F-Of-C - open-source Free-Of-Charge vesc6 board in development. Schematics available

This is looking better and better, great job. Can we get some performance measurements? Maybe with foc_openloop or something similar to what MakerX does on their youtube channel?


Eventually, you will get that :slight_smile:

As of now, I’m a little more focused on the assembly procedure, and what I can do to make it easier.


So here is a little update:

my mosfets are already through customs and in think i will get them this week, I keep you posted.

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Follow this link for the FreeDRIVE JLCPCB ordering guide.


Hi. I’m trying to figure out how to control LED strips like ws2812. Anybody who knows which pins can be used as data pins?

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Anyone in the U.S. interested in doing a group-buy? It seems the pricing is really good at 5 or 10 units; but that’s a lot more than I need.

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The answer is in the video,its written in the code. Either hall sensor or pwm.

If they are used, maybe some of the adc pins on the comm connector, ADC8(PB0), ADC9(PB1) or ADC15(Pc5).

I’m not able to put in the time into being a good public beta tester and give feedback in the near future, but if there’s open spots for a gb, I’d be in for 2 and up to 4 if needed.

(I’ll also be in your area for the next couple weeks to potentially save a couple bucks on shipping if you’re putting in the order soon)

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I sent you a PM to arrange this if you’re up for it.

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As you have probably noticed, I have not yet officially “released” the hardware. I have recently made an order for 10 more boards which I have improved slightly.

(however, I promise not to do any modifications that is not compatible with the current gerbers, because I want to be nice to those who have already placed an order).

I have primarily focused on solving issues regarding the assembly procedure. What I have improved (currently waiting for the arrival of the boards):

  1. Added support for 4-wire on/off momentary switch.

  2. Moved the power module up so it’s “on top” of the gate-drivers, so screw holes for attaching heat sink are accessible always.

  3. Mirrored all components on the PILL, which means that the terminals are axactly the same place if you turn it around bottom-up (and thereby it is still compatible with current gerbers, just needs to be mounted up-side-down). By doing this the “build height” of all the stuff on the back-side of the main module can be much smaller, and the pill can now pass under the heat-sink attached to the mosfets - which has been a huge constraint.

  4. I even think it is possible to attach the pill on back-side with “swiss machine pins” and it can still pass under the heat-sink

  5. I really like the LIGHT feature, so I have made PB6 available as a data pin on the Power jst-connector. The draw-back here is that PB6 also controls the led for “error”, and this “error” pin will do funny stuff when you use LIGHTS. (but who cares?).

This image shows the 4-pin jst for on/off momentary switch attached to the Power Supply.


And why I order so many boards for myself?

No I’m not a billionaire, but we happen to use the vesc for a robotics research project I’m involved in at the place where I work. It’s completely “accidentally” - one in a million. Actually, it’s quite nice. We are controlling multiple vescs (coordinated movements). So multiple velocities/positions are send to one vecs, which then distributes the information to individual drives through CAN.

In my last order at jlcpcb they wrote me a message that “there were 3 designs” (which I personally think is b.s.). I cancelled the order and made another on some hours later, and it went straight through.

Group buys in EU:
I could organize something like this, but I’m a little hesitant, because what if someone complains about stuff - you know, I’m the designer so it’s natural to go to me

But maybe it should be more like a “kit”. You know, you’re going to need pcbs, mosfets, capacitors, potentially mica insulation for heat sinking + screws + insulator washers

I have a 6040 cnc router, so I could potentially produce batches of aluminum heat sinks pretty easily… Or, maybe you can order heat sinks cheap from jlcpcb - they have this new feature where you can order cnc machined stuff.

All this is what I can do theoretically. The big question is, if I have the time for it… For now I want to be absolutely sure that the stuff on the board is working. I’ve got a go-cart-like hub motor at home and I want to build a one-wheel using this. I don’t know yet how the hardware will perform for hub motors. I use low side shunts whereas e.g. the Vesc 75/60 uses phase shunts. Though, I think the Vesc 75/300 also uses low side shunts. So, just so the “one-wheel”-people is aware of this uncertainty.

(for US citizens: Don’t vote for Trump for heavens sake. Don’t be that stupid, ok? The President of the United States is not the President of the United States. Someone with this title more or less decides the politics of the whole western hemisphere, so please don’t force this guy down on all the rest of us… Thanks, in advance)


I guess you can call such “lisp” code from a GUI-popup/App created in QML. So you can call it from the vesc app? Anyone doing this currently in vesc app, or do you have to use “float control”, or?

Good to see you are re-thinking the assembly of the mcu pill. I recently received my PCBs. I succeeded to cut 2 boards, flash the Fw and test the power converter board. Unfortunately I did not succed in installing the MCU pill. After soldering it, I figured there must be a short between 5V and GND, or at least something very low R. I measured 2-3 ohm between 5V and GND on the pins of the main board (without the power converter attached). With my lab PSU on the lowest current limit (200mA), the power converter board survives, but does not like it, no blue light when connected to the main board. No LEDs on the mcu neither. The only way to find the problem is to remove the mcu pill but this is almost imbossible without damage.
I guess I have to try the next fresh PCB…
Swiss machine pin headers would make it a lot easier.
I found it also hard to mount the pins for the jst 2.54 mm pin headers, my pins were allmost too short.


i got the fets delivered last week and guess i will have the time to finish them at the WE.

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Damn… Actually also 1 board that I soldered has a short between 5V and GND after attaching the PILL. I will investigate further…

Regarding JST:
The assembly-guide instructs you to “pull out” the pins of the pin header at those terminals at the positions of the JST pins (like shown on the image). Did you do this?

You’re supposed to use the pins of the standard pin headers as the pins of the JST, which means that you need to completely remove the original pins of the JST: Did you do this?

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I will take a look at the board I have that failed with (maybe) the same 5V to GND short. I managed to desolder the “pill”, so I might be able to find the cause.

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I remember that you ordered with the gerbers where I attached some dummy traces. One of these traces might have been a 5V trace (I don’t remember if there was a dummy 5V trace, but you can see that in the order info of your jlcpcb order, where you can see the traces). If there was a dummy 5V, it would mean that you have sawed through that trace, so make sure the cut is “clean” at this exact spot… Just a thought.

Yes, I followed your guide on Git. I pulled the Pins where the JST sit. They were flush on the pill side, so just „solderable“. On the main board side I tried to solder them with minimum solder. It was difficult and I had to scratch some solder from the pins. I then removed the original pins from the jst sockets and put them on the longer pins that stick out on the mainbord side.
Maibe it would help to use just the pins without the distance holder for the jst pins. This way they coul be soldered from between the boards. That would avoid solder building up below the jst sockets.

Yes, you connected gnd and 5v, I remember the 5V LED of the power bord was lit, when I connected the flashed pill with the solder bridge to the USB.
So I , I though about a short from cutting those traces too, but It looked clean. I checked the second board I cut with a multimeter and there is no short between 5V and gnd.