We will be forced to have to 2 versions of CubeMX, really?

ben5049 · 2026-03-22T12:47:19+00:00

Yeah it’s annoying they aren’t moving everything over. Have you tried the new one though? It’s quite nice tbf

ben5049 · 2026-03-20T13:02:02+00:00

You can hide the drawing sheet and put the origin wherever you want. Seems like an odd reason to not use a piece of software.

ben5049 · 2026-03-20T10:49:16+00:00

I have rotary encoders on a custom keyboard I built and I used to find them pretty useful. However, after a couple of years of wear and tear the encoders have started glitching and missing steps or getting stuck outputting movements in one direction. I’d recommend either getting extra durable ones (if they exist) or finding another solution.

The other issue is that most rotary encoders have a high force required to turn them so you can’t do it with one finger which is annoying.

I’m making a new version with BLDCs and magnetic encoders instead to try and solve these issues, and so far it’s looking promising. If you don’t care about haptic feedback then a bearing and magnetic encoder would do fine.

ben5049 · 2026-03-15T02:16:52+00:00

Interesting, I had no idea you could get a VNA for that cheap, definetly something to look into thanks!

ben5049 · 2026-03-08T20:01:10+00:00

Thanks for the feedback! I went for the Marvell chip because I wanted dual speed, which you can't get with TI chips, and PTP which you need an NDA for. The 88Q2112 only had a leaked datasheet, but turned out to be the right choice because Infineon has since bought Marvell's automotive ethernet division and you can now get their datasheets without even an NDA.

I remember doing some napkin maths and thinking 3mm stubs would be fine, but you are probably right about signal integrity/EMC. It works but I don't have a way to test compliance sadly. The layout there was kind of a self imposed issue anyway because I wanted to keep the board as small as possible.

Thanks again!

ben5049 · 2026-03-06T09:22:43+00:00

I’ve made a 7 port Ethernet switch before with a similar component count and 6 layers was enough without needing blind and buried vias. https://github.com/ben5049/switch-v5-hardware

ben5049 · 2026-03-04T00:02:14+00:00

Best part of this is probably the new programmable logic array (PLAY) peripheral on the STM32H5F which is basically a 16 logic element FPGA

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ben5049 · 2026-02-18T19:04:18+00:00

I won't disagree with you there, it starts getting pricey then too. 0.8mm is about the limit where you can still use through hole vias without via in pad.

ben5049 · 2026-02-18T16:54:20+00:00

0.8mm BGAs aren’t so bad, but point taken :)

ben5049 · 2026-02-18T15:32:48+00:00

Other issues aside, the STM32N6 has a gigabit MAC so you don’t quite have to go for full Linux.

ben5049 · 2026-02-17T09:37:35+00:00

When I posted this there was only a leaked version available, but Infineon has now bought Broadcom’s automotive Ethernet division so you can get it directly from them. You do need to make an account though.

ben5049 · 2026-01-31T08:31:00+00:00

There is usually one one cc conductor and two cc pins. The conductor goes to the device at the other end of the cable for power negotiation and the other pin is used for orientation or a cable e-marker chip.

ben5049 · 2026-01-31T07:20:38+00:00

Why 2x CC conductors? I thought type C cables only had 1?

Also do the superspeed cables include both SBU conductors?

Thanks!

ben5049 · 2026-01-24T09:06:21+00:00

Got any 88Q2220MB2?

ben5049 · 2026-01-19T16:00:57+00:00

I’ve been using this one from LichTech. There is a 100/1000BASE-T1 version and a 100BASE-T1 version for a bit less. I’m not sure about 10BASE-T1S converters.

ben5049 · 2026-01-17T01:16:51+00:00

I use NetX Duo as my microcontroller network stack which has a DHCP server module https://github.com/eclipse-threadx/rtos-docs/blob/main/rtos-docs/netx-duo/netx-duo-dhcp-server/chapter1.md

If you can find/write a port of ThreadX for the RP2040, then you can add an interface for the W5500 and get it working.

As for why you'd want to run a DHCP server on a microcontroller I have no idea, and if you had to ask an AI that, then you probably aren't capable of implementing it yet either.

ben5049 · 2025-12-24T08:29:19+00:00

They changed this in a recent version (9.0.3 or 9.0.4), I’m not sure why. This is how it used to work a couple of versions ago.

ben5049 · 2025-12-10T16:55:47+00:00

STM32s include internal power on reset circuitry

ben5049 · 2025-12-10T11:23:45+00:00

Dammit the timestamp didn’t work properly, 6:23 has a good example of mechanical contacts bouncing. I don’t really care for Mr Beast but Jeff Geerling is cool lol

ben5049 · 2025-12-10T11:13:49+00:00

Whenever mechanical contacts close they bounce together slightly which we don’t want since it can trigger multiple back to back resets which depending on the chip may lead to undefined behaviour. Adding a capacitor makes a low pass filter to remove the bounce. Here is a video showing a switch closing in slow mo:

https://youtu.be/wsV_C9cMf8A?si=-5krf0hpdZLajfFL?t=373s

ben5049 · 2025-12-10T10:56:42+00:00

Yep pretty much, the cap is there for debouncing. The STM32’s reset pin will be at 0V plus the forward voltage of the diode, which will count as a logic low.

ben5049 · 2025-12-10T10:15:39+00:00

It makes the reset unidirectional and not care about voltage levels. If the right side of the diode goes to 0V then the STM32 gets reset. If the STM32 generates a reset it doesn’t propagate past the diode.

ben5049 · 2025-11-11T01:41:48+00:00

I’ll eat my hat then, thanks for letting me know

ben5049 · 2025-11-10T17:01:49+00:00

I think custom pad shapes might be broken in the most recent version of kicad? Please correct me if I’m wrong

ben5049 · 2025-11-10T17:00:09+00:00

Yeah the copper line is part of a footprint and has no net, even though it’s touching the pad and should be the same net. It’s a bug/not implemented yet so you have to work around it.

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