OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

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Bodo1967
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Re: OPERA ROTAS, a DIY mutant drum machine

Post by Bodo1967 » Tue Sep 01, 2020 12:44 pm

autodafe wrote:
Tue Sep 01, 2020 11:56 am
Any idea on what to troubleshoot next? maybe something else got fried by inverting the polarity of the screen ??
I consider it likely that you have to replace the display. According to Juan the OR won't boot without the display:
SphericalSound wrote:
Tue Aug 11, 2020 4:27 pm
It needs the screen to boot, tho :tu:
I really hope that this is all you need to replace and you'll get yours to work soon - fingers crossed!
... 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

Post by autodafe » Tue Sep 01, 2020 1:45 pm

ah OK I didn't know it would not boot without the display connected.
I think I have another one I can teporarily take from another module I have...or maybe Amazon has one on Prime ready for tomorrow...
thanks

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by SphericalSound » Wed Sep 02, 2020 6:34 am

autodafe wrote:
Tue Sep 01, 2020 11:56 am
I finished building mine, after lots of struggle I (apparently) managed to program the Blue PIll

Then I switched the OP on and noticed that the screen was getting really really hot, at one point it became red and something burned, i presume...
I measured -3.3 Volts on the screen VCC/GND and then realized that VCC and GND on my display board were INVERTED !!! :mad:


Image

I cut the headers on the screen and connected a couple of wires in the correct way. now the screen has the correct voltage (+3.3V), but I believe it's fuc*ed...
The unit doesn't seem to work. No noise from it, no leds light up, buttons do nothng as well as pots...
I guess that something shoule light up even if the screen is gone...

Any idea on what to troubleshoot next? maybe something else got fried by inverting the polarity of the screen ??
You prob fried the screen. The microcontroller waits for the screen to say "Im here and ready to work". As the screen never send this message, the micro never boot and keeps waiting the ready message from the screen. So you need a new screen to even test if the micro was correctly programmed

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by Modulus » Wed Sep 02, 2020 10:12 am

Due to time issues, I went ahead and picked up a prebuilt Opera Rotas and am selling my full DIY kit w/ OPL2 board at a discount in the US. viewtopic.php?f=74&t=236926

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by autodafe » Wed Sep 02, 2020 12:49 pm

:cry: :cry: nope, screen replaced, still no sign of life....

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by misa » Wed Sep 02, 2020 2:32 pm

I built mine and it works and sounds nicely.

When I came back to it tonight, the screen stays black, the unit seems to work as it should though. Is there a way to "wake up" the screen? powercycling doesn't change anything. There is sound and all functions seem to behave normally.

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by SphericalSound » Fri Sep 04, 2020 8:18 am

autodafe wrote:
Wed Sep 02, 2020 12:49 pm
:cry: :cry: nope, screen replaced, still no sign of life....
It seems you failed programming it. You have a new microcontroller on the way. It´s going to work, word!

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by SphericalSound » Fri Sep 04, 2020 8:21 am

misa wrote:
Wed Sep 02, 2020 2:32 pm
I built mine and it works and sounds nicely.

When I came back to it tonight, the screen stays black, the unit seems to work as it should though. Is there a way to "wake up" the screen? powercycling doesn't change anything. There is sound and all functions seem to behave normally.
As I told you it seems the screen has gone kaput. Replacing it should solve it. It will be working with the new one. In the menatime you can do some unescreened noises.

The first proto was with no screen and you can do super cool jams that way too. Go for it

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by autodafe » Fri Sep 04, 2020 10:52 am

SphericalSound wrote:
Fri Sep 04, 2020 8:18 am
It seems you failed programming it. You have a new microcontroller on the way. It´s going to work, word!
I really hope so. But then , you need to make an idiot-proof guide on how to program that STM32...for future updates to the Firmware...
(programming looked OK, no errors, but I have some doubts about memry addresses 0x08000000 for bootloader and 0x08002000 for the firmware)

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by Bodo1967 » Mon Sep 07, 2020 6:31 am

I gave mine some nice knobs on the weekend. The picture is a detail from the original Ebay offer into which I drew how I trimmed them:
s-l1600.jpg
Source for the original picture

The plastic part inside in reality was pushed in deeper, and I couldn't pull it out. That meant it was too deep in for the pot shaft to reach it. So I carefully cut the edges of the aluminum pots with my proxxon and one of these:
818pLiLY63L__SL1500_.jpg
Source for the picture
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... 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

Post by misa » Mon Sep 07, 2020 9:31 am

SphericalSound wrote:
Fri Sep 04, 2020 8:21 am
misa wrote:
Wed Sep 02, 2020 2:32 pm
I built mine and it works and sounds nicely.

When I came back to it tonight, the screen stays black, the unit seems to work as it should though. Is there a way to "wake up" the screen? powercycling doesn't change anything. There is sound and all functions seem to behave normally.
As I told you it seems the screen has gone kaput. Replacing it should solve it. It will be working with the new one. In the menatime you can do some unescreened noises.

The first proto was with no screen and you can do super cool jams that way too. Go for it

Thank you for your help. I have been recording many clicks and beats without the screen and I love it. With screen it‘s nicer, but as long as it sounds (and RND works...;) I‘m ok..;)

kainiggemann.bandcamp.com
anterasa.bandcamp.com
gratofficial.bandcamp.com
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Re: OPERA ROTAS, a DIY mutant drum machine

Post by yan6 » Wed Sep 09, 2020 7:10 pm

I got mine up and running today. Is there any shortcut way to clear all the patterns across the 8 channels. And could you explain the volume controls. It appears as though the center is the lowest volume while either left or right is full volume
15996965800355232937209823669742.jpg
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Re: OPERA ROTAS, a DIY mutant drum machine

Post by misa » Fri Sep 11, 2020 5:49 am

PSA: are you using sockets to connect the display, Blue pill, OPL and multiplexers?

I have to exchange a faulty screen and it's quite complicated now without them.

so I learned: use sockets. especially if there is a board that makes access to the solder pads of other components difficult...

(AKA: PLAN AHEAD, SILLY!)

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by SphericalSound » Fri Sep 11, 2020 9:54 am

Bodo1967 wrote:
Mon Sep 07, 2020 6:31 am
I gave mine some nice knobs on the weekend. The picture is a detail from the original Ebay offer into which I drew how I trimmed them:

s-l1600.jpg
Source for the original picture

The plastic part inside in reality was pushed in deeper, and I couldn't pull it out. That meant it was too deep in for the pot shaft to reach it. So I carefully cut the edges of the aluminum pots with my proxxon and one of these:

818pLiLY63L__SL1500_.jpg
Source for the picture
Instaed of cutting the base, what I do is insert little paper balls between the pot and the knob, so the knob sits upper and not touch the base. Any paper works

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by SphericalSound » Fri Sep 11, 2020 9:56 am

misa wrote:
Mon Sep 07, 2020 9:31 am
SphericalSound wrote:
Fri Sep 04, 2020 8:21 am
misa wrote:
Wed Sep 02, 2020 2:32 pm
I built mine and it works and sounds nicely.

When I came back to it tonight, the screen stays black, the unit seems to work as it should though. Is there a way to "wake up" the screen? powercycling doesn't change anything. There is sound and all functions seem to behave normally.
As I told you it seems the screen has gone kaput. Replacing it should solve it. It will be working with the new one. In the menatime you can do some unescreened noises.

The first proto was with no screen and you can do super cool jams that way too. Go for it

Thank you for your help. I have been recording many clicks and beats without the screen and I love it. With screen it‘s nicer, but as long as it sounds (and RND works...;) I‘m ok..;)
Great!. With the screen is 10x more fun =D. Hoping you get it. IS quite easy to desolder: just put a resistor leg touching the four pins at the same time, while you apply the hot at the center pins. When all are liquid, remove the screen with tweezers and then put the new one.

Obviously with sockets is easier, but with some practice is doable
Last edited by SphericalSound on Fri Sep 11, 2020 10:01 am, edited 1 time in total.

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by SphericalSound » Fri Sep 11, 2020 9:59 am

yan6 wrote:
Wed Sep 09, 2020 7:10 pm
I got mine up and running today. Is there any shortcut way to clear all the patterns across the 8 channels. And could you explain the volume controls. It appears as though the center is the lowest volume while either left or right is full volume

15996965800355232937209823669742.jpg
No direct way to clear all patterns. I will include a blank pattern in the next firmware. Volume has a bug where at the most left is top, so you better put it abit over zero to get zero. The rest of the travel is as you expected. I´ll be addressing this bug too.

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

Post by yan6 » Fri Sep 11, 2020 10:26 am

I'm also curious how the base sounds get generated. In some patterns I hear sounds that dont seem atainable from other sounds. Said another way I hear something like a snare sound and in another randomisation I hear heavy FM sounds. It doesnt seem any amount of knob twiddling will turn the snare into the FM sound. Is there a bit pattern coming from the microcontroller that predetermines the sounds starting point.

Also, when I hit the randomize button, I for the most part just got noise sounds?

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by Bodo1967 » Fri Sep 11, 2020 11:14 am

SphericalSound wrote:
Fri Sep 11, 2020 9:54 am
Instaed of cutting the base, what I do is insert little paper balls between the pot and the knob, so the knob sits upper and not touch the base. Any paper works
That wouldn't have helped here since the plastic inner part of the knob (where the knurled part is) then wouldn't even have touched the (short!) pot shaft ;).
... 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 SphericalSound » Fri Sep 11, 2020 7:41 pm

yan6 wrote:
Fri Sep 11, 2020 10:26 am
I'm also curious how the base sounds get generated. In some patterns I hear sounds that dont seem atainable from other sounds. Said another way I hear something like a snare sound and in another randomisation I hear heavy FM sounds. It doesnt seem any amount of knob twiddling will turn the snare into the FM sound. Is there a bit pattern coming from the microcontroller that predetermines the sounds starting point.

Also, when I hit the randomize button, I for the most part just got noise sounds?
Great questions. Channel 6 is the kick. It´s predefined in the yamaha hardware to always sound like a kick. Chanel 7 is snare and 8 is the charles/cymball. Those three are specialized in that sounds, and you can get that sounds only in that 3 channels. The rest are 100% free customizable.

The random actually randomizes all channels and all parameters, so its a bit too heavy and brutal, yepp, but from time to time, you find pearls too. =D

In the next firmware I will let it randomize partially and only based in the previous preset and also in the channel that you choose, so you gain all the finesse and control of it. Theres also an experiemtal mode where you subtly randomize all the params of the current song and it opens the door to massive happy accidents...

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by misa » Sat Sep 12, 2020 3:31 pm

SphericalSound wrote:
Fri Sep 11, 2020 9:56 am

Great!. With the screen is 10x more fun =D. Hoping you get it. IS quite easy to desolder: just put a resistor leg touching the four pins at the same time, while you apply the hot at the center pins. When all are liquid, remove the screen with tweezers and then put the new one.

Obviously with sockets is easier, but with some practice is doable

Thank you, this advice is like Magic!

I had the screen on briefly at first, then it died. I think I will get it with the screen..!

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anterasa.bandcamp.com
gratofficial.bandcamp.com
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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by aseaman » Sun Sep 13, 2020 10:16 am

So I finished building this the other day however there is no output from either the audio jack or the clock output. The LEDs and the screen light up, I can use the various switches to navigate through the different modes, edit the different channels, change the BPM, etc. but no output. I verified that the OPL board is getting 5v and the various ICs appear to be oriented correctly. Adjusting the trimmer on the OPL board does not have any noticeable effect either. Below are some images of the various boards. Any additional advice would be greatly appreciated!
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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by Noodle Twister » Sun Sep 13, 2020 10:39 am

opl2_1.jpg
Hi aseaman, it appears that your electrolytic capacitors on the OPL2 board are orientated the wrong way around. You will need to desolder them and replace them with the grey negative stripe of both electrolytics facing the right side of the board. The pic above shows how they should be.
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Re: OPERA ROTAS, a DIY mutant drum machine BUILD THREAD

Post by aseaman » Mon Sep 14, 2020 8:44 am

:doh: You're right, the caps for the OPL board were backwards. I flipped those but still no output. There's only one electrolytic cap on the main board and I verified that is oriented correctly (negative side facing the blue pill).

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

Post by NS4W » 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!

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

Post by SphericalSound » Mon Sep 14, 2020 4:45 pm

aseaman wrote:
Mon Sep 14, 2020 8:44 am
:doh: You're right, the caps for the OPL board were backwards. I flipped those but still no output. There's only one electrolytic cap on the main board and I verified that is oriented correctly (negative side facing the blue pill).
Everything seems OK from the photos (good eye Noodle Twister). You should not just flip the caps, but put new ones as that ones are probably damaged.

If it still dont work, I would reflow the tracks and solder points that connects the opl2 to the bluepill.

If that keeps not working I would reflow the whole PCB. And if it still not works, I would order a new OPL2 as maybe you fried it. (I dont think so but it´s not impossible either)

You can check if it´s fried connecting it to an arduino and uploading the basic opl2 drum example to that arduino. It´s all explained in the opl2 github

https://github.com/DhrBaksteen/ArduinoOPL2

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