amazing people do with it!

here is teletype/i2c2midi sequencing and modulating poly cinematic and 6m0d6 modules via midi:

attowatt · 2022-03-21T21:12:41.628Z

Thank you @ParanormalPatroler @Mad86 @Lightbreaker @cosmicsoundexplorer !
When you update the module, don’t forget to check …

#define MK2 (comment out if using MK1)
and
#define USB_DEVICE (uncomment if using the Teensy USB jack)

… in the main i2c2midi_firmware_v4_0.ino file.

mattallison:

Great, easy build well documented source code and exceptional build guide.

Thanks a lot, really happy to hear that!

Mad86 · 2022-03-22T11:56:18.836Z

Sorry but I know nothing about editing on github…

So for a mk1 version do I have to write on the line 35 (or maybe simply delete it) ?

Hum I am totally noob. I made search on «comment out » on Github but I am not sure of what I do.

attowatt · 2022-03-22T12:46:50.245Z

Mad86:

So for a mk1 version do I have to write on the line 35 (or maybe simply delete it) ?

After you downloaded the all the .ino files, open i2c2midi_firmware_v4_0.ino with Teensyduino and go to line 35. Change it from
#define MK2
to
//#define MK2

Then compile and upload to the module.

Let me know if worked, otherwise I can also provide you the compiled hex file.

Lightbreaker · 2022-03-22T16:50:19.961Z

I just wanted to compile the firmware for MK1 and noticed that the clock speed in my Teensyduino’s software is still set to 120MHz (Overclock) because of a firmware I had to compile for O&C recently. I’m not sure what the correct clock speed is that I should set for i2c2midi or whether it even matters. Is there any harm in overclocking any Teensy?

Mad86 · 2022-03-22T16:59:19.922Z

I try to compile but I have an error message.

i2c2midi_firmware_v4_0:54:10: fatal error: MIDI.h: No such file or directory
#include <MIDI.h>
^~~~~~~~
compilation terminated.
exit status 1
MIDI.h: No such file or directory

Error i2c2midi948×903 83.2 KB

Obakegaku · 2022-03-22T17:11:20.557Z

Hey @Mad86 Looks like you are missing the required Arduino MIDI Library.
(I was missing the Ramp library whoops)
You should be able to download it from here

Then in the arduino programme there’s a section that let’s you add additional libraries, select the zip or folder of the downloaded Midi library from GitHub and it should work. If you get any more errors of similar description, double check the Libraries Used section of the i2c2midi Github.

Lightbreaker · 2022-03-22T17:16:57.727Z

Yeah, I just noticed I was missing the Ramp library too. Funnily, it didn’t complain about the Midi Library, even tho it doesn’t seem to be installed. I had some other errors while verifying the build, so I might just manually install all the necessary libraries.

@Mad86 You don’t necesserily have to download the libraries via Github, you could also try to find the correct ones via Teensyduino’s Library Manager. Since you seem to be on OSX, you can find it via Sketch → Include Library → Manage Libraries. Just watch out that you are installing the correct one, you can identify it via the author.

Edit: As for the clock speed, I switched the selected board forth and back and figured that 96MHz (Overclock) seems to be the default for Teensy 3.2.

Edit 2: Successfully updated the firmware on i2c2midi and Teletype. Just a little hickup when updating the firmware on Teletype, first, it flipped my display upside down, which was an easy fix as it can be permanently set with an OP, but the update also seemed to corrupt my scene memory. Every time I would restart Teletype it would tell me that it would overwrite all scenes if I pressed a button, which I didn’t, and it left me with a glitchy graphic when opening the scene menu. After power cycling again, erasing the scene memory, and playing in the backup everything was fine again. All seems to be working, so off to playing it is

Mad86 · 2022-03-22T20:09:14.439Z

Thank you @attowatt, @Obakegaku and @Lightbreaker for your reply but it seem not work.

All the needed library are installed and the Arduino Card library too but I have a new error message:

Arduino : 1.8.19 (Mac OS X), TD: 1.56, Carte : “Arduino Uno”

In file included from /Users/Desktop/i2c2midi/i2c2midi-e158fc310dea2e125e7d6630a69d049238e5ecdf/MKII/firmware/i2c2midi_firmware_v4_0/i2c2midi_firmware_v4_0.ino:59:0:
/Users/Documents/Arduino/libraries/i2c_t3-master/i2c_t3.h:29:2: error: #error “Sorry, i2c_t3 only works on Teensy LC and 3.x boards. Use Wire for Teensy 2.0.”
#error “Sorry, i2c_t3 only works on Teensy LC and 3.x boards. Use Wire for Teensy 2.0.”
^~~~~
exit status 1
Compilation error for Arduino Uno board

Did I forget something ?