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 » Mon Sep 14, 2020 4:49 pm

NS4W wrote:
Mon Sep 14, 2020 3:54 pm
Been playing with mine today - fun sounds but I'm looking forward to firmware updates!

Would be great if RND didnt affect locked channels.

Exit EDIT mode allways leave steps on the key press you use to leave the mode with, so I have to press 12 for example before exiting to another channel if I don't want a step there - a bit tedious!
Yeah, you are totally right. This and a lot of other features are planned to the next firmware update.

You will be able to random partially or fully each channel that you want instead of all parameters at the same time between other things...

Please, go getting one of the stlink v2 gadget (around 3USD in ebay) to update it when ready if you dont have one yet!

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

Post by NS4W » Tue Sep 15, 2020 12:52 am

SphericalSound wrote:
Mon Sep 14, 2020 4:49 pm

Please, go getting one of the stlink v2 gadget (around 3USD in ebay) to update it when ready if you dont have one yet!

Image
I got one waiting! 🤗🤗🤗

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

Post by Bjarne » Tue Sep 15, 2020 1:52 am

Great!

I bought a partial kit a couple of weeks ago and wonder if it is possible to get hold of the firmware? Eventually I’d like to play around with it and possibly do some modifications.

Cheers
SphericalSound wrote:
Mon Sep 14, 2020 4:49 pm

Yeah, you are totally right. This and a lot of other features are planned to the next firmware update.

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

Post by SphericalSound » Tue Sep 15, 2020 2:31 am

Bjarne wrote:
Tue Sep 15, 2020 1:52 am
Great!

I bought a partial kit a couple of weeks ago and wonder if it is possible to get hold of the firmware? Eventually I’d like to play around with it and possibly do some modifications.

Cheers
SphericalSound wrote:
Mon Sep 14, 2020 4:49 pm

Yeah, you are totally right. This and a lot of other features are planned to the next firmware update.
Sure,

dm your mail. I will send you it.

=D

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

Post by Bodo1967 » Tue Sep 15, 2020 2:31 am

SphericalSound wrote:
Mon Sep 14, 2020 4:49 pm
Yeah, you are totally right. This and a lot of other features are planned to the next firmware update.
[mantra chant] Clock-in, clock-in, clock-in! [/mantra chant] :mrgreen:
SphericalSound wrote:
Mon Sep 14, 2020 4:49 pm
Please, go getting one of the stlink v2 gadget
Mine is lying beside the OR and waiting for its first job...

[mantra chant] Clock-in, clock-in, clock-in! [/mantra chant]

8-) :mrgreen:
... 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 autodafe » Tue Sep 15, 2020 6:02 am

I just received a pre-programmed Blue PIll and (of course) it works! Finally!!! :sb:


(please, we need a 100% working procedure to update the firmware in the future using the St-Link and and .hex file...I don't want to "break" the current working board, so I have a couple of Blue PIlls replacements...)

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

Post by autodafe » Tue Sep 15, 2020 6:17 pm

I just made a quick demo-jam using the Opera Rotas in sync with my LXR (using Clock Out on the OR)
This thing is wicked!!!


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

Post by Noodle Twister » Sun Sep 20, 2020 11:41 am

opera_rotas1.png
Lovely. What a brilliant machine. Love it!
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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by Mattbartlett303 » Mon Sep 21, 2020 7:08 am

Just finished building mine, it sounds great.

just a warning to others - Don't push the random button if you are using headphones, the volume is seriously unpredictable. (Probably worth running the output into a limiter if you plan on experimenting with the random mode)

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

Post by SphericalSound » Wed Sep 23, 2020 3:33 am

IMG_20200922_125141.jpg
This is from Pablo a Spanish user. Too beauty not to share
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Last edited by SphericalSound on Wed Sep 23, 2020 12:00 pm, edited 1 time in total.

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

Post by Bjarne » Wed Sep 23, 2020 5:33 am

Nice! Do you know where those buttons are from?
B
SphericalSound wrote:
Wed Sep 23, 2020 3:33 am
This is from Pablo and Spanish user. Too beauty not to share

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

Post by SphericalSound » Wed Sep 23, 2020 11:59 am

Bjarne wrote:
Wed Sep 23, 2020 5:33 am
Nice! Do you know where those buttons are from?
B
SphericalSound wrote:
Wed Sep 23, 2020 3:33 am
This is from Pablo and Spanish user. Too beauty not to share
Yeah, he says buttons and knobs are from Tayda

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

Post by four_corners » Wed Sep 23, 2020 10:23 pm

Would be great to get future firmware updates through this post!

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

Post by Faktoidmusic » Wed Sep 23, 2020 11:34 pm

I have this wonderful machine too and it is a joy to play with it.
As of right now there is no midi sync?
Did I get this right?
And just in case a FW update arrives, is there already an update procedure?
Thank you for your replies :)

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

Post by SKYNET_23 » Thu Sep 24, 2020 11:41 am

Yes, yes, and no- not yet. Spherical has promised these features in future updates, there are a bunch of interested users, and plans for an eventual open source-ing of the firmware so it will happen sooner or later.... Look back thru the thread, there is a hardware programmer for the blue pill that is needed to do the updating.

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

Post by four_corners » Thu Sep 24, 2020 12:46 pm

SKYNET_23 wrote:
Thu Sep 24, 2020 11:41 am
Yes, yes, and no- not yet. Spherical has promised these features in future updates, there are a bunch of interested users, and plans for an eventual open source-ing of the firmware so it will happen sooner or later.... Look back thru the thread, there is a hardware programmer for the blue pill that is needed to do the updating.
Open sourcing the firmware could be very interesting, as I think there are lots of implementations of this machine that could work.

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

Post by autodafe » Sun Sep 27, 2020 5:55 am

is someone able to design a case for the OR? Acrylic or whatever, it would be handy ;-)

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

Post by four_corners » Sun Sep 27, 2020 3:35 pm

autodafe wrote:
Sun Sep 27, 2020 5:55 am
is someone able to design a case for the OR? Acrylic or whatever, it would be handy ;-)
I can't confirm this, but some of the components may need to be tweaked from the main BOM if a case is made, as a lot of the components are at varying heights. For example, you may need taller push buttons, or push buttons that accept button caps.

Or, you can just make larger cutouts for some of the areas...


I agree though, it would be nice to protect everything a bit more. I still use lead solder, so I also am not the biggest fan of diy synths that allow me to still touch a bunch of lead when moving the synth around or playing it.

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

Post by autodafe » 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...

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

Post by four_corners » 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.

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

Post by funketek » 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.

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

Post by four_corners » Mon Sep 28, 2020 1:48 pm

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.
Is the lack of audio the only issue you've noticed, or does anything else seem odd? Might be worth looking at the schematic and check continuity backwards from the audio jack to make sure you have a solid connection to the circuit?

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

Post by funketek » Mon Sep 28, 2020 2:55 pm

Yes, the other weird issue I noticed was the shift+volume knob does alter the BPM, but only in a range of 70-92 bpm. The coding says it should go from 70-160bpm. Unfortunately, while I socketed the screen and Bluepill, I did not on the multiplexers. I de-soldered the U3 chip with hot air and put in a new one, but same BPM issue (although the chip was from the same Aliexpress seller, so maybe they're all bad?) I did check all of the pots and the voltages at the pot does match the corresponding pin on the multiplexer breakout. Multiple button presses, like edit+channel seems to work fine and the LEDs change to the dedicated grid when editing as you would expect.

I had previously hooked up the OPL board to an Arduino Uno and loaded some of the OPL library sketches and I got audio from the OPL, so I feel like that piece is good. I have programmed plenty of other MCUs before, but this one is giving me issues, so I am trying to see if I screwed up the programming somehow. Have also reached out to Juan Carlos about just buying a pre-programmed Bluepill (which I should have done in the first place, apparently!) - just feels like I am very close, but overlooking something..

I guess, my question is - I would expect the data pin on the Bluepill to show some activity while the sequencer is running, but I am not picking up anything on the meter. Is it the Data pin outgoing only, or is it bi-directional?

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

Post by SphericalSound » Tue Sep 29, 2020 8:02 am

The data pin should deffo be showing activity. I would say your build is working but somehow the bluepill is not correctly programmed. The OPL2 is 100% ok.

All the pins on the OPL2 are read only, none goes back to the microcontroller

Also the pots only doing half of the travel is weird. To me it seems like you have some short anywhere or a wrong value resistor, maybe? Could you read the voltage at the pots pins 1 and 3? Should be GND and 3.3V. Read in various of them on different rows: for example pot 1, 5, 8 and 13

I guess you should order a programmed blupill. If it does not fix it, you can ship it back and I´ll refund you it, so at least we sort this out

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

Post by SphericalSound » 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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