I wish people would put solderable USB pins. Vs surface mount. Then install what ever gender you want with 4 simple solder points
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Pics and explain?
You mean leave solder pads for the USB connections and then solder a connector to them via wires?
Yes. Vcc and ground are easy to reach. It’s the send/receive that are a bitch to solder to.
I do it often, but hate pitches that close.
Looks like the prototype PCB order for the 0.5 HW is gonna be postponed a bit. I’ll look for other PCB houses just in case…
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@SimosMCmuffin - I must have been living under a rock since September. Just seeing this thread now. This looks awesome! I can’t wait for you to finish your next run of boards. Following this thread for the public release.
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subscribed
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how dose the BMS talk to the VESC is it sending some over/undervoltage signal of p groups to the vesc over canbus?
Eg
10S pack at
1s 3.5V, 2s 3.5V, 3s 3.5V, 4s 3.5V, 5s 2.5V, 6s 3.5V, 7s 3.5V, 8s 3.5V, 9s 3.5V, 10s 3.5V totalling 34V which the VESC thinks is fine. would the BMS tell the vesc to act as tho it was 25v Input (due to p group5)?
It doesn’t talk to VESC. Today’s VESC firmware doesn’t care about BMS. It just reads the battery voltage directly from the battery pack.
We have the CAN communication implemented for FlexiBMS though. You can have the BMS connected to VESC via a CAN and then what VESC can do is that it forwards the BMS data to another device such as Metr or my davega. The VESC itself doesn’t process the BMS data though.
The same is true for DieBieMS.
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So no way to ask the vesc to throttle back from under/over voltage of soft or hard battry settings like what you can do with the vesc input voltages.
In my mined I presume both the hardware would be capable of this just a software thing that could be implemented.
To me I think that would be the best of both charge only BMS and Discharge BMS. Because of the safety of protection from overdischares of p groups with out applying the dangers of power cuts throwing you off the board.
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@Trampa is there anything in the works for BMS integration with VESC? Would be pretty damn awesome to have this little smart BMS talking to VESC and allowing VESC to take action if anything is out of shape.
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Not at the moment. Is a matter of implementing that in the VESC FW though.
Note that under normal circumstances your cells don’t get out of balance during a single discharge cycle so doing the cut-off based on the total pack voltage is good enough.
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Yeah but cells can die during a normal discharge cycle. Or connections can break… or shorts can happen… or probably many other things 
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Will the cut-off save the day in that case though? How do things get worse if you keep riding until the total pack voltage is below the cut-off threshold?
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The VESC has voltage Battery Voltage Cutoff Start And Battery Voltage Cutoff End. No way of uterlising them triggered and procedures thro a trigger down the Candus by definable values of p groups in the BMS was my sergestion?
https://www.vesc-project.com/node/1580
A limp mode seems like a happy medium.
Cut further accel, allow brakes.
Triggered via CAN signal
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no idea. I just like the idea of the tiny flexi being able to have the functionality of a full sized discharge BMS.
And VESC integration seems to be the easiest way to achieve that.
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This is the bane of every evolve owner I have triggered this so many times.
I believe the main added value in the charge/discharge BMS (compared to charge-only) is that you get the short circuit protection. You obviously can’t emulate that in software.
I’m not sure if there’s added value in the potential to disable discharge in case something is wrong with the battery pack. (1) If a P-group dies, well, it’s dead. You won’t save it if you stop riding. (2) If there’s short in the pack, that will either kill the whole pack, at which point it will take care of the cut-off by itself… or it will kill just one or more P-groups and we’re back to point (1).
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