Grbl_ESP32 Development Board Version 3.1

This is a quick blog post to document version 3.1. This is for sale at Tindie, but you can make your own via these files.

What is new

  • Integrated SD card socket: This no longer uses a plug in module.
  • Integrated 5V 3A DC power supply.: The previous plug in module used the same parts, but was adjustable. The adjustment was very sensitive and prone to drifting a little.

Source Files


This list does not include generic resistors and caps or header connectors.

C1,C6,C11CAP ALUM 47UF 20% 35VNichicon UWX1V470MCL1GB
D1Schottky DiodeVishay SS24 DO-214
J11DC Barrel ConnectorCUI Inc PJ-102A
J20Micro SD SocketKorean Hroparts TF-01A
L1 Inductors 4.7uH ±20% 5.5AnMHCI06030-4R7M-R8
U5Step Down ConverterMPS MP1584EN
U1ControllerESP32 Dev Module


Get it at Tindie

If you want to be notified of future blog posts, please subscribe.


Share and Enjoy:
  • Print
  • Digg
  • StumbleUpon
  • Facebook
  • Yahoo! Buzz
  • Twitter
  • Google Bookmarks

10 Responses to “Grbl_ESP32 Development Board Version 3.1”

  1. Anderson

    Hi, I will use this circuit but Iwould like to change some pins. Is it possible? I know that there are some pins reserved to use special functions.

  2. bdring

    Yes, it is very easy. There is a cpu_map.h file where you assign the pins to the functions. Search Google for a ESP32 Dev Kit Pinout.

    Do not use GPIO6-GPIO11 they are used for on board flash
    Do not use GPIO1-GPIO2 they qare used for the USB/Serial
    Avoid GPIO0 it is used to trigger boot mode.

  3. Ignasi


    I’m trying to build a “self” working station, without a need to connect it to a computer to run again and again a simple gcode.

    I bought your pcb, and got the program working without a single problem, but always connected to Gcode Sender.

    Is there any way I can call the gcode from sd card when sending a high signal or low signal on the “Start” pin?


  4. Ignasi

    I’m trying to build a “self” working machine that runs once again the same gcode when I press a button.

    I got your pcb to work using a universal GCODE sender but I would like to get rid of that computer, how could I call a gcode that’s on the SD card without the need of a computer, just by pressing the “start” button?


  5. bdring

    Could you please ask this as an issue on the github repo. The discussion will probably benefit more people that way


  6. Joe

    Hi, can this provide pwm signal suitable for k40 laser? I saw the 2.5d version but I would like to have a z axis stepper to raise and lower the bed.

  7. bdring

    It can control a laser, but the PWM output is only 3.3v. You should use a level shifter to take that up to 5v.

  8. Doug

    just picked up a used 3040T CNC and will be wiring up Grbl_ESP32. Has anyone blogged this that you know of? I probably can’t put it into the existing metal box but maybe will 3D print a case and move switches and E-Stop to it.

  9. Doug

    Bart, I was about to update my 3040T running your ESP32-CNC board but found an Arduino Nano running grbl directly driving the stock driver board via the DB25. This means no access to the inside of the 3040T controller box!

    While I love your board layout I’m thinking of foregoing the driver boards and jumpering to a DB25 as was done with an Arduino Nano and a Uno. I’m not afraid of getting into the box as I currently have it in pieces since I found the spindle control wire broken at the PS connector and the speed POT is intermittent. I just like the idea of not having people open their 3040 machines, being able to plug a device(esp32 running grbl-esp32) and a USB cable or wireless.

    Have you done this or have any input as I start?

  10. bdring

    That sounds like an interesting project. You would need to know the pinout of the D connector. You would also need to know if there are any optoisolators, etc that might need to driven with a specific voltage or current.

    If you are interested in chatting about this and posting pictures, etc, I go do that via Slack. I will send you an invite.