New grbl cnc controller from Bart Dring

I forgot about the tmc drivers. That is pretty neat.

I have one coming. Hope it is here tomorrow. Why i got it was i am hoping to use it with Easel.

Shoot I thought it was missing a feature…squaring …turns out it is not.

Maybe that is the better option…

Danggit, I have the right USB but wrong pin out. Gotta get the full kit.

Regular GRBL gcode gives more software options with less fussiness also

I was unsure about the auto squaring. If you look at the endstop logic, it uses one pin on the esp to do both endstops. I can imagine a solution like bringing both motors in until it trips, back off bot motors until it clears, then bring each motor in one at a time until they trip individually. But I have no idea how it’s actually done. I haven’t ever had endstops on my LR

.Bart has put up a wiki page on auto squaring https://github.com/bdring/Grbl_Esp32/wiki/Motor-Ganging-and-Axis-Squaring

Well, there you go:

It uses a 3 step homing process to square. It first moves both motors towards the switches until either switch is contacted. since the switches are on the same input Grbl_ESP32 cannot know which side touched. It now homes each side separately. This puts minimal stress on the gantry because each side only has to move a tiny bit independently at this point. It will know what side touches this time because it knows what motor is moving.

I am guessing I read this and then forgot about it.

Auto squaring works vey well. I had a noise issue that I fixed by separating the endstop cable from the stepper cable. After that it works perfectly.

I have several nodemcu’s and esp8266 lying around so I’m aware of the differences.

Well in that case you will know that neither of those will work as you need a ESP32s DevModule with the correct pinouts, there will be many who will be unaware that there are different modules out there all with the same name but with different pinouts.

Actually there are nodemcu’s that use the ESP32 parts and modules with the correct pinout may be branded nodemcu. However you are correct in pointing out that not every ESP32 module will work. The board manager in Arduino lists lots of ESP32 modules and options and it’s important to find the right match. Frankly that is a bit of a mess but Bart’s grbl port works well with the right module. The documentation is also in good shape.

I am using Bart’s MPCNC board on my LR2 with end stops and auto squaring. The sequence for squaring is like you described.

I plan to his new board with the RS485 module to control my new spindle. Then I will use the old board on a Primo.

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I got mine from here Its the yellow pin version that has the correct pinout

Ok, just got a couple of ESP32 DevKit 32U boards and antennas. I figure having a little more range would be good…

A bit of a pain, though. I configured the firmware for my WiFi, but it kept coming up in AP mode. Finally just copied index.HTML.gz to my phone and connected to it, then reconfigured it from the ESP3D interface.

Sitting with the MPCNC board in my Tindie cart. Still want @buildlog to release the six pack… May end up with two ESP control options… :grin:

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Yeah, pulled the trigger on that one. Already have the DRV8825s…

Dope! hope it’s in my budget range!

From what I recall in his comments, he’s hoping for ~$40USD for the board, and ~$10-$30USD for the I/O cards, depending on their function. My SWAG is that you can use it standalone for ~$40, add the 4x switch input for $10-$15 for dual endstops, $10-15 for a relay board to turn on and off your spindle (or maybe an RF485 or 0-10V to communicate with it), and $20 for the 4x5V output to handle all your fan and laser needs.

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@vicious1

Did you ever try out that 6 pack? I am strongly considering getting one for my primo build.

Well sort of I have it on my office build, did some drawings and tested the dual homing out a bit. I was waiting to hear back from him before I get too deep into it.

My opinion thus far is that it is very worth the money and seems to be fairly future proof as well. As quantities rise he dropped the prices so that is a good sign.

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