Okai, I have all my jack sockets mixed up! (signal and ground) -.-
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Now I have some sound that changes when I turn the encoder, but there is no reaction from any of the potentiometers or input jacksā¦
I am trying now to measure where things are getting lost.
Starting with the ācolorā potentiometer. Aref is correct (-10V and I can also measure the change of V at the middle leg, but after that I only measure 0V wherever I tryā¦ I think for the inverted input this is expected at the opamp (pin 6 of the MCP6004) but there should be something at the output! The MCP6006 does have GND and 3.3V at the right pinsā¦ what else can I check?
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Just found out that I have a short between pin 6 and 7 of IC7Bā¦ wondering how that can be, because there are only the resistor (R26) and the capacitor (C14)ā¦
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No time to look at the full schematics, but shouldnāt it have a dual supply? (since theyāre both used as inverting amplifiers).
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Good question, the TL074 has the usual + and -12V but the MCP6004 notā¦ but it is a tested design, I thinkā¦ (only thing I changed was converting from eagle to kicad and move around some labels).
nooo! I used 49.9 ohm instead of 49.9k!! 
So stupid!!
Could I replace them with 47k? need to calculateā¦
Edit: Also the 24.9k are only 24.9 ohmā¦ 
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The odd values are there to get reasonably precise 2:1 and 4:1 ratios (the first opamp divides by four, the second multiplies by two). You can use 100k resistors in parallel to get precise values, but that gets a bit unwieldy for the 25k ones I guess.
I missed that the first opamp was a TL074, btw; the MCP6004 is rail-to-rail amplifier in an inverting 2Ć configuration, so it can handle negative voltages from the first opamp + R38 (summed over R31 and R32).
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Did you switch the jumper position on the blue pill? I did a SoundForce module using an STM32 with no need for a boot loader. I thought it was only needed if you want to communicate with it via USB. But Iām quite inexperienced with microcontrollers.
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Yeah, I tried that a lot! I could also program it when both jumpers are in 0 position (operation mode)ā¦ my guess is that you need to set it to system memory boot (BOOT0 to 1) in order to program it via UART?
I am also a beginner with this, but as I understand it, if you select user flash (both jumpers on 0), the stm32 boots and looks at the user flash location (0x0800 0000) and runs the code that is there. Which is fine if your program starts there! But the braids code starts at address 0x0800 4000 (this is fixed in the hex file). so when the stm32 boots it looks at 0x0800 0000 and finds nothing, so it does nothing. You need something to point it to the beginning of your program. This is the (simplest) task of the bootloader Why use it and not just move the main code to 0x0800 0000? The bootloader can do additional things, like in the braids case update the firmware (you need to set the knobs to certain positions and then power on the braids with the encoder pressed, then play the new firmware as a soundfile in the FM-in).
So in your case, maybe the bootloader was included in the hexfile or maybe it did not have a āspecialā bootloader and the program just began at 0x0800 0000?
Probably someone with more knowledge about microcontrollers should read this and tell us whatās really happening, but to me this made sense, somehow 
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sorry Iām very bad at reading and pretty late to the party on this one! I gotta apologise I havent actually had proper internet this past month resulting in only going on the internet to do whats needed! so I havent been on the forum a massive amount! but this is cool! how is it going? is anyone having any luck with the THT version??? I was going to do one but alas havent got round to it! excited if someone comes up with one!!!
one request if possible if someone is doing it. for the coarse tune knob. on my braids I have a switch that selects between a preset potentiometer around the back and the actual knob. this means you can tune it to a definite note around the back and the coarse tune is disconnected. meaning you dont spend ages tuning at gigs!!! but the switch means you can still use the coarse tune too if you want.
Also, not sure how everyone is with the code. but having the octave thats in the menu screen on a knob was another addition I was gunna try and implement, but that would mean coding, and I have never modded stuff for stm chips.
ill be eagerly following this project 
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Itās coming along! I am still waiting for the correct resistors, because I am dumb and have missed the k when ordering, so I got 49,9 ohm instead of kohm 
Hope they turn up tomorrow, because I will be on holiday for two weeks after that!
Good to know about the switch! Might add this when I get it working!
So far I have only downloaded the compiled code and not looked at it, also maybe later, first I want it to work! 
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Beautiful. I donāt know if Iāve said this before, but your designs are quite nice. I especially love the illustrations on the filter.
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That would be useful! Any ideas where to put that extra knob? With 6 knobs + 1 encoder it is already quite crowdedā¦ With some effort it might be possible to move the display to the right and have the octave knob left of it and the switch for the preset tune pot below it?
Mine works now! As soon as you use the right resistors (I was off by a factor of 1000 
) and donāt mix up gnd and signal on the jacks it all works beautifully!
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I tried to compile the software myself, but it is not working so farā¦ I wanted to test the Renaissaince Firmware and incorporate the changes made for the 12 bit DAC that the THT braids is using. But when I upload the compiled hex file I only see the āCSAWā mode on the display and turning the encoder does nothing at all.
I did test with the original firmware then (with and without the changes for the 12 bit dac) but it is the same with that: the encoder is not working (still need to check if I get sound outputā¦). I asked Nicolas from soundforce (he did the THT braids) but he said he used the original firmware in the same version and his did work.
Any ideas what I did wrong? My module works with the precompiled hexfile from soundforce, but no version of the software worksā¦
I use the mutable instruments development environment (vagrant) and then upload the resulting hex file with STM32 cube.
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Okai, I got the firmware sorted!
The issue was that Nicolas needed to change the pins for the encoder and hence the original firmware does not work (it also needs an adjustment for the DAC)! We got this sorted and he updated the website. If anyone wants I can send around the hexfile with the working Renaissance firmware!
Now I might think about my own modifications of the firmware, but there is a lot of other interesting stuff I want to build xD
Anyway, I got 3 sets of pcbs with panel that I wonāt need and I also got the 2 missing bluepills from aliexpress, so I can give those away if anyone wants to try!
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Iām definitely interested. Are you putting them up for sale someplace?
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Just send me a private message. I noticed that shipping to the US is quite expensive (18ā¬, for uninsured/untracked, ~50ā¬ with tracking), so itās probably better then if I just give you the files, if you are not in Europe (I am in Germany). I will make the files available in any case but it will take some days for me to finish some improvements 
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I finally managed to put this into a Github repo:
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Now that is cool.
M.I. suggest to not call derivatives with the the original name
On https://github.com/pichenettes/eurorack
āāāWe do not recommend you to keep the original name of the Mutable Instruments module for your derivative works.ā""
Letās find a cool name for a cool moduleā¦
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Will you be putting the schematic files in the repo? I realize thereās a PDF at http://sound-force.nl/?page_id=3179 but I donāt see any source files.
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