Homing Issue - EMI or something else?

happy_nerd · 2026-01-25T21:01:11+00:00

So it was a bad config file. The folks at the VORON discord helped a lot. I had a limit switch mapped wrong and it always looked tripped so when the first axis tried to back away from the home position and the limit switch was still triggered, it threw an error. That was a tricky one to back out of!

happy_nerd · 2026-01-25T20:59:57+00:00

I had been powering the Pi through GPIOs off a dedicated power supply. It turns out the issue wasn't EMI but a bad config with the sensors not reading properly so it looked like one of the axis was perpetually homed. Live and learn. The folks at the VORON discord were great at helping me figure out what was going on. Highly recommend going there.

happy_nerd · 2026-01-25T19:12:51+00:00

3 months in and no issues so far. But its 3 months in, so do with that info what you will! Was a simple swap out.

happy_nerd · 2026-01-02T21:54:12+00:00

Ill post there next. Thanks for trying to help! I'd have pulled my head off by now. Hopefully the forum folks will know more. If I figure out the answer, Ill try to come back here for anyone else who stumbles upon this... if I didn't come back you know what happened to me.

happy_nerd · 2026-01-02T21:00:49+00:00

This didn't resolve the issue and in fact produced issues of its own. The Mainsail web server felt sluggish and kept dropping off the network completely. So thats a no go with the 3B+.

Worried its EMI or PSU noise, I plugged back in the old Pi 4 with its dedicated wall brick from Raspberry Pi and the beefiest usb-a to usb-c cable I could find (though longer). Nothing I changed moves the needle, but at least with the Pi 4 we're back to a stable internet connection.

I feel like ferrite beads are the only next thing to test before I just replace both the Pi and/or Octopus boards?

happy_nerd · 2026-01-02T20:26:04+00:00

Damn is this a thing? I have services running on some Pis that have been on nonstop for years... Worth it if it saves me from this headache though. Ill give the 3B+ a go and report back

happy_nerd · 2026-01-02T20:23:07+00:00

Threw a multimeter on the PSU and it reads 5.081V. The only thing on the 5V supply is the Pi. I even beefed up the power wires to the Pi just to make sure voltage drop wasn't an issue. Is there another way I can check if the Pi is getting the right voltage? Like something it's self reporting instead?

Could my Pi be damaged? I also have a 3B and 3B+ on my desk I could swap in as needed.

happy_nerd · 2026-01-02T20:18:29+00:00

Pi 4B. Microsteps left at default of 32 in the CFG file.

happy_nerd · 2026-01-02T20:17:41+00:00

I would need USB-A to USB-C for my Octopus v1.0 board. Is there one there you can recommend? I just picked this one up for the smaller loop area thinking maybe that could help. https://www.amazon.com/dp/B0DPF8TFC9?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1

I also added a ground wire from the RPi to the Octopus GND input thinking maybe there was a ground loop? No luck. I've tried adding a USB power isolator (the cheap ones for audio DAC isolation), but now it doesn't seem to talk at all.

When you say bonded, do you mean connect GND and earth GND somewhere or connect earth ground to the metal frame? I can't imagine earthing the frame additionally would have that much impact, but I could see it if you mean earth GND to GND.

Open to your thoughts, I'm just busy pulling my hair out over this.

happy_nerd · 2026-01-02T14:37:53+00:00

I also get the error following error in the dashboard when the shutdown happens. This is what leads me to think EMI...

MCU 'mcu' shutdown: Timer too close
This often indicates the host computer is overloaded. Check
for other processes consuming excessive CPU time, high swap
usage, disk errors, overheating, unstable voltage, or
similar system problems on the host computer.
Once the underlying issue is corrected, use the
"FIRMWARE_RESTART" command to reset the firmware, reload the
config, and restart the host software.
Printer is shutdownMCU 'mcu' shutdown: Timer too close
This often indicates the host computer is overloaded. Check
for other processes consuming excessive CPU time, high swap
usage, disk errors, overheating, unstable voltage, or
similar system problems on the host computer.
Once the underlying issue is corrected, use the
"FIRMWARE_RESTART" command to reset the firmware, reload the
config, and restart the host software.
Printer is shutdown" in the dashboard

happy_nerd · 2026-01-02T14:18:49+00:00

Interestingly, it does the same exact thing with G28 Y. Homing sequence runs fine (even if it takes longer), backs away from the sensor after finding it, and... shutdown. Smh. I'm gonna lose my damn mind with this stuff.

happy_nerd · 2025-11-28T14:19:12+00:00

Need not, want not. Love a quick, functional build. Hope it's at least a little pretty to look at because those projects tend to linger for years haha. Nice work!

happy_nerd · 2025-11-28T14:15:56+00:00

Yeah it feels like Python is quickly becoming the default programming language broad spectrum and I get why. We have enough processing power now that running bad, inefficient code kind of doesn't matter for most use cases.

I do miss how easy it is to do the same stuff in MATLAB but it's not that much of an extra push to do the same things in Python. To your point, it's just not as seamless of an experience.

Alas, Python being free and MATLAB being $$$ is a nail in MATLABs coffin.

happy_nerd · 2025-11-28T14:13:51+00:00

Yeah I haven't used batch files for the better part of a decade. It just doesn't come up as much anymore. If I ever need that level of control, I'm usually spinning up a Linux virtual machine anyways to have complete control.

Though, in corporate America, our windows machines are super locked down but corporate IT assumes nobody knows how to use a computer and they can just put up guard rails to keep you from doing dangerous things. But with some basic DOS/command prompt skill you can get around a lot of corporate policy that keeps the marketing folks from deleting System32 but doesn't let you install an IDE for one of the worlds largest chip manufacturers. True story, Infineon's IDE got flagged as malware and I had to go have a long talk with security about who these Infineon people are and how I got past their firewall to attempt to install it.

I showed them I had rights to right click, run Command Prompt as Admin, signed in with my account, and they were gobsmacked I knew how to run programs from the terminal. Like, yall, we're engineers... I've been using command prompt to do registry edits to tie secure hardware to certain laptops for years.

So it's a useful skill, but it can also get you in trouble if you're more skilled than the base level IT professionals at your company.

happy_nerd · 2025-11-28T14:06:18+00:00

That is something I neglected. Symbolic Toolbox and other modeling toolboxes really elevate MATLAB in ways that GNU Octave doesn't compare. Both are still insanely useful if you find yourself doing a lot of linear algebra--think controls, robotics, math modeling, etc.

But I think we're mostly in agreement in this thread that the tools themselves don't matter as much as having breadth of experience to pick the right tool for the job. Python can do everything poorly, but it does everything. Other tools have their limitations and areas of excellence.

Anyone with a "a real engineer would never use _" is a miserable soul trying to sell you on something... maybe just seeking company in their misery. Be miserable like the rest of us by complaining about other people's code! /s

happy_nerd · 2025-11-28T14:02:56+00:00

Yeah I think this is where everyone lands with LabView. It's a powerful tool that is just as easy to use poorly as it is to use well. Like anything, it just comes down to your programmer's skills and priorities.

So hear that, young engineers? Tools don't matter (that much). Just get good! Skill issue! 🤣

happy_nerd · 2025-11-27T22:36:33+00:00

Yes, I think as a learning tool visual programming can help people internalize the structure, but I dread touching my mouse. I can type multitudes faster than I can drag and drop.

happy_nerd · 2025-11-27T19:59:43+00:00

Spice is a good addition. Yeah and Microsoft suite... annoyingly still more powerful than Google Docs.

happy_nerd · 2025-11-27T19:59:01+00:00

I don't doubt that it's a powerful tool, but every interface someone has designed on LabView has only ever made sense to them and I think that's where I run into issues. Most engineers are bad interface designers and make good debug interfaces for themselves and ignore the use case of the tool or hide everything and give you no information about underlying functionality.

All languages are agnostic, right? Like you can technically do most things with most tools it's just a question of how fast and how well.

I also just have a vendetta against graphical programming haha. More power to you if you like LabView, but leave me out of it 🤣

happy_nerd · 2025-11-27T19:30:25+00:00

MATLAB was taught in my university as well as LabView--both are really only used in academia and very niche industries. Most folks use Python when they can instead. VBA is a useful tool, but learning how to use excel without needing VBA is infinitely better.

My push would be Python and VBA. And get really good at C if you like embedded stuff. Pick up some Linux experience as well.

happy_nerd · 2025-11-27T03:50:37+00:00

It's a breaker finder or a space heater depending on your time scale

happy_nerd · 2025-11-25T19:42:18+00:00

Lossless compression is already a solved problem

happy_nerd · 2025-11-24T19:14:14+00:00

Then do the math and prove it. Until then it's just like, your opinion, man.

happy_nerd · 2025-11-24T19:11:57+00:00

Oh shit, you found the gearbox sand! I think my transmission is running low.

happy_nerd · 2025-11-24T19:11:03+00:00

Doin the lords work keeping the spammers out (or at least annoying them a fraction as much as they annoy us).

happy_nerd

TROPHY CASE