Fun fact: there is a way to measure rough current consumption on your Ksoloti Core, including connected MIDI devices etc., using only a multimeter.
Rcs1, Rcs2 and Rcs3 are “current sensing resistors”, “R current sense”.
In short, by measuring the voltage across it using a decent multimeter you can get a rough number how much current that part of the circuit draws. Check with the schematic which Rcs measures which part:
Rcs1 measures how much current is drawn from the PROG USB port. In other words, how much power Ksoloti draws overall if powered via USB.
Rcs2 measures how much current is going out to the HOST USB port. In other words, how much power a connected MIDI controller draws.
Rcs3 measures how much current comes in/goes out the power/MIDI header, J8 (in case you’re powering your Core from an external 5V supply, or power external stuff from here).
That’s all nice and geeky and all, but how do I even measure this?
I am glad you ask. With the multimeter in DC voltage mode, You carefully place the probes across the two pads of the Rcs resistor. You’re measuring a tiny voltage drop as current passes through this resistor.
Go slow so that your probes don’t slip off the pads and slide somewhere where they could cause a short! Not likely but still, better safe than sorry.
Image: Measuring voltage drop across Rcs1 to know how much current Ksoloti draws from the USB PROG port.
Rcs1, 2, 3 are all 50 mOhms. Applying Ohm’s law, you divide your measured voltage (usually around a few milliVolts, so your multimeter needs to have that sort of resolution) by 0.050 Ohm.
Example:
0.004V / 0.050 Ohm = 0.08A
So around 80 mA. Granted, the resolution is 20 mA at best, and only if your multimeter can handle such low voltages, but it may still help you debug things at some point!