ESP32/S2/S3 LinuxCNC Controller (6 axis hardware step gen), USB plug-and-play

Actually starting with the Mesa sources, modifying the pin mapping, defining the modules you want and then building the firmware I’ve found to be far easier than any other platform, be it STM, esp32 or anything else. I will give that the Mesa code base is also more mature.
I have looked into the various projects around, added a few bits of code here and there.

I reckon if you set up a build environment for the Spartan 6 family and had a go at building a bog standard project for a Mesa card you’d see how insanely easy it is.

Like I said before the biggest letdown in some of these projects is the electrical interface from the motion controller to the machine. A robust yet simple design for getting the logic levels of the main micro controller to 12/24 volts of machine controls is needed. I would also suggest, going against modern trends, is to stick to through hole components where possible, for ease of assembly. Even tho I have years of experience in smd soldering I still tend to stick to through hole for ease of soldering and obtaining the parts from my local electronics shops. I suppose living Down Under affects this as well as either we have to wait at least 10 days for delivery, even tho Element 14 and RS have local warehouses, or spend a decent amount at Digikey or the like.
It’s sounds like Tommy may have similar experiences in his neck of the woods.

All in all its great seeing what others are doing.

Another suggestion for you Wizards of Code, getting a simple code base for Smart Serial on one of the more popular controllers would be fantastic. I’ve looked at the STMBL code but it goes over my head then out in one ear and out the other.

• ESP32-S2 (Single Core!)
• USB Networking (No Ethernet)
• Waveshare Pico S2 module
• Raspberry PI 4
• 4 Axis
• High speed test

Impressive. Be mindful that we've received an email last week about the delivery of pre-sale ESP32-P4. We should get our hands on that badboy anytime in march. No specifics about the global rollout of the device however expect this to be a month or two after the engineering samples are out.

If you are serious about maintaining a community espressif solution for Linuxcnc, I would put your project on hold until then. P4 brings quite a bit of hardware parallel IO capabilities and packs a significant punch if compared to the S2 or dual-core S3.

All in all fascinating and looking promising judging from your video, thanks for sharing.

With the USB interface can you still do threading and other ops that need spindle sync ?

Thanks Mecanix. Yeah I'm all over the P4 Thanks for the heads up though! Its certainly going to be interesting to see how they perform and any quirks.

I intend on having firmware releases for ESP32 SPI & RMII Ethernet, S2 USB, S3 USB and P4 USB & Ethernet (since it has once again). The P4 won't have ESP-NOW low latency wireless though which I believe people may like to adopt once they see how useful it can be.

cornholio,
Yes that is a feature that will be added soon. I've chosen a design path to ensure PCNT counter peripheral is available for full use so high speed encoders etc can be implemented. It's an issue in my github repo.

I'm also aware of the hesitancy towards USB for EMI on CNC machines however it's still a diff pair like Ethernet, shielded USB cables (so many crap ones) and ferrites should ensure no issues. The USB PHY on the S2/S3 is very robust I've found so at least based on what I know and experienced I doubt it would be an issue for most use-cases

Are you bare metal techdoc programming this or using the idf SDK apis?

Also looking forward this P4 hardware. If you plan on making use of the hardware counter this is where the P4 will shine. E.g. the existing S3 won't multi channel the hw counter, to my limited knowledge mind you.

Are you working from a repo? Can we spy on your progress?