OTC v1.5 - ETC on Organelle

a small update for OTC , so bump to v1.5


  • fix some startup issue
  • stereo input for modes to use

(its a smaller update than I’d planned, but thought it was better to release, than sit on it waiting for me to have more time to do the extra development id planned esp. due to the startup fix, which might be very valuable to some)

OTC_Mother v1.5 : https://patchstorage.com/otc-etc-for-organelle-application/

no changes have been made to OTC_Installer, nor OTC_Web, so these so not need reinstalling.

to install OTC, please read this thread

important note : C&G have moved the ETC modes and manual to:

FAQ, part 2 (continued from other post, check that too )

  • will this work on the SDCard?
    yes, I run OTC off the sdcard, just place modes in /sdcard/Modes
  • I cannot find modes, where are they?
    see new links above, etc.io no longer exists.
  • Im using a new USB card do I need to reinstall?
    OTC_Installer installs to the internal SD card, so you do not need to re-install if you are using a different usb stick, only if you re-flash the OS image
  • which Organelle OS is supported?
    Organelle 3.0+ , but Id always recommend the latest, as that it what I test with.
  • it doesn’t work, what should I do?
    first read the other OTC post linked above, I spent a lot of time adding all sorts of information about potential issues, and what to try.
    also that posts details, what to do, and what i need if you want to report an issue.
    lastly read the notes below about testing… you can see how I ensure OTC works on my Organelles

place any support questions etc in this thread.
(again, please remember OTC is not supported by C&G)

it is not just a matter of installing OTC_Mother.zop, you need other things
please read that post thoroughly, before posting questions here, its saves us all time

change details

startup issue

I found whilst testing very occasionally OTC would fail to start, after investigation this turned out to be a bug in pygame for which I found a workaround.

I know some users had issues with OTC starting up on their Organelle’s I cannot promise this fixes it, it may or may not be related to your issue - unfortunately, we never got to a good explanation as to why OTC worked for most, but for a few it didn’t - so without the cause its impossible to know if this is a fix or not. all you can do is try it :slight_smile:

btw: generally I find its a good idea to have hdmi display connected and powered on before you start the Organelle - it seems to be a bit more ‘stable’ for me.

Stereo input

so the ETC is hardware limited to mono input, but the Organelle is not :slight_smile:

so modes now have the following available in OTC


etc.audio_in, is retained for compatibility with ETC, and is an average of left and right.
but now we have left and right too (obviously using these, will make your modes incompatible with ETC)

what I like about these, is it means your modes can reflect the space of your sound…
so when you pan a sound from right to left, your image can move with it, I found it really helps tie the visuals to the sound.


How I test OTC (and other patches e.g. Orac)

I thought I write a little note about I test OTC, and how I ensure that it should work on your Organelle.
and so perhaps give you ideas, on what to try if some thing is not working.

So, Im lucky enough to have two Organelles, these play two different roles

  • a ‘development’ Organelle
  • an ‘as factory release’ Organelle.

( I use both for music making :slight_smile: )

the development Organelle has lots of things installed, and is my quad core super beast… its what I play with ideas with as well, including install extra software - although, generally everything I do on it is compatible with a vanilla Organelle - I never rely on it, so before releasing I always to a test on the vanilla Organelle.

the vanilla Organelle, is just like an Organelle bought today from C&G,
and is for testing patches etc that I release for the Organelle.

to ensure this, I do the following:

  • I regularly re-flash the latest OS Image from C&G
    this means it has no other software installed, other than the official C&G release!
    I sometimes add my own patches Ive release, or extra C&G,
    but I never install patches/software other than from C&G and my own.
    (this is just practical, I can’t support all possible combinations of installs from other developers)

  • I now use the internal SD card, as its officially support by C&G, but I often test with a USB stick too.
    I never use original C&G supplied white USB stick, it is very unreliable!
    (generally most C&G patches work on the sdcard, and all mine without issue - I consider it a bug in the patch if they do not :wink: )

  • I then download the released version of software from patchstorage!
    so I know im testing what you are downloading.

  • I usually transfer it via Wifi and the C&G Patch Manager

  • I then install via the Organelle OS menu , “Install …”
    (following instructions I have provided, in case there are any special instructions!)

  • I then test the patch

specifically for OTC:

  • I use an HDMI monitor that I know works and run OTC to test it works correctly

as you can imagine, going thru this process does take me a lot of time, the flashing of the sdcard alone, takes 10-15 minutes… and if something doesnt work, I have to do it all again!

what does this mean for you?

if you follow the same procedure, then our Organelles should be identical from a software perspective,
so any issues theoretically are hardware related.

but this requires you to re-flash the Organelle, which is not usually required,
but if you find OTC is not working, then perhaps something you have installed, as altered its state in an incompatible way.

an interesting addition to this.
I used to test upgrading from Organelle 1.0->2.x->3.x, Ive stopped doing this, as frankly it took hours.
what this means, is potentially there is a difference between an Organelle that has been upgraded from 2.x to 3.x … so if you have gone this route, and have issues Id recommend re-flashing with the latest OS.
(again, generally this is unnecessary , but to rule out issues, this is the only way!)

1 Like

1.5 running smooth here :slight_smile:
Thanks !!

oh… not a big deal, but OSD still shows 1.2 (lower right corner)

Thank you!
It’s working perfectly here (and from the SD card).

1 Like

doh, Id forgotten Id put the version number there…Ive just put a version number in the log file :slight_smile:
I’ll go fix this and re-release it. as you say not an issue, but very handy when people are unsure what version they are using!

1 Like

oh sorry… more work…

nah, my fault for not doing it properly in the first place - thanks for noticing !
anyway, done and uploaded - Ive a pretty quick workflow , once im actually working on something :slight_smile:

1 Like

Great !! @thetechnobear all good now :wink:

1 Like

I just installed OTC for the first time tonight, and mine I’m blown away at how fun this is. Mark: I’m really grateful for all of your work on the Organelle. I was thinking of selling mine for a short time after getting Norns, but I can’t after trying this and ORAC. Thanks!


Everything working fine but is there a way to switch between mono and stereo input? The trigger modes only work with stereo input now, do they? Thank you :slight_smile:

Trigger modes work the same as they did previously. No change.

basically left and right are additions , the audio_in works as it did before.

It seems that when there is only a mono signal there is not enough volume to get into the trigger area :face_with_raised_eyebrow: I can not reach the yellow zone

Probably you have nothing on one of the channels that will make the average lower.
( I use a mixer so centre the signal for mono signals)

I guess I could change audio_in to be the left channel ( which is usually used for mono due to cables) - but that has the disadvantage that the triggers are solely based on left for stereo signals.

There’s really not enough options on the UI to make it switchable, at least at the moment - and for the time I have to do this.

I guess left=mono is the least painful option for now

Hello, i’ve been able to run OTC as everything loaded properly but the link for the modes is broken so i cant get the modes from that location. I believe i located at another address but when i start OTC it cant find the modes and i believe ive saved them properly on a brand new formatted usb stick. Maybe you can help, i think your work is fascinating and so rad!

I’m not sure to understanding well your problem.
Do you have create a folder called “Modes” (not “modes” !! ) ?

Hello, yes, i named it Modes

as stated at the top of the previous thread, I need to see the otc_mother.log

if OTC is starting but not listing the modes, then something is wrong with how you have done the modes, perhaps you have done something like put them in a subdirectory incorrectly.

e.g you should have something like

/usbdrive/Modes/0 - Sound & MIDI Evaluation/main.py

if this is not present, then its wrong :wink:

see “Troubleshooting - part 2”, and look to see if its finding the modes

the issue here, is your not telling me anything other than “it doesn’t work”
Ive not enough details, to know what you have done wrong - I cannot ‘guess’ what you did :wink:

I need a precise description of thats not working, and the also log file.
e.g. show me a screenshot of your usbdrive, with the folders expanded, so I can see you have done with the modes.

Thanks for all of your help, heres a shot of the folder for the modes.

i downloaded these from github.
I really appreciate your help and rad work!

ok, that looks fine.

what exactly are you seeing on the screen? does it display the mode names as it starting? does it just get stuck on the big black n white ETC load screen?

I really need to see the otc_mother.log file to see whats going on.

ok, thank you again. Heres what the log reads "start otc mother
init fb0
about to draw. size x = 1280, size y = 720, bpp = 32, y virtual = 1440
red offset = 16, blue offset = 0, green offset = 8
alpha offset = 24, alpha length = 8
line len whatever that is 5120
cleared bufs
start splash
start python
shared memfd open() failed: Function not implemented
MIDI ch file I/O error(2): No such file or directory
set MIDI to ch 1
using input_id :-1:
no usb midi found
display info:<VideoInfo(hw = 1, wm = 0,video_mem = 7200
blit_hw = 0, blit_hw_CC = 0, blit_hw_A = 0,
blit_sw = 0, blit_sw_CC = 0, blit_sw_A = 0,
bitsize = 32, bytesize = 4,
masks = (16711680, 65280, 255, 0),
shifts = (16, 8, 0, 0),
losses = (0, 0, 0, 8),
current_w = 1280, current_h = 720

display modes:[(1408, 1056), (1280, 1024), (1280, 720), (1152, 864), (1024, 768), (960, 720), (800, 600), (768, 576), (640, 480), (640, 400), (512, 384), (320, 240), (320, 200)]
opening frame buffer…
hwscreen : <Surface(1280x720x32 HW)>
screen : <Surface(1280x720x32 SW)>
loading modes…
no modes found."

It loads and displays ETC on the tele screen then switches to “no modes found” the OLED on the organelle stays black the entire time.