OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

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SphericalSound
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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by SphericalSound » Tue Sep 29, 2020 8:07 am

four_corners wrote:
Sun Sep 27, 2020 8:12 pm
autodafe wrote:
Sun Sep 27, 2020 3:59 pm
yes, I have used caps on my buttons, the main concern would be the BluePill board (I have used some female headers for it)
also, the screens should be raised a bit...(maybe sing headers again..)
I was looking for some wooden boxes today at the flea market but couldn't find any...
Speaking of the BluePill on headers, I actually would advise anyone building this to use headers for the BluePill, as I actually had some issues with my BluePill and had to desolder it, leading to a giant mess. I ended up tearing some traces, and had to go through the schematic to find all the connections, and then wire a few jumpers. If I would have just put it on female headers, I would have saved about 3-4 hours of headache.
Sure, all peolpe should use sockets. Apart for that obvious reason, it could be that we do an alternative firmware that do it a polyphonic synth, so you just change the bluepill to switch between drummachine and polysynth

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by funketek » Tue Sep 29, 2020 9:38 am

I am using a PC, there are a few "warnings" that I get while uploading the program, but ultimately it says "success". Anyway, I learned a lot about Platformio in the process of (semi-)programming the Bluepill, but I think going with a pre-programmed one is my best bet right now. I emailed you about getting one. PM me or email me when you get a chance. You've been super helpful in troubleshooting this issue offline, I really appreciate it!
SphericalSound wrote:
Tue Sep 29, 2020 8:04 am
funketek wrote:
Mon Sep 28, 2020 9:53 am
For anyone who has successfully programmed the Bluepill for this, did you need to add any #define PIN commands? I have it working as far as the screen reflecting the buttons pushes, but no sound from the OPL2 board. I have independently tested the OPL2 using some arduino sketches and it works fine, but when hooked up to the OR I get no audio. I am not measuring any activity on the "data" pin from the Bluepill at least when using a multimeter, just a constant 4mV. Have confirmed continuity between the actual Atmega chip on the bluepill and the breakout pin.
Also, you shouldnt need to add #defines.

You are using MAC, isnt? Could you try to compile from a PC, just in case? (even if there are other users compiling OK from macs)

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by four_corners » Tue Sep 29, 2020 2:51 pm

SphericalSound wrote:
Tue Sep 29, 2020 8:07 am
four_corners wrote:
Sun Sep 27, 2020 8:12 pm
autodafe wrote:
Sun Sep 27, 2020 3:59 pm
yes, I have used caps on my buttons, the main concern would be the BluePill board (I have used some female headers for it)
also, the screens should be raised a bit...(maybe sing headers again..)
I was looking for some wooden boxes today at the flea market but couldn't find any...
Speaking of the BluePill on headers, I actually would advise anyone building this to use headers for the BluePill, as I actually had some issues with my BluePill and had to desolder it, leading to a giant mess. I ended up tearing some traces, and had to go through the schematic to find all the connections, and then wire a few jumpers. If I would have just put it on female headers, I would have saved about 3-4 hours of headache.
Sure, all peolpe should use sockets. Apart for that obvious reason, it could be that we do an alternative firmware that do it a polyphonic synth, so you just change the bluepill to switch between drummachine and polysynth
Ooh, that would be awesome. The bluepills are so affordable, that would be a great way to switch between firmware without having to reflash it each time.

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by Noodle Twister » Sat Oct 03, 2020 3:12 pm

:guitar: A bluepill polysynth alternative is a great idea!

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by misa » Sat Oct 03, 2020 3:48 pm

four_corners wrote:
Tue Sep 29, 2020 2:51 pm

Ooh, that would be awesome. The bluepills are so affordable, that would be a great way to switch between firmware without having to reflash it each time.
But the opera rotas is so affordable you can just build two and sync the polysynth to the drum machine. ;)

Very portable live setup...!

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by NS4W » Wed Oct 07, 2020 11:42 am

How is the progress with the firmware?

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by SphericalSound » Fri Oct 09, 2020 5:55 pm

NS4W wrote:
Wed Oct 07, 2020 11:42 am
How is the progress with the firmware?
Honestly stucked. Maybe Im open sourcing it in case any other guy(s) wants to keep developing it

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by funketek » Fri Oct 09, 2020 9:39 pm

Programmed Bluepill arrived in the mail today and it works like a charm! :party:

Not sure if I got a bad batch of pills from random seller on aliexpress or some sort of user error on my part (most likely), but I am so happy everything is working now. The strange BPM issue I had on the original chip (the one I tried to program myself) is also gone.

Really great support from Spherical - I appreciate it! :sb:

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by Bjarne » Sat Oct 10, 2020 1:45 am

It’s a great idea to open source the firmware if/when you feel ready for it. That way the life of the device is extended and can continue to progress.
Cheers
SphericalSound wrote:
Fri Oct 09, 2020 5:55 pm
NS4W wrote:
Wed Oct 07, 2020 11:42 am
How is the progress with the firmware?
Honestly stucked. Maybe Im open sourcing it in case any other guy(s) wants to keep developing it

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by Noodle Twister » Mon Oct 12, 2020 9:16 am

SphericalSound wrote:
Fri Oct 09, 2020 5:55 pm
NS4W wrote:
Wed Oct 07, 2020 11:42 am
How is the progress with the firmware?
Honestly stucked. Maybe Im open sourcing it in case any other guy(s) wants to keep developing it
Maybe there are some pointers in here for midi over usb. It works for Arduino leonardo boards and is the way it was implemented on the NS1nanosynth might be worth a look.

https://github.com/rkistner/arcore

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by SphericalSound » Tue Oct 13, 2020 4:19 am

Noodle Twister wrote:
Mon Oct 12, 2020 9:16 am
SphericalSound wrote:
Fri Oct 09, 2020 5:55 pm
NS4W wrote:
Wed Oct 07, 2020 11:42 am
How is the progress with the firmware?
Honestly stucked. Maybe Im open sourcing it in case any other guy(s) wants to keep developing it
Maybe there are some pointers in here for midi over usb. It works for Arduino leonardo boards and is the way it was implemented on the NS1nanosynth might be worth a look.

https://github.com/rkistner/arcore
Great!. I will take a look. Many thanks ;)

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by Faktoidmusic » Wed Oct 21, 2020 8:31 am

I am a bit afraid that this was it with updates for the fine operas rotas?
Will there be any updates coming anytime soon?

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by SphericalSound » Wed Oct 21, 2020 12:21 pm

Im like 2 weeks trying to compile the MIDI libraries to do some test but ATM it dont work. Pretty sure it will be updates at any moment, but I can`t specify when.

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by Faktoidmusic » Wed Oct 21, 2020 11:15 pm

Ah that is good to hear.
I really like the sound and the movement of the OR

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by NS4W » Thu Oct 22, 2020 6:02 am

I'm hoping too... Has a lot of potential, but the machine is very rough functionality wise in its current state. I'm no programmer myself, but maybe open sourcing it would speed up things?

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by nomilian » Fri Nov 27, 2020 7:50 am

I ordered two of the kits in the hopes of giving one to a dear friend, but we both have bigger setups and need the midi syncing for convenience.
I dont know if just open sourcing will work, because we dont know where you are stuck, except that it has to do with the midi library.
Having really high hopes for the maschine and would like to support, although im not too experienced in programming.

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by Faktoidmusic » Sun Dec 06, 2020 1:15 pm

so, some time has passed since the manual is written or anything got updated.
no further notice since weeks and that makes me a bit sad. not the end of the world but it seems one has to accept the actual state of the operas rotas as that's it..
please prove me wrong.
cheers

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by SKYNET_23 » Thu Dec 10, 2020 9:05 pm

Yeah, I would like to see the midi get cool as well, or maybe - is it possible to implement CV CLOCK input? Any idea/ knowledge about that Spherical? Or anybody?

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by SphericalSound » Thu Dec 10, 2020 11:09 pm

I have bad news for you.

After a lot of testing I have discovered that the optocoupler that Opera Rotas uses (4n35) is not fast enought for MIDI transmision.

Somebody did a tutorial using this opto, I followed the hardware and after a lot of testing, yesterday I discovered that the 4n35 is too slow, so it did not work and pretty much it wont have MIDI. Sorry guys, Im the first that I would love to midify it and play with a keyboard. In kind of obsessed with it, but as the machine is set up you cant get it.

In the meantime, if somebody has any idea: maybe bypassing the optocoupler and conecting the midi cable directly to the microcontroller doing some 5v>3.3v voltage division? or something like?

Im all ears

Regarding analog clock input is quite easy with a bit of hacking. Maybe you can use the MIDI in port to do it. I can prepare binaries with this mod, but I havent found a way to distribute it and load into the microcontroller. To date the only way I have found to write the micro is compiling via arduino IDE or Platformio. With the .bin compiled it just dont want to upload via st link nor via USB.

Again, if somebody knows how to do it, Im all ears.

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by Bodo1967 » Fri Dec 11, 2020 3:18 am

SphericalSound wrote:
Thu Dec 10, 2020 11:09 pm
In the meantime, if somebody has any idea: maybe bypassing the optocoupler and conecting the midi cable directly to the microcontroller doing some 5v>3.3v voltage division? or something like?
Perhaps something like bypassing the optocoupler and using a small external interface box based on an 6N137 or similar that accepts MIDI in from a sequencer, and puts out the data via USB so you could connect it directly to the mictrocontroller and even power it from there via the USB jack? Such a box could be really small.
SphericalSound wrote:
Thu Dec 10, 2020 11:09 pm
Regarding analog clock input is quite easy with a bit of hacking. Maybe you can use the MIDI in port to do it.
I can of course only speak for myself, but analog clock would definitely be good as well. Anything that allows the OR to be synced externally will do in the first place :D.

However, I'm afraid I can only add "creative" input but not contribute to writing code :(.
... why buy it for $100 when you can build it yourself for $150?

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by Modulus » Fri Dec 11, 2020 7:29 am

Thanks for your efforts JC

+1, an analog clock input would definitely be a next best option.

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by SphericalSound » Fri Dec 11, 2020 8:12 am

Inexpected good news. I have just received a video from a user that has implemented a second board with other optocoupler (6n138) and it´s responding to midi as he shows it here:



Take it with a grain of salt, as it needs a separate PCB, new firmware and he says that when there´s a lot of messages the midi goes slow down. He says he´s rewritting a good chunk of code. I guess now is a question of optimizing code for it to go on time. Let´s see how it develops.

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by SphericalSound » Fri Dec 11, 2020 8:26 am

Modulus wrote:
Fri Dec 11, 2020 7:29 am
Thanks for your efforts JC

+1, an analog clock input would definitely be a next best option.
When I have the new MIDI firmware I will try to implement "analog clock in" in the current MIDI IN port. I guess should be doable without hacking the hardware side but I have to check it first, so dont hold your breath. All this could take some weeks if it even ends working.

I still dont know how to do the upload of the new firmware, let´s wait for someone to find a way to do it easily for the end user

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by Bodo1967 » Fri Dec 11, 2020 8:35 am

SphericalSound wrote:
Fri Dec 11, 2020 8:26 am
When I have the new MIDI firmware I will try to implement "analog clock in" in the current MIDI IN port. I guess should be doable without hacking the hardware side
That would be awesome! And a big thank you for your efforts also from my side!
... why buy it for $100 when you can build it yourself for $150?

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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by Bjarne » Fri Dec 11, 2020 3:48 pm

MIDI will be great even if it's done via a separate board.
Cheers

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