I can never remember what features the old vi has vs vim. But vim has undo, at least. u and ctrl+r for redo in normal mode.
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Wow, vi. That takes me waaaay back to my UNIX Terminal days.
@conrad404 thanks for the overview!
@diff-arch sorry about hijacking you thread. 
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Donāt worry about it!
Do you guys think it would be fine to also power a LED strip (~10-15 LEDs) with the 24V power supply of the control board, or should I get another power supply. Seems a bit wastful, however I need to get a 24V to 12V converter.
I want to glue the LED strip under the contraption that holds the drag chain for the z-axis cables to light up the workarea.
Unless the LED strip is able to handle the 24v input, no. Only supply it what it is designed to operate at, with the proper amount of current available.
10-15 LEDs is only going to draw a handful of mA from a 12V supply, I canāt see it being a real problem.
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@Cobalt I specifically mention that I need to get a 24V to 12V converter! 
@SupraGuy Thank, I guess the same goes for my 24V power supply.
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For the 24V supply, those LEDs will be really bright for about 3/100 secā¦
You can however put 2 strips in series. I did this on my 3D printer, but the strips I used were kind of crappy and became dim over time. After a couple of years, I just ripped them out because they werenāt helping at all.
Most of these strips can be cut, so you could cut the strip in half (Iād balance the number of LEDs, to balance the resistance load) and wire the (-) terminal on one strip to the (+) terminal on the other. then the remaining (+) and (-) terminals to your 24V supply. With balanced loads each strip will āseeā 12V which itās designed for, and it works reasonably well.
If youāre a little paranoid about it, put a 1/4W 50 ohm resistor on both (-) terminals, and it will greatly increase the lifespan of the LED strips. Edit: To be clear: thatās 2 resistors, one for each strip. Donāt link the 2 (-) terminals with a resistor.
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Havenāt had my caffeine yet 
Do you have the specs for the 24V power supply (how much current it can output) and the voltage/current draw for the LED strip? There are a lot of variables with powering things.
Seems like a good idea! So wiring things in series cuts the voltage in half? Thanks.
No worries!
Itās a 24V 15A switching power supply. I will probably not use more than 1m of the LED strip (probably less), which means 40 individual LEDs. The entire strip (120 LEDs, 3m) uses 7.5W of power (if I interpreted that right).
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Sort of. It wonāt work if the loads arenāt equal. Itās called a voltage divider network, but the short version is that if you put 2 equal loads in series, each one āseesā 1/2 the voltage. If you put unequal loads, you will get an unequal voltage.
In things like our stepper motors, we have a constant current driver. We donāt actually need more than about 3-4V per motor to get our set current. Iād actually think that since we usually have them set to about half their rated current, it might be more like 2-3V per motor, and the drivers supply whatever voltage they need to ā up to the supply voltage ā in order to get the regulated current flow.
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Your best bet would be to do two strips in series like Dan mentioned. As long as both strips are the same length youāll be fine.
Youāre close, or at least the way you described it is close.
Because the coils in the motors are, well, coils, they are inductive loads as opposed to purely resistive loads like resistors. Voltage and current donāt act the same way in an inductor as they do in a resistor.
Basically the voltage levels increase well before the current draw does. If you apply 12V to a stepper motor coil, the 12V will nearly instantly be measurable across the coil, but the current draw slowly ramps up. However, the peak voltage level determines how quickly the current raises. 24 volts will have a faster current increase than 12 volts.
This is where the stepper motor driver comes into play. It monitors the current flowing to the motor, and wants to get the current to a specific level as quickly as possible. To do this, the driver opens the gates and the voltage jumps through the coil while the current follows and rapidly increases. Once the driver notices the current where it wants it to be, it drops the voltage to maintain the current. The power ratings on our motors - lets say 1500mA at 3V - is the saturated power level for the coils. That means that the coils are āfullā of electrons and the current levels wonāt increase.
That is why higher voltage for drivers allow you to move more quickly. Higher voltage makes the current rise faster, completing the current motor āstepā.
Another thing that makes the coils unique is that we measure the coils in inductance and not resistance. That is because while resistance is based on DC current, inductance is based on AC current. When we are sending quick pulses of voltage and current to the motors, we are generating AC currents in the coils. Because of the whole voltage-first-current-second thing, the level of resistance changes based on the frequency of the AC current going through them. So the faster and slower that you send step pulses to the motor, the higher or lower the inductance will be.
So to summarize, yes, LED strips are fun and I want a photo of them!
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Learned something new! Thank you. Iām currently not too knowledgable about electric circuits and such. I only understand the very basics, maybe.
Wow, thanks for explaining all of this!
Iāll post some photos of the project, once Iām done. Iām currently painting the torsion box to protect it a little against wear, tear, and seasonal moisture changes in the air. The LED strip is nothing special though. Itās a simple of-the-shelf warm white one that I had laying around. Itās no neopixel or dotstar strip with addressable LEDs.
@SupraGuy & @Cobalt Thank you very much guys for sharing all that knowledge! I appreciate it.
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@SupraGuy & @Cobalt Do you think 24V 15A power supply is too strong A-wise for the SKR Pro? I saw that the power supply shipped by V1 Engineering is 12V 6A. A 24V 3A one should thus suffise, but mine is rated 15A!
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Not at all. The rated current is what the power supply can potentiality put out. The electronics will pull the current they require, no more.
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Thanks @Cobalt. I wasnāt sure about that, and I didnāt want to immediately fry the SKR Pro when it will probably arrive at the end of next week. 
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No worries! Electronics can be confusing sometimes, and its best to be sure about something before you potentially fry it. Trust me, Iāve been there far too many times.
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