Befaco VCMC DIY - boot issues

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mOBiTh
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Befaco VCMC DIY - boot issues

Post by mOBiTh » Tue Nov 19, 2019 4:17 pm

Hey guys anyone out there built a VCMC yet?

I put mine together a couple of weeks ago but had some issues.

The first screen I got was a dud so that was replaced.

The second screen only comes on about 50% of the time - it's pretty random whether or not it does. When it doesn't come on, the T3.2 still seems to be working normally* and the faders generate MIDI

*The second remaining issue is that sometimes the machine boots up without fader2 operational (also about 50% of the time, but not the same 50% as the screen not lighting up :hihi: ) - in this state everything else is working normally.

Bit weird!

When it boots up normally everything works perfectly :hmm:

Any thoughts?

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akirasrebirth
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Re: Befaco VCMC DIY - boot issues

Post by akirasrebirth » Tue Dec 24, 2019 3:47 am

Hey,

I had the same problem with a built VCMC module. The nice guys at Befaco sent me a new one. The old module had boot problems in 50% of the cases and the new one only once in a while. If the module doesn't turn on, one of the 5v voltage regulators gets very hot, like there was a short. My case has a PSU3 power supply ... I tried also a case with a linear Doepfer power supply, but the problem persists. I also changed the voltage regulator and re-flowed some solder joints with no success.

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Re: Befaco VCMC DIY - boot issues

Post by eewee » Thu Jan 02, 2020 12:30 pm

Had the same problem with a DIY VCMC that worked fine all through the build and initial tests (using a Doepfer beauty case as power supply). When finished, I put it in my main case (a Doepfer PSU3 based LC6) where it also worked fine a few days ago. Today I power up that case again, and the VCMC just sits there, blank screen. Switched power on a few times, and it would come up half of the time. Moved it back to the beauty case, and it worked fine all over again.

Then I remembered that I had the same problem before with a Radio Music, which is also Teensy based. The (100% so far) solution there was to delay power up to avoid the initial power surge from other modules, allowing the Teensy to boot up on a stable voltage. I used a WMD Soft Start thingie for that. I now moved the Soft Start behind the VCMC, and so far, no problems yet. Could be superstition, of course. Time will tell.

Maybe somebody from Befaco could chime in, and confirm or deny my theory?
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Re: Befaco VCMC DIY - boot issues

Post by Befacosynth » Wed Jan 08, 2020 9:47 am

Hi all! Sorry for not being too present over here..... pliz drop us a mail if facing troubles. For this module in particular pliz mail manu@befaco.org

We have been facing troubles with a batch of screens, so some cases of booting problems were solved by changing the screen.
eewee wrote:
Thu Jan 02, 2020 12:30 pm

Then I remembered that I had the same problem before with a Radio Music, which is also Teensy based. The (100% so far) solution there was to delay power up to avoid the initial power surge from other modules, allowing the Teensy to boot up on a stable voltage. I used a WMD Soft Start thingie for that. I now moved the Soft Start behind the VCMC, and so far, no problems yet. Could be superstition, of course. Time will tell.
This is an interesting theory. There is another user that faced this booting issue in one of his cases, and changing to a less loaded case solved the situation. So it might make sense this inrush current possible scenario.
I need to setup a system that make it not load and replicate the situation. Then try to find a solution :? :? :?
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Re: Befaco VCMC DIY - boot issues

Post by eewee » Wed Jan 08, 2020 12:48 pm

Hey Manu,

I had in mind to send you an email about this thread, but was waiting a few days, to avoid breathing down your neck :-) You beat me to it.

I doubt you can fix it in software (your Teensy is not running when this happens), but if you're looking for hardware changes, adding a MIC803 seems to be a common solution. There's a thread (viewtopic.php?f=16&t=223314) where this is discussed and apparently this was also done in later O_C hardware versions.

Let me know if your solution is backportable!
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Re: Befaco VCMC DIY - boot issues

Post by Befacosynth » Mon Jan 13, 2020 11:12 am

Solution from the hardware perspective is not happening in the near future..... need to do a hardware revision and we have plenty of stock.

There is a chance to make a lil shield to add the MIC803 to the exp port + one cable soldered. anyone interested to try it? It might involve etching a lil board and solder a bit. :)
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Re: Befaco VCMC DIY - boot issues

Post by eewee » Mon Jan 13, 2020 11:44 am

Etching is out of (my) bounds, at least for the moment, I'm afraid. Soldering's no problem.
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Re: Befaco VCMC DIY - boot issues

Post by Befacosynth » Tue Feb 18, 2020 1:47 pm

We have been silent over here but not still about the issue! So i 'm glad to come with (good?) news.

Got a response from Paul Stoffregen (Mr. Teensy himself) about this issue and seems to be related to the RTC rather than a brown out issue.So he instructed to disable it (as VCMC does not use it) and seems to be working!

Attached a beta version of the new firmware with RTC disabled. Please try it and report back!!
VCMC_1_1_RTC_OUT.zip
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Re: Befaco VCMC DIY - boot issues

Post by eewee » Tue Feb 18, 2020 4:59 pm

Thank you!

I won't be able to test it until the weekend, though.
But already a preparatory question: when I upgrade the teensy, should/must/need I power the module from the Eurorack power bus (I don't remember cutting any 5V pad)? And when you say USB port, do you mean the front panel one, or the one on the teensy?


ps: I did some extra google'ing, and this thread on the PJRC forum seems to carry all the right keywords: https://forum.pjrc.com/threads/56541-Te ... ot-booting
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Re: Befaco VCMC DIY - boot issues

Post by thefishman77 » Sat Feb 22, 2020 3:05 pm

I too was having startup issues and thought it had to do with power. I just found this thread. I tried the 1.1 firmware and so far so good! I've restarted my system several times and the VCMC has turned on successfully each time. Hopefully it continues. Thanks for the help!
-Adam
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Re: Befaco VCMC DIY - boot issues

Post by Befacosynth » Sun Feb 23, 2020 7:27 am

thefishman77 wrote:
Sat Feb 22, 2020 3:05 pm
I too was having startup issues and thought it had to do with power. I just found this thread. I tried the 1.1 firmware and so far so good! I've restarted my system several times and the VCMC has turned on successfully each time. Hopefully it continues. Thanks for the help!
-Adam
www.thesolutionmusic.com
Great news indeed!!! We will be publishing this new code pretty soon!!
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Re: Befaco VCMC DIY - boot issues

Post by eewee » Sun Feb 23, 2020 10:44 am

yep - success here as well. In the same spot where it would fail to boot reliably before, it now comes up in v1.1 every time I power up the case. And without the WMD Soft Start, of course.

And to answer my own questions: you can power the teensy from USB when upgrading (at least in the configuration my teensy came with in the DIY kit), using just the micro usb connector on the teensy board.

:tu:
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Re: Befaco VCMC DIY - boot issues

Post by trigger303 » Mon Feb 24, 2020 8:31 pm

Tried VCMC_1_1_RTC_OUT firmware.
Boot issue is solved!

But now, CV input on CH1 get unstable. It's rapidly fluttering backward and forward between C# and D.
It doesn't occur in v1.0 firmware.

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Re: Befaco VCMC DIY - boot issues

Post by Befacosynth » Wed Mar 11, 2020 10:59 am

trigger303 wrote:
Mon Feb 24, 2020 8:31 pm
Tried VCMC_1_1_RTC_OUT firmware.
Boot issue is solved!

But now, CV input on CH1 get unstable. It's rapidly fluttering backward and forward between C# and D.
It doesn't occur in v1.0 firmware.
Looks like a callibration issue. Callibrate the channel and check!
www.befaco.org
support((at))befaco.org

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Re: Befaco VCMC DIY - boot issues

Post by trigger303 » Thu Mar 19, 2020 7:08 pm

Befacosynth wrote:
Wed Mar 11, 2020 10:59 am
trigger303 wrote:
Mon Feb 24, 2020 8:31 pm
Tried VCMC_1_1_RTC_OUT firmware.
Boot issue is solved!

But now, CV input on CH1 get unstable. It's rapidly fluttering backward and forward between C# and D.
It doesn't occur in v1.0 firmware.
Looks like a callibration issue. Callibrate the channel and check!

Thanks for comment, sorry for late reply.

I callibrated CV input but it didn't help. CH1 CV still remains drifting.
When I go back to v1.0, it doesn't occur.

I know v1.1 is not official release currently, so I'll wait for next release! Thanks.

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Re: Befaco VCMC DIY - boot issues

Post by Befacosynth » Fri Mar 20, 2020 6:48 am

Thanks for the info. will take a look on this issue this weekend!

in the meantime, do you need a v1 with RTC removed?
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Re: Befaco VCMC DIY - boot issues

Post by trigger303 » Tue Mar 24, 2020 1:43 am

Befacosynth wrote:
Fri Mar 20, 2020 6:48 am

in the meantime, do you need a v1 with RTC removed?
No, but thank you!
I'm enoughly having fun with current v1.0 firmware.
Even if a problem occurs, rebooting makes the module work correctly.

Many thanks!

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Re: Befaco VCMC DIY - boot issues

Post by Befacosynth » Wed Mar 25, 2020 1:12 pm

Uploaded v1 with RTC removed:

https://github.com/Befaco/VCMC

No we are at v1.0.1 :)

Hope to have v 1.1 ready soon!
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Re: Befaco VCMC DIY - boot issues

Post by nmihalevich » Tue Mar 31, 2020 11:29 am

trigger303 wrote:
Thu Mar 19, 2020 7:08 pm
Befacosynth wrote:
Wed Mar 11, 2020 10:59 am
trigger303 wrote:
Mon Feb 24, 2020 8:31 pm
Tried VCMC_1_1_RTC_OUT firmware.
Boot issue is solved!

But now, CV input on CH1 get unstable. It's rapidly fluttering backward and forward between C# and D.
It doesn't occur in v1.0 firmware.
Looks like a callibration issue. Callibrate the channel and check!

Thanks for comment, sorry for late reply.

I callibrated CV input but it didn't help. CH1 CV still remains drifting.
When I go back to v1.0, it doesn't occur.

I know v1.1 is not official release currently, so I'll wait for next release! Thanks.

Having the same CV fluttering problem with my VCMC. I've calibrated many times and it seems to just return. Is the unit loosing calibration upon each power cycle?

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Re: Befaco VCMC DIY - boot issues

Post by Befacosynth » Wed Apr 01, 2020 7:03 am

nmihalevich wrote:
Tue Mar 31, 2020 11:29 am

Having the same CV fluttering problem with my VCMC. I've calibrated many times and it seems to just return. Is the unit loosing calibration upon each power cycle?
Weird indeed. Data structure has changed so most likely you need to re-calibrate.
Can you please compare bahaviorfrom the firmware i posted here with the new firmware I uploaded to github?
Both have RTC removed but one is a v1 and the other is a v1.1 Beta.
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Re: Befaco VCMC DIY - boot issues

Post by nmihalevich » Thu Apr 02, 2020 10:24 am

Befacosynth wrote:
Wed Apr 01, 2020 7:03 am
nmihalevich wrote:
Tue Mar 31, 2020 11:29 am

Having the same CV fluttering problem with my VCMC. I've calibrated many times and it seems to just return. Is the unit loosing calibration upon each power cycle?
Weird indeed. Data structure has changed so most likely you need to re-calibrate.
Can you please compare bahaviorfrom the firmware i posted here with the new firmware I uploaded to github?
Both have RTC removed but one is a v1 and the other is a v1.1 Beta.
Both seem to act the same for me. Aux A has always fluttered. Figured it was a build prob, with mind, since it's a DIY. Other than that channel, I don't have any fluttering going on.

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